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Al–Si–Cu–Mg foundry alloys are used in casting process technologies. However, their strength properties remain low due to their microstructural characteristics and porosity. In this work, the microstructural characteristics, dislocation densities, and mechanical properties of Al–Si–Cu–Mg cast alloys prepared through different casting methods were studied experimentally. Four casting processes, namely, gravity casting (GC), rheocasting (RC), thixoforming (Thixo), and Thixo with heat treatment, were used. The GC and RC samples had mainly dendritic α-Al phase microstructures and exhibited coarse Si particles and intermetallic compounds in their interdendritic regions. By contrast, the Thixo and heat-treated Thixo (HT-Thixo) samples exhibited microstructural refinement with uniformly distributed α-Al globules, fine fibrous Si particles, and fragmented intermetallic compounds among α-Al globules. The accumulation of dislocation densities increased in the Thixo sample as the strain was increased due to plastic deformation. Furthermore, the ultimate tensile strength and yield strength of the HT-Thixo sample increased by 87% and 63%, respectively, relative to those of the GC sample. The cleavage fracture displayed by the GC and RC samples led to brittle failure. Meanwhile, the Thixo and HT-Thixo samples presented dimple-based ductile fracture.

Introduction. The problem of combining continuous monitoring of the main informative process parameters (mass, temperature, melt consumption) and control of the pouring process is relevant for almost all filling devices today.Problem Statement. The development of pouring accuracy methods, particularly for small-dose pouring is an important task for the foundry industry.Purpose. The purpose is to study the dependences of the flow characteristics of the magnetodynamic equipment on the supplied voltage in various conditions of its operation.Materials and Methods. Physical modelling has been applied for the study of dosing accuracy for small doses in the range of 1.5—3 kg.Results. The coefficient of the numerical dependence of instantaneous mass flow consumption of a modeling fluid in the trough on the instantaneous mass of a modeling fluid in the trough has been established based on experimental studies with the use of a physical model of magnetodynamic device (MDD). The studies of filling doses within the range from 1.5 to 3 kg have shown that this coefficient corresponds to the range of the electromagnet supply voltage from 12.3 to 16.3 V. There have been determined the efficient range of the poured-metalmass to instantaneous-mass-flow-consumption ratio in the course of casting (2.20—2.25) and the corresponding range of the MDD electromagnet supply voltage to minimize the effect of jet pulsations on the dosing accuracy byreducing their amplitude. The dosing error does not exceed 1.5% by dose weight in the case of pouring small portions (1.5—3 kg).Conclusions. A new technical solution for MDD with an inclined weighting trough of a conventional design has been developed based on the electromagnetic transfer of a force proportional to the instantaneous melt massin the trough. The implementation of this solution makes it possible to reduce the number of strain gauge power sensors for the instantaneous measurement of the melt mass, from four sensors installed under the melting pot of the MDD prototype to one placed directly under the trough.

In this work, they going to use a foundry simulation software to compare the virtual vs real results and try to reduce the time of the real process in the foundry area. In the real process they work with the re-engineering process of the pistons, first they take the original element and take the physical properties (length, width, thicknesses, etc.), after make a cast design and is assigned some parameters for the process, planning the process to make a test, after the casting process it goes to the machining process and finally the final inspection says if all the process during the tests is correct, if not, we need to take others parameters or casting design. With this project is going to be possible to save time in the foundry area and make a virtual process to see the result and change all the necessary things to have a perfect process.

Centrifugal compressor impeller is one of the main parts in supercharger of the diesel engines to increase the engine power. Because the blade profile is complex and its thickness is generally thin as 0.7~2.0mm, it is important to ensure the precision for the enhancement of the quality of product. In order to prevent the formation of shrinkage defects, optimal gating systems were designed to examine the molten metal flow and solidification behavior during the pouring and solidification process. The optimal main parameters of casting process have been verified by experiment, and the rapid casting has been realized based on FDM-processed PolyCastTM pattern and investment casting. As a result, the processing time and costs reduced and casting quality enhanced in the foundry industry.

The features of the use of waste foundry sand to obtain secondary products are presented. The properties of the surface of mineral particles of waste molding sand are described. It is shown that on the surface of the particles there is a porous layer capable of increasing the adhesion forces of mineral particles with bitumen in the production of asphalt concrete. It has been established that the modified surface of the waste foundry sand contains up to 40% carbon, which provides an increase in the adhesion force between the mineral particles of the waste foundry sand and bitumen. It has been experimentally proven that the use of waste foundry sand in the composition of asphalt concrete can improve its physical and mechanical properties.

PurposeThis research establishes a suitable casting model for magnesium alloy wheel. The casting of the wheel is an element that must be considered in the design of the wheel. Casting is an important basic process and technology in the field of machinery which is widely used in production, transportation, national defense, social life and other aspects. Computer numerical simulation of the casting process can shorten the product manufacturing cycle, reduce product costs, reduce casting defects and ensure product quality. The casting material in this study is AZ91 magnesium alloy used for wheel lightweight.Design/methodology/approachLightweight research of automobile is a significant trend, and people are paying attention to the lightweight design of automobiles. Higher requirement was proposed on design and casting performance of the wheel which is an important part of lightweighting vehicle. In order to achieve better quality, the parametric studies of alloy wheel and casting are necessary. This research designs a new model of automobile wheel, to ensure energy efficiency, the wheels must be as lightweight as possible, using magnesium alloy material for lightweight.FindingsAnalysis of casting process is a very complex issue. This research based on finite element theory and actual production, designed reasonable casting model, instant filling and solidification data were obtained. Aiming at reducing casting defects, process improvement of casting riser structure was designed. On the basis of the foundation, it has important guiding significance for actual foundry production.Originality/valueThis research establish a suitable casting model for magnesium alloy wheel. Aiming at reducing casting defects, process improvement of casting riser structure were designed.

Purpose In the construction sector, river sand has turned into a costly material due to various reasons. In the current study, used foundry sand (UFS) and spent garnet sand (SGS) are used as a partial and full replacement to sand in concrete production. Design/methodology/approach The objective of the work is to develop non-conventional concrete by replacing river sand with a combination of UFS (constant 20Wt.% replacement) and SGS at various percentages (20, 40, 60 and 80 Wt.%). Findings Compared to conventional concrete, the 28 days compressive strength of non-conventional concrete (with UFS at 20% and spent garnet sand at 20%, 40% and 60% were 8.12%, 6.77% and 0.83% higher, respectively. The 28 days split tensile strength of non-conventional concrete (UFS at 20% and SGS at 20 and 40%) were 32.2% and 51.6% higher, respectively. Research limitations/implications It can be concluded that 60 Wt.% of river sand can be combined replaced with 20 Wt.% UFS and 40 Wt.% SGS to produce good quality concrete whose properties are on par with conventional concrete. Practical implications The results showed that combined SGS and UFS can be used as a partial replacement of river sand in the manufacturing of concrete that is used in all the applications of construction sector such as buildings, bridges, dams, etc. and non-structural applications such as drainpipes, kerbs, etc. Social implications Disposal of industrial by-product wastes such as SGS and UFS affects the environment. A sincere attempt is made to use the same as partial replacement of river sand. Originality/value Based on the literature study, no work is carried out in replacing the river sand combined with SGS and UFS in concrete.

The article is devoted to the development of a computer simulation model of the realiz-ing gas-dynamic pressure technological process on the melt during self-sealing of a casting. The process of developing a simulation model of this technological process is described on the example of a steel ingot. Considerable attention is paid to the stage of evaluating the parameters of the technol-ogy implementation, which includes mathematical modeling of the steel ingot solidification process, analysis of temperature fields to determine the sealing time and the rate of controlled gas pressure supply during the solidification of the casting. The information model of the gas-dynamic action technological process on the melt in a casting mold for a steel ingot is presented in the form of a table containing a description of the procedure for carrying out this technological process, the content of the stages and their duration. This information model contains the following stages: assessment of technology implementation parameters, pouring melt, gas supply device introduction, casting sealing, supply of regulated gas pressure during the solidification of the casting, pipeline removal.The procedure for the implementation of the developed simulation model in the form of a computer model - a game "Virtual Foundry" application is described. A universal game pipeline is presented, implemented by means of graphical 3D modeling, taking into account the scenario of the player's interaction with the game environment. The interface of the Virtual Foundry graphic simulator, the game scene and 2D animation frames are presented. The scientific novelty of the technological process of gas-dynamic influence developed information model on the melt in a casting mold, implemented by a computer simulation model in the form of a graphic simulator "Virtual Foundry" is noted.

Gas permeability of moulds and cores is an important factor to consider in the casting process. In foundries, gas permeability is measured by using instruments which give dimensionless numbers. Thi...

Numerical simulation technology has been widely used in the foundry industry to analyze and improve casting processes. During the casting filling process, many filling-related defects form easily at the confluences of liquid metal streams. The main filling-related defects are cold shut defects. To calculate the positions of casting defects, the characteristics of liquid metal confluences were analyzed. The flow front of liquid metal was captured by the volume-of-fluid algorithm to obtain a time field, which was used to calculate the time derivatives of the liquid front position and the confluences of liquid metal streams. To distinguish small confluences from the main confluences, the concept of confluent scale was developed, which was used to filter the small confluences based on a threshold. The calculation process was demonstrated through the post-processing of numerical simulation. A “W” shaped casting and a steering wheel casting were calculated to validate the accuracy of the method developed in this study. The positions of cold shut defects were predicted by calculating the confluences of liquid metal streams. The method was proved to be practical by comparing the calculation results with the positions of cold shut defects in an end cover casting. The computation of confluences and cold shut defects can improve the analysis efficiency and provide assurance for the optimization of a casting process plan.

Work-related musculoskeletal disorders (WMSDs) caused due to awkward postures, repetitive motions and handling of loads are the most common ergonomic issues in manufacturing industry. This paper reports the outcome of the ergonomic evaluation of postural loads in small- and medium-scale foundry units using Rapid Entire Body Assessment (REBA) and Rapid Upper Limb Assessment (RULA) techniques. A total of 105 subjects from small- and medium-scale foundry units in western Maharashtra region of India were assessed, and a database was created. REBA analysis is done manually using photographs, and RULA analysis is done using DELMIA-V5 software. The study population is categorized in four departments, and both REBA and RULA analyses indicate that activities from melting and pouring department are at high risk and need immediate intervention. It is found that, in foundry context, the percentage of perfect agreement between REBA and RULA is 75.24%. Suggestions for interventions based on the principles of safety and ergonomics are given. Workers are to be trained to follow the principles of safety and ergonomics during their work to avoid injuries and discomfort due to WMSDs.

We study the influence of decrease in the magnesium content and alloying with scandium, zirconium, manganese, and chromium on the structure, phase composition, strength, plasticity, corrosion potential, and corrosion current in alloys of Al−Mg and Al−Mg−Sc systems obtained with the help of a magnetohydrodynamic foundry. The positive influence of lowering of the content of magnesium and replacement of manganese with chromium in alloys of the Al−Mg−Sc system is demonstrated.

Research is aimed at reducing the energy loss of foundry class arc furnace, which belongs to energy-consuming units with a non-rhythmic work schedule, and characterizes by low energy efficiency. Method of numerical modeling substantiates the concept of furnace modernization, which consists in rising the specific electric power by lowering the capacity at constant productivity, relative increasing of the liquid bath depth, reducing accumulation heat loss by refractory lining through introduction of energy saving water-cooled elements with a spatial structure in its local areas and intensification of heat and mass transfer processes in the "deep" bath with pneumatic stirring. It is determined that for arc furnaces with capacity of 12 and 6 tons, working in one shift, it is rational to reduce the capacity to 6 and 3 tons respectively and the bath shape factor (ratio of diameter to depth) from 5 to 2.5; installation of water-cooled elements in central endurance critical part of the roof and upper parts of the walls with coverage of 0.20-0.32 and 0.5-0.8 of working surface, respectively. With regard to the economy of heating systems, the expansion of the cooling system for the economic efficiency of modernization is 12 tons of chipboard with magnesite lining, so in the small world, dinas lining. For 6 t furnaces of water-cooling elements at the same time the magnesite lining is also effective, the protector is more cheap acidic lining (dinas), however, the water-cooling elements require a larger analogue. With available supply transformer, the specific power increases to 1 MVA/t, which will allow, due to intensification of heat and mass transfer processes, provide quantitative and qualitative indicators of production with lower, compared to the basic unit, heat loss. The implementation of proposed solutions will reduce energy consumption by 75 kWh/t and, taking into account the cost of refractory, provide an economic effect of 320-515 UAH/t

Purpose - Multi Jet Fusion process is based on a polymeric powder bed that is heated and irradiated by infra-red lamps. The layer under construction is jetted with inks to provide the desired heat management conditions for selective melting. Depending on several process variables, manufactured parts can exhibit lifting of the borders of the top surface of the shape under construction. This phenomenon is related to the capillarity effect. As a result, the top surface of MJF-manufactured parts can present a peculiar convex shape. This study proposes a solution that instead induces the capillarity effect outside of the part under construction. Design/methodology/approach - A specific design is developed to avoid the capillarity effect in Multi Jet Fusion. It is based on an analytical model that was previously developed by the authors to estimate the shape and extent of the capillary on top surfaces of benchmark components. The proposed methodology is established by the predicted calculation of maximum values of capillarity rise and length, and safety factors. A fin-shaped geometry is designed to avoid the capillarity effect. An experimental campaign is implemented to verify the effectiveness of the proposed solution. Prototypes are manufactured by an HP MultiJet 4200 in the original design and the so-called finned-riser design, by adding a well- dimensioned appendage on the top surface to shift the capillarity effect outside the border of the part under construction. Measurements are done by a CAM2 ScanArm contactless measuring system to achieve the real shape of top surfaces. Geomagic Control X software by 3D Systems is used to evaluate the quality ofmeasured surfaces in comparison with the expected geometry of the top plane of the benchmark. Findings - The investigated approach involves adding an auxiliary finned-shape appendage, which acts similarly to the risers in foundry technology, to the top surface of the part that is being produced by Multi Jet Fusion technology. The procedure and rules for determining the dimensions of the fin are established based on physical Purpose - Multi Jet Fusion process is based on a polymeric powder bed that is heated and irradiated by infra-red lamps. The layer under construction is jetted with inks to provide the desired heat management conditions for selec- tive melting. Depending on several process variables, manufactured parts can exhibit lifting of the borders of the top surface of the shape under construction. This phenomenon is related to the capillarity effect. As a result, the top surface of MJF-manufactured parts can present a peculiar convex shape. This study proposes a solution that instead induces the capillarity effect outside of the part under construction. Design/methodology/approach - A specific design is developed to avoid the capillarity effect in Multi Jet Fusion. It is based on an analytical model that was previously developed by the authors to estimate the shape and extent of the capillary on top surfaces of benchmark components. The proposed methodology is established by the predicted calculation of maximum values of capillarity rise and length, and safety factors. A fin-shaped geometry is designed to avoid the capillarity effect. An experimental campaign is implemented to verify the effectiveness of the proposed solution. Prototypes are manufactured by an HP MultiJet 4200 in the original design and the so-called finned-riser design, by adding a well- dimensioned appendage on the top surface to shift the capillarity effect outside the border of the part under construction. Measurements are done by a CAM2 ScanArm contactless measuring system to achieve the real shape of top surfaces. Geomagic Control X software by 3D Systems is used to evaluate the quality of considerations and process modelling. The method is then applied to a prototype part, which is designed to highlight the effectiveness of the finned-riser design for improving the dimensional accuracy of the top surfaces of products manufactured by the MJF process. Experimental measurements of top surfaces of the original benchmark are com- pared to the same ones in the case of the finned-riser benchmark. Reported results are satisfactory, the capillary effect occurred in the fins outside the border edges of the part. Further developments are planned to extend the proposed design. Originality/value - Multi Jet Fusion technology is attracting large interest from manufacturers to produce mass customised products. The quality of manufactured parts could be affected by peculiar defects related to process parameters. The present work is showing a method to avoid the capillarity effect. It is based on an original analytical model developed by the authors and imple- mented successfully in the case of a benchmark geometry.

Despite encouraging results, obtained at pilot tests, attempts to substitute the stopper facilities by sliding gates at casting ladles of small capacity, used at foundries of machine-building plants, did not result in their implementation in industry. The problems of transferring casting ladles with a capacity of up to 10 tons to continuous casting of steel, due to the peculiarities of their operation under conditions of obtaining low-weight castings, were considered. Priority problems were noted, the successful solution of which will confirm the prospects of using slide gates in foundry. The main requirements for a steel tapping gate system of a casting ladle of small tonnage are as follows: autonomy of the power supply of the shutter drive, eliminating the need to move flexible hoses over a long distance along the working platform; guaranteed start of casting in normal mode without burning the channel with oxygen; the stability of the node pressing the refractory plates of the slide gate to high temperatures in the absence of forced air cooling; the possibility of an active influence on reducing the intensity of the process of overgrowing of the steel outlet of the ladle in the course of filling molds. As a constructive solution aimed at fulfilling the indicated conditions, it was proposed to use a balancer-type cartridge valve equipped with a modernized electromechanical actuator and auxiliary devices for starting casting in normal mode due to mechanical destruction of the crust at the entrance to the steel outlet channel, as well as heating its walls in the closed state when moving the ladle from one form to another. It was recognized that participation on a parity basis in the creation of a promising sliding gate system for foundry ladles with a capacity of up to 10 tons of several development organizations with practical experience in this technical field is worthwhile.

In recent years, hydroforming has clearly expanded its range of industrial applications due to the growing interest in products which combine high strength with low weight. A current limitation of this technology was its economically justified production volume since the costs of producing tools eliminates the possibility of using hydroforming technology in prototype and single part production. The paper presents a freshly patented solution that allows for single part hydroforming. The new technology combines traditional hydroforming machines with a new approach to tool production. The new rapid die is made quickly and cheaply. The use of materials known from the production of foundry moulds causes the die to deform during hydroforming, but it is a controlled deformation. Thanks to the use of numerical modelling, the deformation of the mould cavity is predicted and taken into account at the design stage. The article presents important issues that need to be considered in the design of this innovative process.

The structure and properties of cold-rolled strips with a thickness of 3 mm from an experimental aluminum alloy 1580 with a lower scandium content of 0.03% (wt.) relative to the grade of the aluminum alloy and a 5083 similar alloy without scandium were studied. Ingots obtained at the laboratory installation of semicontinuous casting of the foundry department of the Siberian Federal University (Siberian Federal University, Russia, Krasnoyarsk) were used. The preparation of ingots for rolling included milling up to sizes of 40 × 100 × 145 mm and annealing according to a two-stage mode: at a temperature of 350 °C for 3 h (first stage) and at a temperature of 425 °C for 4 h (second stage). Hot rolling was carried out in the laboratory of the Department of Metal Forming at the Siberian Federal University at a temperature of 450 °C on a two-roll hot rolling mill with a roll diameter of 330 mm and a barrel length of 520 mm to a thickness of 5 mm, which corresponded to a total reduction of 88% with a single reduction of 2–5%. For cold rolling, a two-roll sheet rolling mill with a roll diameter of 200 mm and a barrel length of 400 mm grade LS 400 AUTO was used. Rolling was carried out to a thickness of 3 mm with a single reduction of 2–5%, and then the strip was annealed. The results of determining the mechanical properties by tension by the universal LFM400 machine showed that with an increase in the annealing temperature in the range from 250 to 350 °C for 3 h, ultimate tensile strength of the cold-rolled strips of aluminum alloy 1580 decreases from 385 to 365 MPa. For aluminum alloy 5083, a decrease in this strength characteristic is also observed from 345 to 320 MPa. A decreasing tendency with increasing annealing temperature was also observed for the conditional yield strength Rp, and over the entire range of annealing temperatures, the values ​​of Rp for strips of alloy 1580 were higher than for alloy 5083 by 35–40 MPa, which amounted to 14–17% The values ​​of the plastic properties, for which the value of the elongation to failure was analyzed, were close throughout the range of annealing temperatures for both alloys. The results of the analysis of micro- and fine structure allowed to conclude that an increase in the strength properties of cold-rolled and annealed sheets from the experimental alloy 1580, compared with alloy 5083, is a consequence of the addition of scandium in the experimental alloy 1580, which leads to an increase in the temperature of recrystallization of the alloy, preserving it contains a subgrain structure and dispersion hardening caused by precipitation of Al3(Sc, Zr) phase particles during the decomposition of a solid solution.

The quality of steel castings was analyzed in this paper through integrated simulations and experiments. The standard tensile specimens were considered as actual cast products. These specimens were prepared using a multi-cavity mold which was initially designed using standards and foundry practices followed by its optimization in casting simulation software MAGMA Soft. The specimens produced with the optimized mold were then tested under tension until fracture. Porosity predicted in casting simulations was integrated to finite element simulations of tensile testing. Simulated and experimental results were compared, discussed, and conclusions drawn. Some specimens indicated discrepancy in the simulated and experimental stress-strain behavior; however, porosity was not found responsible for this disagreement as confirmed through X-ray imaging and by comparing the simulated and actual porosities. It is concluded that the quality of cast specimens is compromised due to ineffective heat treatment which should be done in a more controlled manner for improved quality and performance of castings produced using multi-cavity molds.

3D sand printing is an emerging technology that is enabling new possibilities in metal casting with respect to part complexity, casting design, and rapid mold production. The 3D printing technology, also known as additive manufacturing, is a binder jetting process which involves selectively depositing a furan-based binder into a sand bed one thin layer at a time. Over the course of the process, layers are subsequently added until the entire part has been fabricated. Although the use of 3D-printed sand molds in the foundry industry is growing, significant hesitation to widespread implementation remains. In this work, an investigation was conducted to determine the influence of machine settings on the physical characteristics of 3D-printed sand. Two factorial matrices were constructed to directly measure the significance of six settings that change the resin content and compaction characteristics of the bonded sand. Factors include: X-resolution, printhead voltage, layer thickness, and the frequency, speed, and angle of the recoater blade. Responses include: density, permeability, strength, scratch hardness, loss on ignition, and print resolution. Several relationships are reported between machine settings and physical properties of the product. These results will help inform mold manufacturing as the foundry industry continues to adopt additive technologies.

Purpose This paper aims to investigate the current state, technological challenges, economic opportunities and future directions in the growing “indirect” hybrid manufacturing ecosystem, which integrates traditional metal casting with the production of tooling via additive manufacturing (AM) process including three-dimensional sand printing (3DSP) and printed wax patterns. Design/methodology/approach A survey was conducted among 100 participants from foundries and AM service providers across the USA to understand the current adoption of AM in metal casting as a function of engineering specifications, production demand, volume and cost metrics. In addition, current technological and logistical challenges that are encountered by the foundries are identified to gather insight into the future direction of this evolving supply chain. Findings One of the major findings from this study is that hard tooling costs (i.e. patterns/core boxes) are the greatest challenge in low volume production for foundries. Hence, AM and 3DSP offer the greatest cost-benefit for these low volume production runs as it does not require the need for hard tooling to produce much higher profit premium castings. It is evident that there are major opportunities for the casting supply chain to benefit from an advanced digital ecosystem that seamlessly integrates AM and 3DSP into foundry operations. The critical challenges for adoption of 3DSP in current foundry operations are categorized into as follows: capital cost of the equipment, which cannot be justified due to limited demand for 3DSP molds/cores by casting buyers, transportation of 3DSP molds and cores, access to 3DSP, limited knowledge of 3DSP, limitations in current design tools to integrate 3DSP design principles and long lead times to acquire 3DSP molds/cores. Practical implications Based on the findings of this study, indirect hybrid metal AM supply chains, i.e. 3DSP metal casting supply chains is proposed, as 3DSP replaces traditional mold-making in the sand casting process flow, no/limited additional costs and resources would be required for qualification and certification of the cast parts made from three-dimensional printed sand molds. Access to 3DSP resources can be addressed by establishing a robust 3DSP metal casting supply chain, which will also enable existing foundries to rapidly acquire new 3DSP-related knowledge. Originality/value This original survey from 100 small and medium enterprises including foundries and AM service providers suggests that establishing 3DSP hubs around original equipment manufacturers as a shared resource to produce molds and cores would be beneficial. This provides traditional foundries means to continue mass production of castings using existing hard tooling while integrating 3DSP for new complex low volume parts, replacement parts, legacy parts and prototyping.

Modern metal melting includes of cast iron production in different types furnaces with specific characteristics. Furnaces usually adopted are cupola and induction furnaces. Casting cast iron is a manufacturing process characterized by its energy-intensive nature (ie, the use of large amounts of energy per unit of product for main activities) and a long tradition. An example of the energy balance in a foundry is the design of procedures to reduce energy consumption. The most important is the consumption of energy in the production of hot metals (52%), therefore reducing the cost of preparing hot metal is especially important by reducing the energy consumption of metal melting. The most important energy cost practices are the consumption of hot metal to produce 1mt of high quality castings (often 1700 kg) and reduce the energy consumption of hot metal production that varies over a wide range (from 500 to 1300 kWh/mt). Although scientific and technological aspects are now well established, new studies seem to be needed to describe "foundry of the future", where energy and material efficiency is of great importance to ensure competitiveness alongside environmental protection. The paper presents specific procedures for reducing both economically important indicators in cupola and electric induction furnaces.

Shell moulding is a process for producing simple or complex near-net-shape castings and maintaining tight tolerances with a high degree of dimensional stability. The main objective of the present research is to achieve environmental sustainability by thermal reclamation of the used shell mould foundry sand and present the results of achieving environmental sustainability. The investigations indicate that the thermal reclamation of the used foundry sand helps in achieving sustainability, and the selection of optimal process parameters like percentage of resin, catalyst, and fresh silica sand addition are very important in the shell mould foundry.

Worldwide production of ductile iron castings reached in year 2017 26,428,148 metric tons, which is 34% of the total weight of all castings made from cast iron. The most significant increase in ductile iron castings was recorded in Slovakia, up to 78.6%. Castings from ductile iron have a very huge utilization thanks their very good foundry and mechanical properties. The current economic situation in all industries forces entrepreneurs and producers to rationalize production and reduce production costs, with a worldwide trend to increase the share of steel scrap, a technology for the production of ductile cast iron. The paper describes the results of research focused on the effect of charge composition, mainly the share of scrap steel on the final properties and structure of ductile iron EN-GJS-500-7 under the operating conditions of foundry. Six melts with different charge composition were made. The samples from all melts were taken and chemical analysis, microstructure analysis and testing on mechanical properties were made on them. The mechanical properties of produced globular cast irons were according with the relevant standard. It is important to mention that there has been a significant increase in strength characteristics in melts in which the carbon content exceeded 4% (CE = 4.7 and 4.8%, respectively).

Modernization of physical and mechanical properties of casting alloys, through the introduction of new processes, which can be used to obtain a precise casting with a smooth surface, which does not require machining, with a constant increase in the productivity of the implemented processes, is changing the technological and economic profile of modern foundry. The most advanced equipment is the induction crucible, melting furnace, which belongs to the main production assets and has a direct impact on productivity and, consequently, on profitability. For this reason, it is the main factor determining the content of the development strategies of the enterprise as a whole. Since 2000, iron scrap has been gone, due to the active sale of it abroad, the cost of pig iron and foundry has increased dramatically, in addition, the cost of their delivery increased. This led to higher prices in the production of castings made of synthetic iron, due to the increase in the cost of batch materials. In addition, there were problems with the use of acidic lining, as the cheapest and having a high resistance, as a part of the metal began to use an increased amount of scrap steel and, for this reason, to raise the melting temperature above 1450 Celsius. For this reason, the efficiency of production must be paid great attention.

A high shake-out temperature after casting is beneficial from a production point of view due to the need of a shorter cooling line in the foundry. However, a higher shake-out temperature might also...

Bentonite is the most widely used foundry binder. Most of the iron castings are made in greensand systems which make use of bentonite as a binder. The bentonite used in greensand moulding is usually activated with sodium carbonate to achieve desirable properties. Activation of bentonite is known to improve mould related properties like giving a high wet tensile strength and improving the durability. The practice of activation is more common with calcium bentonite. A number of bentonite deposits tend to remain unbeneficiated due to their low cation exchange capacity (CEC) which are regarded as low quality commercial grade. The primary characteristic that shows the increased activation is the swelling index of the bentonite. This study investigated the influence of rehydration and activation in improving the quality of low commercial grade sodium bentonite. The bentonite samples were activated with sodium carbonate. Rehydration and activation was seen to improve the CEC and swelling index. The increase in CEC and swelling index was however not consistent with the gains in sodium.

There is a need to introduce modern sand binder systems in the South African foundry industry as a means of improving its competiveness through the reduction of scrap castings and compliance to environmental regulations. According to the Industrial Policy Action Plan (IPAP). The foundry industry will play an important role with regards to the economic infrastructure priority advocated in the National Development Plan (NDP) of South Africa. In this study a new generation water glass binder is introduced in a local foundry for production of cores for export plumbing casting production. The new water glass introduced is unique in that it contains an inorganic breakdown agent. The core making operating parameters including binder content, temperature and cycle time are optimised through core making trials without any alterations on the coremaking machines. Production data was evaluated using an optimization feature of Microsoft excel software. The results provided a set of optimum operating variables to manufacture 80-100% good quality sand cores for casting applications with an environmentally friendly binder. The most favourable binder content is above 2.60%.The most favourable operating temperature range is 160–174 °C. Therefore temperature and related energy costs can be reduced. The shortfall is reduction in cycle time.

This paperwork presents the results of a series of experiments on the use of homogenizing annealing, aimed at the possibility to control the structure and properties of steel samples obtained by aluminothermy. This method of processing, in some cases, allows to eliminate the need to use subsequent heat treatment operations due to the achievement of the required properties by the cast blank material. Refractory materials and thermite mixtures used, conditions for the production of castings and their total chemical composition are given. The tensile diagram analysis of the samples before and after heat treatment is presented; the structures and diffraction patterns of the samples’ destruction spots are considered. The material obtained by aluminothermy corresponds in its chemical composition to A1, A2, A3, A4 grade of steels for the rail transport according to GOST 31334-2007 which are used in the manufacture of locomotive axes and other rolling stock.

The purpose of this study was to develop new composites of glass-ceramics from hazardous Cr-Zn galvanic sludge (up to 30%), spent foundry sand (25%), glass rejects from metal surface cleaning (20%), and natural red clay (25%) to produce environmentally clean ceramics. All the raw materials and the developed ceramics were analyzed by XRF, XRD, DTA and TGA, SEM, AAS, and LAMMA. The ceramics showed very high flexural resistance (up to 22.84 MPa) and low values of linear shrinkage (5.02%), water absorption (3.20%), and bulk density (2.00 g/cm3) after sintering at temperatures of 950–1200 °C for 1 h. The solubility and leaching of heavy metals from the developed composites with 75% of industrial wastes were far below Brazilian standards, which makes them eco-friendly materials. Such properties allow the use of the ceramics for the production of facing tiles, roof tiles, blocks, and bricks with high economic efficiency.

The low specific power of the transformer in combination with the increased heat losses due to the geometrical factor and the unstable operation with long downtimes are predetermined by low technical and economic indicators of production, in comparison with the EAF of the "big" metallurgy. An urgent task is to search for low-cost methods to increase the energy efficiency of furnaces of this class by simulating the thermal work of the elements of the working space. Numerical simulation of heat transfer in the working space of foundry class AC EAF with a capacity of 3 tons has shown that with a duration of furnace downtime of 18–20 hours or more, replacing 40% of the walls lining and 16-20% of the roof lining by water cooled elements with a volumetric structure accumulating the skull, with using of “deep" bath with a reduced by 14–15% diameter of the radiating surface allows, at a given melting mass, to reach the energy consumption level of the furnace with a fully refractory lining and lower with a significant saving of refractories. Preloading scrap into the furnace in downtime increases energy efficiency, all other things being equal.

Defects that form during the investment casting of turbine blades for aircraft engines pose a serious hazard to flight safety and greatly increase the costs associated with manufacturing. In this study, we conducted numerical simulations based on a retained melt modulus model to analyze the flow of metals through molds in order to determine the probability of shrinkage defect (PSD) in heat-resistant steel (SCH12) turbine blades for aircraft engines. The results of preliminary simulations and experiments were used to guide the establishment of simulations based on four casting schemes. Our objective in this stage was to identify the casting scheme with the lowest PSD. We then implemented the best of the four schemes with the bottom of the casting system immersed in cold water. We also incorporated virtual thermo-dynamical sensors in the simulations to characterize the effects of water depth on the rate and direction of solidification in the mold cavity. We then applied the optimal investment casting conditions to the fabrication of turbine blades in an established foundry. X-ray analysis detected almost none of the detrimental defects commonly associated with this type of casting, thereby demonstrating the efficacy of the proposed scheme.

This paper presents the development of 1700V-rated 4H-SiC JBS diodes in the state-of-the-art 6-inch SiC-dedicated foundry, NY-PEMC (New York- Power Electronics Manufacturing Consortium). The critical considerations in developing the SiC JBS diode including the cell optimization, edge termination design, process flow, and unit process developments are discussed in this paper. Static device performances such as forward conduction and reverse blocking behaviors of fabricated 1700V, 20A-rated JBS diode are presented.

Optimization of charge burden for foundry furnaces lies in determining a percentage or mass (kg, t) of the share of each charge material in the burden with the lowest unit cost. A classic task of charge burden optimization requires a definition of an objective function, which most often defines the cost of the charge burden and a system of constraints, including technological assumptions such as the balance of chemical elements for the required chemical composition of the charge or molten metal, limitations of the mass fraction of the individual elements of the charge, and others. The solution for such an optimization task is a set of starting values for the devices which weigh and proportion the charge materials for a foundry furnace. The consequences of deviations from proper values, causes by inaccurate weighing or proportioning and human error as well, can be limited by using an appropriately designed and implemented multistage optimization algorithm. This article presents a mathematical model of such an algorithm and discussion of its practical application. The algorithm as described below can be an important element of computer-aided decision to be made by employees in the process of batch compilation or automatically control devices dosing individual batch components. An IT system with an implemented algorithm may significantly increase the efficiency of charge preparation for a foundry furnace, guaranteeing its correct chemical composition despite batch materials dosing errors. It will contribute to a significant improvement of economic indicators of liquid metal production, with the effect of boosting the competitiveness of the foundry industry.

The objective of this study was to investigate the effects of alloying elements on mechanical and thermal characteristic of Al-6wt-%Si-0.4wt-%Mg–(Cu) foundry alloys after heat treatment using a uni...

Assessing of the quality parameters of the blade manufacture, which can affect their operational performance, is an important step in determining the causes of turbine blade destruction. Manufacturing defects, despite their great diversity, tend to be stress concentrators. Apart from the defects listed in the specifications to be avoided upon blade manufacturing, we mean also various kinds of defects identified as concentrators that contribute to the destruction of the blades in operation. Assessment of the blade quality suggests identification and analysis of the defects, as well as determination of the technological stage at which they have been formed. For cooled turbine blades this is the foundry stage of their manufacture. Studies of the blades damaged in operation, revealed that despite the control and rejection of blades in the manufacture, the materials of the turbine blades installed on aircraft engines, contain casting defects. The revealed casting defects are shown to affect the strength characteristics and durability of turbine blades and contribute to their destruction through fatigue fracture in operation. The special features of the quality characteristics of the single-crystal turbine blades, affecting their performance, and defects that contribute to their destruction in operation are highlighted. The necessity of improving the valuation, standardization and quality control both at the stages of design and manufacture of blades is shown.

In this work, real-time in-process monitoring of core motion in metal castings is demonstrated through the use of two emerging technologies. 3D sand printing (3DSP) is a binder jetting additive manufacturing process that is quickly manifesting itself as a technological disrupter in the metal casting industry. Based on its direct digital manufacturing principle, 3DSP enables complex mold and core design freedom that has been previously unavailable to foundry engineers. In addition, the miniaturization and affordability of electronics and sensing equipment is rapidly accelerating. Here, these two shifting paradigms are leveraged together. An experimental casting and mold were designed in this research to demonstrate and evaluate wireless sensing of core shifts. With the use of 3D sand printing, precisely sized and located pockets were manufactured inside of cores. Miniature wireless Bluetooth sensors capable of measuring acceleration and rotation were then embedded inside the cores. From these, high fidelity data were captured wirelessly from the sensors during the casting process. With strategically designed core prints designed to allow varying levels of core motion, it is shown that core shifts can be measured and discriminated during casting in real time.

As a result of a survey of gas exhaust systems of low-tonnage electric arc furnaces (from 3 to 10 tons) operated in the foundries of machine-building enterprises, the bottlenecks were identified, due to which a large amount of gas-dust emissions gets into the production rooms and pollutes the air in the working areas. First of all, it occurs due to the design schemes imperfection of the evacuation systems of gas and dust ejected from the furnace cavity through the outlet channel, the working window, gaps between its body and the roof, between edges of the holes in its upper part and the electrodes lowered through them. In particular, joint units of the rotary collection hoods with the gas exhaust pipelines in these systems do not provide proper sealing of movable joints. In this regard, the authors have proposed an improved design of rotation mechanism of the furnace collection hood, which involves the use of two sand gates. These gates eliminate the possibility of harmful emissions release between movably connected elements of the system into the environment. To begin designing of the industrial sample of a modernized mechanism, a method for calculating the energy-power parameters of its drive has been developed. A preliminary validation of the correctness of the taken technical decisions and of the obtained calculating dependencies was performed on the operating model of the investigated system manufactured on a 1:10 scale relative to the industrial sample. For the model research an instrumentation complex that included strain gauge transducer, AC amplifier, analogto-digital converter and computer was used. During this research the load acting on the model drive of the collection hood rotation mechanism when it was transferred from the working position to the parking one and back was fixed. At the same time, the load was measured for two cases: in the absence and in the presence of sand in the gates which ensure sealing of the movably joint elements of the investigated mechanical system. It was established that the portion of resistance forces arising in two sand gates during relative rotation of the moving element is 20 – 26 % of total load on the mechanism drive depending on angular velocity of the cantilever with collection hood. Similarly, this indicator calculated from obtained theoretical dependences was in the range of 17 – 23 % for the rotation mechanisms of collection hood of arc furnaces with a tonnage of 3 to 10 tons. Video filming of the smoke movement patterns, which flows from the furnace model through the existing gaps between its body and roof during the steelmaking process imitating, confirmed the reliability of the sand gates that provide complete sealing at the joint units of the moving parts of the collection hood rotation mechanism. Practical use of the proposed technical solution allows increasing of efficiency of evacuation of the harmful gas and dust emissions from the working zone of smelting furnaces used in the foundry.

Shrinkage, air hole and some other defects are found in some shell castings of a type of turbocharger products. The root of these defects is detected and analyzed via the simulation work on the filling and solidification process using the Magma foundry simulation software. Two versions of simulation work are completed in total. In the first version, the cause of those defects is highlighted; in the second version, optimization of the casting system is conducted on the basis of the first simulation and analysis work. Those include extending the diameter of the sprue from 46mm to 50mm to get a steady, faster flow, changing the original semi-sphere-shaped sprue base into a cylinder shape, and shortening the filling time from 6s to 5s. Each version of simulation focuses on the temperature variation, velocity variation, the porosity, and the track of the liquid by using the tracer control points. Eventually, after the foundry adopting the second version of casing system, the percentage of unqualified casting products decreased from 20% to about 10%.

—Inspection of the gas-exhaust system at arc furnaces of capacity 3–10 t in the casting shops of manufacturing enterprises reveals problems responsible for copious gas and dust emissions in the production buildings, with degradation of the air quality. This is mainly associated with structural shortcomings of the systems for gas and dust evacuation from the furnace chamber through the exhaust channel, working window, and gaps between the housing and roof and also between the edges of the holes in the upper section and the electrodes within the holes. In particular, the moving joints between the rotary hoods and the gas-exhaust lines in such systems do not ensure reliable sealing. Accordingly, an improved design of the hood-rotation mechanisms has been proposed, with two sand barriers preventing the atmospheric emission of harmful emissions between the moving components. In the design of an industrial prototype, a method is developed for calculating the energy parameters of the drive in the improved system. A 1 : 10 scale model of the system is built to check the design and the theoretical equations. By means of a measuring system consisting of a tensoresistive converter, an ac amplifier, an analog–digital converter, and a computer, the load on the model’s drive on switching from the working position to the rest position and back is determined, for two cases: with and without sand barriers to seal the mobile components. The drag in the two sand barriers on rotation of the moving element amounts to 20–26% of the total load on the drive, depending on the angular velocity of the cantilever with the hood. According to the theoretical formulas, this figure is 17–23% for hood-rotation mechanisms in arc furnaces of capacity 3–10 t. Video recordings of the smoke fluxes from the model through the gaps between its housing and the roof during simulations of steel production confirm the reliability of the sand barriers, which ensure complete sealing of joints in the hood-rotation mechanism. Practical use of the proposed design improves gas–dust evacuation from the working zone of smelting furnaces used in the foundry.

In this work, the effect of solidification rate on the microstructure and impact toughness of high boron high speed steel is systematically investigated. The theoretical and experimental results indicate that the as-cast microstructure of high boron high speed steel consists of α-Fe matrix and eutectic borocarbide. Without Ca-Ti addition, borocarbide presents a continuous and reticular structure. After Ca-Ti modification, borocarbide possesses an isolated, fine structure. Besides, cooling rate obviously affects the extent of spheroidization. In modified high boron high speed steel, calcium possesses surface activity, which restrains the growth of eutectic borocarbide during solidification. Titanium exists in the form of dispersedly distributed TiC particles which act as heterogeneous nuclei for eutectic borocarbide. The impact toughness of high boron high speed steel is remarkably improved by Ca-Ti modification, which can be further improved by cooling rate. The effect of cooling rate on improving of the toughness can provide a scientific basis for the foundry process designing.

Thermal analysis is widely used as a prediction tool for the quality of Al alloys before casting. In the present work, the effects of different grain refiners on the characteristic temperatures and on the grain size of α-Al phase were studied by thermal analysis and metallographic investigations. The response of an AlSiMg alloy towards grain refiners, added in form of rods and tabs, was investigated. In foundry practice, the fading phenomenon of grain refiners is well-known but not completely understood. For these reasons, the fading effect of each refiner at 60 minutes and 120 minutes holding times was also studied. Cooling curves and their derivatives were obtained during solidification of the alloys in a metallic crucible. Experimental data indicated the increase of the temperature associated with the nucleation of α-Al dendrites for the grain-refined alloys in comparison to the untreated ones. Simultaneously, a decrease in primary Al growth temperature, that led to the disappearance of the minimum temperature, were observed. Microstructural features revealed that an increase of 6 ÷ 7 °C of the nucleation temperature, compared to the not refined alloy, corresponds to a significant decrease in average grain size.

Over the last decades, additive manufacturing (AM) has become the principal production technology for prototypes and components with high added value. In the production of metallic parts, AM allows producing complex geometry with a single process. Also, AM admits a joining of elements that could not be realized with traditional methods. In addition, AM allows the manufacturing of components that could not be realized using other types of processes like reticular structures in heat exchangers. A solid mold investment casting that uses printed patterns overcomes typical limitations of additive processes such as expensive machinery and challenging process parameter settings. Indeed, rapid investment casting provides for a foundry epoxy pattern reproducing the component to exploit in the lost wax casting process. In this paper, aluminium radiators with flat heat pipes seamlessly connected with a cellular structure were conceived and produced. This paper aims at defining and investigating the principal foundry parameters to achieve a defect-free heat exchanger. For this purpose, different device CAD models were designed, considering four pipes’ thickness and length. Finite element method numerical simulations were performed to optimize the design of the casting process. Three different gate configurations were investigated for each length. The numerical investigations led to the definition of a castability range depending on flat heat pipes geometry and casting parameters. The optimal gate configuration was applied in the realization of AM patterns and casting processes

In this study, the glass-composite was prepared using glass cullet and waste foundry sand as raw materials. The powder technology route was employed. The mixtures containing 10-50 wt% of the sand were sintered at T = 750 °C for t =1h. XRD and DTA analyses were performed. The chemical durability of the resulting glass-composite was determined by leaching test in HCl, H2SO4, NaOH and distilled water at T = 95 °C for t =1h. It was shown that the sintering process carried out without the crystallization of the glass matrix. The lowest chemical durability was determined in alkali solution of glass-composite.

The description of the heat transfer coefficient represents a core element when defining a system’s heat balance. Especially in foundry processes, high temperature melts get in contact with low temperature molds. While solid-solid contacts have been the focus of numerous investigations, liquid-solid contacts are rarely described in literature. This paper will present and compare different approaches to describe the phenomena and properties necessary for modeling the contact between a liquid melt and a solid mold surface with microscopical roughness. This includes a topographical analysis of the interface and the estimation of the wettability of the surface. The resulting models will determine the heat transfer coefficient for application in thermomechanical simulations of a gravity die casting process. Identifying the model best suited for modeling the melt-mold contact in a foundry process represents the first step towards a physical model that describes the entirety of a casting process.

This article is devoted to the problem of reducing the number of defects and improving the quality of manufacturing gas turbine engine blades. The process of pressing a casting rod designed to form the inner cavity of the blades during their manufacture by pouring on the smelted models is considered. Information about 400 examples of pressing foundry rods has been collected. Each of the examples contained a set of parameters that characterize the process of obtaining the workpieces and the result of manufacturing. Based on the collected statistical information, the neural network was designed. Using virtual computer experiments, the process of pressing casting rods was studied. The parameters that have the greatest impact on the quality of the resulting products are identified. In the course of computer experiments, it was observed that changes in a number of pressing parameters which lead to a decrease in the probability of defects on one billet do not lead to a similar decrease in the probability of defects on another billet. The method of neural network modeling was able to identify parameters the same change in which leads to a decrease in the probability of any type of defect of all workpieces. For example, the probability of getting defects in all workpieces decreases with increasing the holding time of the rod in the mold without pressure. Thus, it is shown that the developed neural network model allows to control the quality of the obtained blades, select the optimal parameters of the technological process that provide the maximum reduction of defects.

Designing optimal material flow into a semiconductor inter-bay handling’s layout boosts production efficiency, increases yield and throughput, and cuts work-in-process (WIP) as well as cycle time. Intelligent layout of production plants is vital for modern manufacturing, and particularly so for 450-mm wafer-size semiconductor plants. In light of the particular bay nature of a semiconductor plant’s inter-bay, its shortcut design that results on more efficient flow movement become challenging differed from those of a manufacturing system. Additionally, a semiconductor bay’s shortcut layout considerations must address not just how to group stockers, but also how to determine the type of shortcut points and sequence of shortcut locations. Prior to mass production, the assessment expressed by designers’ artificial language, linguistic variable, for the shortcut design phase remains ambiguous and subjective. The need for efficient ways to take designers’ linguistic variables into account in the layout decision increases. The present study suggests a method based on fuzzy set theory to design the shortcut location for a semiconductor inter-bay equipped with a multiple-zone overhead shuttle (OHS) handling system. Unlike traditional layout approaches which can only handle quantitative data with Boolean logic problems, fuzzy-set-based methods offer a way to incorporate the attitude of designers using linguistic variables to represent a problem in decision making when designing semiconductor bay’s shortcut layout. The paper also develops an intelligent hybrid heuristic algorithm incorporating with the goal of maximizing in-sequence movements and minimizing total flow distance to search a better shortcut layout design. An illustrative example from a wafer foundry company is used to demonstrate that the fuzzy-set-based layout design found by the proposed layout method outperforms by other approaches in the OHS travel time, throughput, and flow time performance. The method suggested here can assist semiconductor facility designers in qualitatively and quantitatively improving the material flow and increasing production efficiency by solving their semiconductor bay’s shortcut layout problems.

Defects in cast metals remain a common problem in many areas of the foundry industry, particularly in the investment casting of large area, thin-walled components for aerospace applications. During previous research, the thermophysical properties, density and porosity of a fibre reinforced ceramic investment casting mould were determined using several experimental techniques. Without verification, these experimental results remain nothing more than educated guesswork. The purpose of this study is to verify previous results and to more fully characterise the ceramic mould material with complementary measurements. A commercially available computational fluid dynamic (CFD) simulation package, Flow-3D®, was used in conjunction with a full-scale Ni-superalloy (IN718) casting to assess the accuracy of these results. By placing thermocouples strategically across the mould thickness, temperature profiles were determined and compared directly to predicted profiles extracted from the simulation by a custom-written Python script. Funding details: Engineering and Physical Sciences Research Council, EPSRC; Funding text 1: The authors would like to thank the Engineering and Physical Sciences Research Council (EPSRC) and TPC Components AB for providing their financial support towards this research. In addition, The authors would like to specifically thank Daniel Kuivamäki (TPC Components AB) and personnel of the Flow 3D® support team for their technical support with the computer simulations. The data used in this paper is described in the Cranfield Online Data Repository (CORD) at: http://doi.org/10.17862/cranfield.rd.9934280