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Sand casting method is used to produce many useful products for many applications. The aim of the study is to manufacture a product with excellent dimensional geometry is achieved in sand casting process at low cost. We would expect manuscripts to show how design and/or manufacturing problems have been solved using computer modeling, simulation and analysis. In this work, the important mechanical properties of hardness and surface roughness are investigated on Aluminum 6063 cast material with and without incorporating the copper tubes as a vent hole in sand casting process. Since copper has high thermal conductivity when compared to other metals, the heat transfer rate will be varying from existing system. The copper tubes have made different diameters of holes on outer surfaces with selective distance of intervals. The specific number of copper tubes with various diameters are designed by CATIA modeling software and analyzed with Taguchi Design of Experiment. Taguchi L9 orthogonal array is used proficiently in the optimal value of hardness and surface roughness. The results are revealed that the maximum hardness value of 104 BHN is attained for 10mm distance of holes made on copper tube with an angle of 90o degree. The minimum surface roughness of 2.11 micron is achieved for 20mm distance of holes made on copper tube with 45o of angle as a vent hole in sand casting process.

Porosity defects and interfacial reaction are very serious problems in sand casting Al–Li alloy, which greatly affect the quality of castings. In this work, the characteristic and formation mechanism of the porosity defects in the sand casting Al–Li alloys were systematically investigated by scanning electron microscopy, transmission electron microscopy, energy spectrometry, and inductively coupled plasma mass spectrometry, in order to provide a theoretical basis for the prevention and control of the pore defects in the sand casting Al–Li alloys. The results found that the Al–Li alloys prepared by metal mold and graphite mold as casting molds had almost no pore defects and interfacial reaction layers, with the porosities of 5.81% and 5.05%, respectively, while the sand casting Al–Li alloys with furan resin, phenolic resin, and sodium silicate binder as binders all had serious pore defects and interfacial reaction layers, with the porosity of 15.67%, sharply weakening the mechanical properties of the Al–Li alloy casting. The types of the pore defects were mainly reactive pores and intrusive pores, and the interface reaction layer was mainly composed of LiAlO2 and C–H–O organics. The formation mechanism of the pore defects in the sand casting Al–Li alloys was caused by the reaction between Li and the hydroxyl groups in the binder of the sand mold to generate a large amount of hydrogen, which intruded into the melt or was sucked into the melt.

A series of studies related to the production of organobentonite, i.e., bentonite-poly(acrylic acid), and its use as a matrix grain-binding material in casting moulding sand is presented. In addition, a new carbon additive in the form of shungite was introduced into the composition of the moulding sand. Selected technological and strength properties of green sand bond with the obtained organobentonite with the addition of shungite as a new lustrous carbon carrier ( R c w , R m w , P w , P w , P D ) were determined. The introduction of shungite as a replacement for coal dust in the hydrocarbon resin system demonstrated the achievement of an optimum moulding sand composition for practical use in casting technology. Using chromatographic techniques (Py-GC/MS, GC), the positive effect of shungite on the quantity and quality of the gaseous products generated from the moulding sand during the thermal destruction of its components was noted, thus confirming the reduced environmental footprint of the new carbon additive compared to the commonly used lustrous carbon carriers. The test casting obtained in the mould of the organobentonite moulding sand and the shungite/hydrocarbon resin mixture showed a significantly better accuracy of the stepped model shape reproduction and surface smoothness compared to the casting obtained with the model moulding sand. [ABSTRACT FROM AUTHOR]

Compound casting is a process in which a single component is made from two metallic materials, such as aluminum and steel. Solid-liquid bimetallic compounds can be produced by suitable process control. This technology can reduce the number of joining processes, and the specific properties of the respective metal component can be used for specifically designed product properties, for example, where lightweight and high strength are needed. This paper presents an experimental methodology for producing a purely material-bonded bimetallic joint from cast aluminum and zinc-coated sheet steel in 3D sand casting using an inductive heating system. The process-related temperature characterisation in the compound zone is described using a heating test rig and temperature measurements. It shows that inductive preheating can only produce a material bond between the aluminum casting and the coated steel sheet. Shear tensile tests showed strengths between 15 MPa and 22 MPa. Laser surface pre-treatment using laser ablation cutting on the coated steel sheet was carried out to investigate the benefit of possible microform-locking. The results show a strength-reducing influence on the tensile shear tests. Micrographs showed the formation of Al4.5FeSi and Al7Fe2Si, as well as the formation of other undefined intermetallic phases. The thickness of the compound zone is 10 µm. [ABSTRACT FROM AUTHOR]

This work presents a mathematical tool to estimate the cost of fabricating pumps by traditional casting. The drivers that most affect the cost of the process are identified in each step of the procedure, i.e., material, labour, energy, tools and general expenses associated with any industrial activity. The mathematical expressions used for the calculation of the different cost drivers are presented and used to estimate the cost of fabricating the different parts composing a radial pump in a small Moroccan foundry. Therefore, the input data of the equations carefully consider the economic factors of this country. However, the developed tool is versatile and can be adapted to describe the casting process in other countries with different economies just by changing the input data accordingly. It is observed that the influence of the drivers in the final cost of the pump is very dependent on the number of pumps to be produced. In any case, the cost estimation tool presented in this work will allow for the optimization of the yield of the casting process rendering the involved company more reliable. The tool provides an idea of the implications of changing production factors, allowing the foundry to give accurate and fast responses without compromising its profits. [ABSTRACT FROM AUTHOR]

Arbomex S.A. de C. V. is one of the largest worldwide manufacturers of ductile cast iron camshafts, produced by means of the phenolic urethane no-bake sand mold casting method and cold box by stack molding technology. As a result of the development of high-strength ADIs, low alloyed with vanadium, for camshaft manufacturing, previous results were published on the as-cast process and the austempering heat treatments applied to the camshafts. In the present work, camshafts of ADIs, low alloyed with 0.2 and 0.3 wt.% V, were produced at austempering temperatures of 265 and 305 °C. The performance of the new camshafts was evaluated by wear testing to ensure the function and durability of the camshafts by means of the block-on-ring wear test and a valve train system to evaluate the volume loss of material removed and the geometrical changes of the camshaft, respectively. The ADIs heat treated to 265 °C showed a microstructure constituted of fine ausferrite that aided in obtaining the highest wear resistance in the block-on ring wear test. No wear or pitting evidence was detected on the camshaft lobes and roller surfaces after the OEM test protocol during the electric spin ring test at low and high conditions for the ADI alloyed with 0.2 wt.% V heat treated at 265 °C. [ABSTRACT FROM AUTHOR]

Turbulent filling of molten metal in sand-casting leads to bi-films, porosity and oxide inclusions which results in poor mechanical properties and high scrap rate of sand castings. Hence, it is critical to understand the metal flow in sand-molds, i.e., casting hydrodynamics to eliminate casting defects. While multiple numerical methods have been applied to simulate this phenomenon for decades, harsh foundry environments and expensive x-ray equipment have limited experimental approaches to accurately visualize metal flow in sand molds. In this paper, a novel approach to solve this challenge is proposed using Succinonitrile (SCN) as a more accurate metal analog in place of water. SCN has a long history in solidification research due to its BCC (Body-Centered-Cubic) crystal structure and dendrite-like solidification (melting temperature ~60 °C) like molten aluminum. However, this is the first reported study on applying SCN through novel casting hydrodynamics to accurately visualize melt flow for casting studies. This paper used numerical simulations and experiments using both water and SCN to identify the critical dimensionless numbers to perform accurate metal flow analog testing. Froude's number and wall roughness were identified as critical variables. Experimental results show that SCN flow testing was more accurate in recreating the flow profile of molten aluminum, thus validating its utility as a metal analog for metal flow research. Findings from this study can be used in future metal flow analysis such as: runner, in-gate and integrated filling-feeding-solidification studies. [ABSTRACT FROM AUTHOR]

The object of research in the work is the technology of manufacturing shaped castings in disposable sand molds. The existing problem is that the imperfection of design and technological solutions at the stage of developing the technology of a single sand mold casting leads to deviations in the dimensions and geometry of the castings after their manufacture from the requirements of technological documentation. This can lead to an irreparable shortage of casting. To develop measures to eliminate or minimize the event, which consists in the formation of a shortage of castings in terms of dimensional and geometric accuracy, a procedure for searching for optimal design and technological solutions is proposed. A hypothesis has been put forward that a significant factor that leads to deviations in the dimensional and geometric accuracy of castings from the requirements of technological documentation is the imperfection of the gating system design. It is demonstrated on specific castings how this factor can influence the formation of uneven wall thickness. The proposed procedure, which includes 10 consecutive steps, allows to build a plan for a complete factorial experiment and obtain a regression equation for it, linking the parameters of the gating system with indicators of dimensional and geometric accuracy. The presence of such equations provides the possibility of further experimental optimization and determination of design and technological solutions for the development or improvement of casting systems that minimize the deviations of the dimensional and geometric accuracy of castings from the requirements of technological documentation. This also minimizes the likelihood of an event consisting in the formation of an irreparable shortage of castings. The presented study will be useful for machine-building enterprises that have foundries in their structure, where shaped castings are made in disposable sand molds. [ABSTRACT FROM AUTHOR]

Casting Alloy Data Search (CADS) AFS through AMC/DLA has developed a very effective web-based tool called Casting Alloy Data Search (CADS) for design engineers and ICME professionals which has been used for over five years by foundry professionals and which is accessible through the AFS website. AFS directly funds research projects from the allocation of a portion of annual dues paid by AFS Corporate Membership. Web-Based Events AFS also offers a series of technical webinars open to all industry personnel (offered at no cost to AFS members) that provide relevant information presented by industry experts on a wide variety of metalcasting subjects. AFS Information Services Casting Process and Alloy Assistance The American Foundry Society website (www.afsinc.org) provides tools to assist casting design engineers in selecting the best casting process for a potential component, as well as casting alloy property data on many commonly used alloys. [Extracted from the article]

One of the most interesting capabilities of ablation technology is its capability to manufacture uncastable alloys such as alloys of the 5XXX and 6XXX aluminium series. Two conventional wrought alloys with relatively low alloying content were selected aided by thermodynamic simulation to be manufactured by ablation casting technology. Two different grain refiners were tested and compared to unrefined melt alloy. A fine grain size of 0.25–0.30 mm was achieved. The refinement effect was clearly identifiable by thermal analysis technique for both alloys. The density index value and macroinclusion test grades were used to validate the low hydrogen content and the metals' cleanliness. Thus, an optimized chemical composition and melt treatment are defined for 5154 and 6061 alloys suitable for manufacturing by ablation technology. For comparison, 6061 alloy was also cast in a conventional sand mould. [ABSTRACT FROM AUTHOR]

To evaluate the enhanced erosion wear performance under acidic medium, a new high-vanadium–chromium alloy (HVCA) is designed and test samples produced by sand casting. The microstructure was analyzed by SEM, TEM and XRD. The erosion wear performance was tested in acidic medium designed by orthogonal test method. The factors affecting the erosion wear performance of HVCA are analyzed. The research results show that microstructure of HVCA is characterized by different carbides (M7C3, M23C6, VC, M2C) distributed in martensite and residual austenite. The hardness is 65.16 ± 0.2 HRC, and the impact toughness is 9.82 ± 0.12 J/cm2. H2SO4 concentration has the greatest influence on the erosion wear performance of HVCA, followed by the erosion wear angle. The maximum erosion wear performance of HVCA is 1.59 times that of HCCI. Compared with HCCI, HVCA has excellent erosion wear resistance because of its high hardness and toughness, a small amount of fracture and carbide shedding, and slight corrosion and wear interaction under erosion wear condition. [ABSTRACT FROM AUTHOR]

During the past several decades, significant progress has been achieved in establishing the proper values of casting process variables to enhance casting quality utilising a variety of methodologies. One of the most important factors in casting quality is the design of the sand-casting process variables. The optimization of green sand-casting factors has been studied and analyzed in several journal and conference papers, as well as research by professional associations and institutions; a few of them are summarized below. [ABSTRACT FROM AUTHOR]

In this study, the ability to control the thickness and composition of surface alloyed layer on mild steel (produced by coating the surface of the mold with metal powders) has been demonstrated. The surface alloying process was conducted during lab-scale sand casting by coating the mold surfaces with slurries containing Ni, Cr, Fe-Si, and Fe-Mn as alloying powders. Two different compositions of surface alloying powders were tested for their level of enrichment and effect on the properties of Wrought Carbon Grade B (WCB) steel. The powder quantity per unit area of mold surface was varied to control the thickness of the surface alloyed (SA) layer between 1000 and 4000 microns; the thickness varied linearly with the amount of powder per unit area. The microstructure, composition, and phases of the alloyed layers were characterized for a few selected samples. The presence of austenite, ferrite, and limited chromium oxide was observed in the surface alloyed layers by x-ray diffraction (XRD). Limited testing of surface alloyed samples showed an increase in the hardness and corrosion resistance as compared to WCB steel substrate. These improved properties can lead to an increase in the life of the cast components with a minimal increase in the production cost. [ABSTRACT FROM AUTHOR]

The increasing demand and exorbitant use of river bed sand in foundries over the years have led to its depletion at an alarming rate. Consequently, many states in India have imposed severe restrictions on the mining of riverbed sand. Therefore, an effort is made to explore the potential use of sea sand for cast iron foundry applications. Experiments were performed for optimizing the composition of molding sand with respect to functional properties namely, strength, mold hardness, and permeability. The optimum composition of molding sand comprised of 8.33 wt% bentonite and 3.12 wt% moisture, and 88.54 wt% sea sand. Trials were conducted in a local foundry to ascertain the suitability of using a mixture of sea sand, bentonite, and water for producing defect-free gray iron casting. The trial was successful and parts were accepted for production purposes. [ABSTRACT FROM AUTHOR]

In foundry production, the duration of metal crystallization of the cast part, as well as the distribution of the thermal field, are described by systems of analytical equations. There are a number of methods for modeling these processes, but their theoretical basis was formed at the end of the twentieth century, and it needs to be updated and clarified. Therefore, the aim of our work is to develop a new analytical method for researching the distribution of thermal fields in cast parts during crystallization. For the first time, on the basis of own analytical and thermophysical developments, it developed the analytical method for researching the thermal field of the casting during crystallization and cooling, which is based on establishing the kinetics of cooling of the casting surface in the foundry mold, the advancement of the crystallization front from the surface to the center of the casting, and the distribution of temperatures in the solid and liquid parts of the casting. The method is expressed in a number of analytical formulas, each of which describes the specific thermal process that occurs in the casting. The developed analytical method was used to research the crystallization of the casting in a one-time sand mold, using the example of researching the thermal field of the cast part made of carbon steel with 0.25% C, hollow cylindrical shape, with the wall thickness of 100 mm. The developed analytical method for researching the thermal fields of cast parts is the analytical basis for the refinement of applied computer programs for modeling crystallization and cooling processes in foundry production. [ABSTRACT FROM AUTHOR]

The feasibility of using Laser Selective Melting(SLM) to prepare AlSilOMg profiled parts for civil aircraft was studied and discussed, and its performance was evaluated and compared with that of castings. The results show that the SLM formed AlSilOMg alloy has dense structure, superior mechanical properties to ZL104 castings and AlSilOMg sand castings with equivalent composition, slightly better lateral plasticity than vertical, and slightly better vertical tensile strength than horizontal. When the laser scanning power and other parameters are unchanged, the alloy with ideal microstructure and no obvious metallurgical defects can be obtained. The manufacturing process and parameters have passed the airworthiness compliance verification of CCAR25, which provides a solution for the manufacturing of civil aircraft shaped parts. [ABSTRACT FROM AUTHOR]

We have developed a casting process termed HMPAC (hot mold with progressive ablation cooling) process that, for the first time, is capable of producing a large thin-walled casting of high integrity using only one feeder. The ductility of such castings of A356 alloy was investigated using this new process. For comparison, conventional sand casting of the same size, and conventional porosity-free permanent mold casting and extrusions were made and their mechanical properties were measured. Experimental results indicated that the ductility of the castings made using the HMPAC process was much higher than that of the conventional casting processes and was only slightly lower than that of extrusions. Such a high ductility of the castings made by this new process was due to the fact that shrinkage porosity was totally eliminated and the eutectic silicon was totally modified from flake-like to fine fibers owing to the water quench effect. Numerical simulation revealed that, at a given ablation velocity, the interdendritic feeding distance was reduced by increasing mold temperatures. T6 heat treatment could break up the silicon fibers into isolated particles. It is expected that the ductility of the large thin-walled casting made by this HMPAC process could be further improved towards the ductility of extrusions by optimizing process parameters. [ABSTRACT FROM AUTHOR]

The wave field in solidifying metals is the theoretical basis for analyzing the effects of mechanical vibration on solidification, but there is little research on this topic. This study investigated the wave field and its effect on the solidification feeding in the low-pressure sand casting (LPSC) of Al-Cu-Mn-Ti alloy through experimental and numerical investigation. The solidification temperature field was simulated by AnycastingTM, and the wave field was simulated by the self-developed wave propagation software. The shrinkage defect detection showed that applying vibration had a greater promotional effect on feeding than increasing the holding pressure. The predicted defects under vibration coincided with the detections. The displacement field showed that the casting vibrated harmonically with an inhomogeneous amplitude distribution under the continuous harmonic vibration excitation, and the vibration energy was mainly concentrated in the feeding channel. With solidification, the u x amplitude reduced rapidly after the overlapping of dendrites, finally reducing slowly to a certain level; the u y amplitude reduced dramatically after the occurrence of a quasi-solid phase, finally reducing slowly to near zero. Mechanical vibration produced a severe shear deformation in the quasi-liquid phase—especially in the lower feeding channel—reducing the grain size to promote mass feeding. The feeding pressure and feeding gap were changed periodically under vibration, causing the vibration-promoting interdendritic feeding rate to fluctuate and eventually stabilize at about 13.4%. The mechanical vibration can increase the feeding pressure difference and change the blockage structure simultaneously, increasing the formation probability of burst feeding. [ABSTRACT FROM AUTHOR]

This research is an experimental comparison study to show the influence of mold type casting on mechanical properties. The study considers the aluminum alloy of a gasoline engine piston with nanoparticles alumina Al2O3 size 25 nm manufactured in two types of molds. Sand mold and cast-iron mold were selected to cast the aluminum composite components. A systematic comparative study of tensile strength and hardness properties of cast aluminum components is made on sand and metal molds production. The nano powder can add to enhance the mechanical properties must not exceed 4 % for metal and sand mold casting. According to data for hardness, adding nano alumina powder has minimal impact on metal mold casting, but it significantly improves sand casting. From a financial standpoint, metal casting provides higher economic values for making piston aluminum castings. The hardness rises as the alumina content does in two molds as compared to the obtained specimen. It demonstrates that the highest hardness occurs at 4 % alumina in the sand-casting mold and at 6 % alumina in the metal. When the compositions of the casting materials are the same, a comparison of the fracture morphology between sand and mold casting reveals more ductile fractures for metal molds compared to brittle fractures in sand cast by large silicon separation grains because of higher grain growth in sand casting by longer solidification time. The same is seen in mold casting, which exhibits reduced ductility due to the alumina nanoparticles’ dispersion strengthening process in the aluminum matrix. This arises as a result of nano alumina dispersion acting as barriers to dislocation motions in the aluminum matrix, enhancing strength but reducing ductility. [ABSTRACT FROM AUTHOR]

• A new concrete material, compression cast SS-SW concrete, was developed to face the challenges of raw materials shortage and severe service environments. • The compression cast SS-SW concrete was experimentally demonstrated to have remarkable advantages over normal cast concrete at both macro and micro levels. • Existing models for elastic modulus, peak strain and stress-strain curve are inadequate for predicting the behavior of compression-cast SS-SW concrete. • For the first time, new, accurate and reliable models were developed to predict the entire stress-strain response of compression-cast SS-SW concrete. Reinforced concrete (RC) structures in coastal and marine regions face two primary challenges, the shortage of raw materials and severe service environments. Concrete made from sea sand and seawater (SS-SW) can address the shortage of natural sand by utilizing locally available resources. Meanwhile, the newly developed compression cast technology (CCT) significantly improves the micro and macro properties of concrete, enhancing its durability in harsh environments. Therefore, the combination of SS-SW concrete and CCT to form a new compression-cast SS-SW concrete can simultaneously solve the problems of materials shortage and durability issues for coastal RC structures. However, till now, research on this type of concrete is still an open issue. This paper aims to carry out multilevel investigations on the macro and micro performance of compressed SS-SW concrete. First, 69 concrete columns were tested to understand the stress-strain behavior and associated mechanical indices. The compressive strength of compressed concrete was found to be up to 1.86 times greater than that of uncompressed concrete. Meanwhile, the porosities in both mortar and the interfacial transition zone (ITZ) of concrete under a casting pressure of 15 MPa were approximately 50 % of those in uncompressed counterpart. Existing models are inadequate for predicting the behavior of compressed SS-SW concrete, leading to the development of new and accurate models to predict its compressive strength, elastic modulus, peak strain and stress-strain curve. These findings pave the way for the design and application of this kind of concrete. [Display omitted] [ABSTRACT FROM AUTHOR]

The technique of differential impedance analysis (DIA) has shown promising results in identifying appropriate model orders when applied to electrochemical impedance spectroscopy (EIS) measurements of a given medium. However, even with this method it remains challenging to reliably deduce general material properties of the medium from impedance data alone. Here, we discuss a number of possible extensions and modifications of the technique and, in particular, an extension of the process from mere model order identification to a complete modelling approach. In addition, the combination of DIA and machine learning methods to predict material properties is explored. Our results were validated with impedance measurements between 20 Hz and 1 MHz of moulding sand containing varying amounts of quartz and chromite sand as well as bentonite and carbon. [ABSTRACT FROM AUTHOR]

Silica sand is the most commonly used aggregate in the green sand molding process. This study examines the feasibility of copper slag (Cu slag) as a substitute for commercial-grade silica sand in the green sand mold casting process. The major composition of Cu slag is silica, ferric oxide, and alumina. The central composite design within the framework of response surface methodology (RSM) is a quintessential method and used for the optimization of mold constituents of Cu slag molds. The RSM model predicted 3.1 wt% moisture and 11.2 wt% bentonite clay in the Cu slag mold to achieve the required mold properties. The mold properties of the Cu slag mold such as hardness, permeability, compressive strength, and shear strength were evaluated. The model predicted mold properties are validated experimentally. The experimental results show that the mold's hardness, permeability number, compressive strength, and shear strength are 94, 351, 1.31 kg/cm2 (0.128 MPa), and 0.39 kg/cm2 (0.038 MPa), respectively. The Cu slag mold properties are benchmarked with commercial-grade silica sand mold. An A356 aluminum alloy casting was made using silica sand and Cu slag molds. The as-cast properties, like hardness, surface roughness, and microstructures, are evaluated and compared between commercial-grade silica sand mold and Cu slag mold casting products, and found a good agreement between them. Therefore, Cu slag molds may be used in the green sand mold casting process. However, its recyclability and sustainability need to be ensured before used it commercially. [ABSTRACT FROM AUTHOR]

Casting aluminum alloys is widely used in aerospace, rail transportation, automotive, ships, and other fields. The frozen sand mold casting (FSMC) technology provides a greener and low-cost solution for the sand mold casting industry, which has a better operating environment than the resin sand mold casting and a higher degree of subcooling for solidification process. The interfacial heat transfer coefficient (IHTC) is a significant parameter that affects the structure and properties of the frozen casting. It is also an important boundary condition in numerical simulation. In this paper, a frozen sand mold casting (FSMC) process thermal conductivity problem (IHCP) inversion model is proposed based on the 1-D heat transfer assumption using a combination of finite difference method (FDM) and conjugate gradient method (CGM). The inversion model is validated for its rationality and accuracy in terms of experiments and numerical calculations, respectively. The IHTC is determined under various frozen sand mold casting conditions, including different initial frozen temperatures, water contents, and molding sand. The accuracy of results is verified by comparing the experimental and numerical data. A new method is provided for determining IHTC in frozen casting. [ABSTRACT FROM AUTHOR]

Niyama and solid fraction criteria are used to predict the solidification porosity and microporosity in computing simulation of casting processes. The solid fraction permits us to determine the areas that solidify last and that are a candidate for presenting porosity if a feeding system is not correctly designed. The Niyama criterion is locally obtained based on the thermal and cooling gradients at a point of the liquid casting. The Niyama value at a casting point varies rapidly from low rates to high ones during the last part of the metal solidification, which demands that the percentage of solidification of the metal is defined to determine the Niyama number. In addition, the Niyama threshold that establishes the soundness of the workpiece can vary according to the nature of the metal or the casting system. In this paper, a methodology to determine the solidification percentage is presented. The method is based on the Niyama number evolution during the solidification process at different key points. These points are validated by the solid fraction criterion as healthy or, on the contrary, as candidates for containing porosity. In addition, some considerations of the solid fraction criterion are visited since the threshold value for which the isolation of the last solidification areas can be defined is not clear. The research is validated by the empirical casting criteria existing in the literature for obtaining sound parts and applied to low-carbon steel bars produced by sand casting.

he sand casting process still continues today due to the cost-effectiveness of materials and processes. There is a wide variety of castings related to composition and size, but silica sand is widely available from coastal line mining and has a negative impact on the environment. Moreover, waste from waterjet cutting of non-ferrous and ferrous metals is practically unhazardous and may potentially be used in sand casting mould. The aim of this paper is to optimize the proportion of coal dust, water and bentonite added to the silica sand mixture and the waterjet cutting abrasive waste as a new way of handling waste with the potential to be used in sand casting manufacturing. The method used was L9 orthogonal array optimization and the composition was qualitatively measured using a green compression strength test and a green shear strength test. Factors were evaluated using the analysis of variance (ANOVA) to find the the critical factors while confirmation test was conducted for the optimal material proportion. The study concluded that the ideal ratio for silica sand mixture with waterjet abrasive waste is bentonite-12%, coal dust-5%, and water-7% for green compression strength while bentonite-12%, coal dust-6%, water-7% for green shear strength. With proper selection, the incorporation of waterjet abrasive waste into the green sand mixture is promising to potentially be used in green sand mould casting without undermine the quality of mould.

The shrinkage defects of Al-Cu-Mn-Ti alloy seriously hinder its application in high-performance engineering. In this study, mechanical vibration was introduced to low-pressure sand casting (LPSC) by a waveguide rod to eliminate shrinkage defects and improve mechanical properties. Four LPSC castings were performed by changing the solidification conditions: 20 kPa solidification pressure without and with 14 Hz vibration and 40 kPa without and with 24 Hz (the natural frequency of a casting system) vibration. The shrinkage defects, microstructures, and mechanical tensile properties at room temperature and at 2 mm/min tensile rate were investigated. X-ray detections showed that applying vibration was more effective than increasing solidification pressure in improving solidification feeding, while the most effective method was applying both simultaneously, which eliminated the shrinkage defects and increased the density by 2.7%. Microstructures exhibited that the average size of primary α-Al grains were reduced by 29.5%; mechanical tests showed that the ultimate tensile strength and the elongation increased by 21.7% and 7.8%, respectively, by applying vibration and increasing the solidification pressure simultaneously, as compared to the casting with 20 kPa solidification pressure without vibration. Mechanical vibration was conducive to mass feeding by refining the primary grains, to interdendritic feeding by reducing the threshold pressure gradient, and to burst feeding by collapsing the barrier. [ABSTRACT FROM AUTHOR]

A new lightweight vertical bar plate was developed by inserting individual bars into the plate base rather than the typical sand casting method. The lightweight vertical bar plate has a very sharp bar edge because vertical bars are inserted instead of trapezoidal bars. The refining effects of the mixed stock with softwood bleached kraft pulp (Sw-BKP) and hardwood bleached kraft pulp (Hw-BKP) were compared using two types of lightweight vertical bar plates with cutting edge lengths of 55 km/s (PA55) and 97 km/s (PB97). The fine bar plate (PB97) with large CEL (PB97) was very effective in reducing the refining energy required to reach the final freeness regardless of the mixing ratios of Sw-BKP and Hw-BKP compared to the plate with a small CEL (PA55). PB97 also consumed less refining energy than PA55 until proper sheet strength was achieved. In particular, irrespective of the mixing ratios of Sw-BKP and Hw-BKP, the tensile strength of sheets at the final freeness was greater in PB97 than in PA55. For stock throughput during refining, PA55 with the wide groove was almost similar to PB97 with the narrow groove. [ABSTRACT FROM AUTHOR]

The gating and riser system design is essential for both quality and cost in large-scale casting and is expected to reach several objectives simultaneously. However, even with the help of commercial simulation software, the design of gating and riser systems is still the result of a long-term trial-and-error optimal process owing to the conflict between the objectives. Several evolutionary algorithms (EAs) have been reported to be helpful in the selection of the geometrical dimensions of gating and riser systems. In this study, a route with sequential use of a multi-objective EA and single-objective optimization algorithm was developed to help design gating and riser systems, respectively. This route was applied in an actual case and verified using commercial simulation software. The results showed a dramatic decrease in the time cost in design and acceptable casting quality. Thus, the proposed design method is time-saving. [ABSTRACT FROM AUTHOR]

Compressibility of Expanded Polystyrene (EPS) beads in mixtures of sand and EPS beads is considered by discrete element modeling of beads as clumps of particles bonded by a cohesive contact model. A calibration scheme is devised where input microparameters are calibrated stepwise, using experimental results and available data. The calibrated model is used to investigate the effect of parameters, namely normal pressure, EPS bead content and bead relative size on the compressibility and lateral stresses of the mixtures. Results showed an increase in mixture compressibility with the addition of EPS, which coincided with an increase in total coordination number. The increase in EPS bead size was observed to decrease compressibility. Microscale results showed a reduction in the overall, EPS-EPS and sand-EPS coordination numbers with the increase in bead relative size, resulting in the contact network being more dominated by sand-sand contacts which resulted in stiffer mixtures. However, this reduction in compressibility was negligible for larger EPS bead contents where coordination numbers showed that enough contacts are formed between EPS beads to create a continuous network across the sample, thus curtailing the effect of EPS bead size. Contact force networks showed that despite the increase in the number of sand-EPS and EPS-EPS contacts, the majority of forces are transferred through sand-sand contacts. [ABSTRACT FROM AUTHOR]

AFS directly funds research projects from the allocation of a portion of annual dues paid by AFS Corporate Membership. Open to all industry personnel (offered at no cost to AFS members), web-based seminars provide relevant information presented by industry experts on a wide variety of metalcasting subjects. 34th Environmental, Health and Safety Conference (October 4-6, Milwaukee, WI): The annual AFS Environmental, Health & Safety Conference is the singular event for foundry industry EHS professionals to network, benchmark, and learn from each other. Casting Alloy Data Search (CADS) AFS through AMC/DLA has developed a very effective web-based tool called Casting Alloy Data Search (CADS) for design engineers and ICME professionals which has been used for over five years by foundry professionals and which is accessible through the AFS website. [Extracted from the article]

Due to the high demand for secondary alloys in the automotive and aerospace industry, this work investigates the effect of higher iron content on the quality of AlSi7Mg0.6 sand castings. Secondary-recycled Al-Si alloys contain an increased amount of impurities due to their remelting of scrap metal. One of the most unwanted impurities found in these alloys is iron. Iron leads to the formation of various Fe-rich intermetallic phases, whose morphology influences the mechanical properties even at low Fe content. It also promotes the formation of casting defects, such as porosity and shrinkage. The formation of porosity in secondary Al-alloys is another major aspect that can affect the final properties of castings. Since these materials are mainly used to produce castings for the automotive industry, such as engine blocks, cylinder heads, and so on, it is necessary to produce castings without any defects. Therefore, the quality of AlSi7Mg0.6 sand casting is investigated at lower iron content (0.128% wt. Fe) and compared to the higher iron content (0.429% wt. Fe), whereby a correlation between iron content and porosity is monitored. [ABSTRACT FROM AUTHOR]

In this study, the effects of different types of investment casting waste sand were investigated in porcelain tile production in place of clay and kaolin. Dry and firing shrinkages, water absorption, dry and firing strengths and densities of porcelain tile bodies were determined. In addition, color measurements, XRD analysis and SEM analyses of the relevant samples were also investigated. A1, A2, A3, B and C porcelain tiles had higher density, firing shrinkage and firing strength values. However, they had lower water absorption, dry shrinkage and dry strength values than those of the reference porcelain tile. Quartz, mullite and albite were found in all the bodies as main phases and, in addition, zircon phase was determined in bodies in which waste sand was incorporated. [ABSTRACT FROM AUTHOR]

Sand molding casting has been widely used for a long time. But, one of its main drawbacks is that surface quality of the castings is not good enough for some applications. The purposes of this research were to investigate the effect of addition of sawdust ash of rubber wood (SARW) on molding sand properties and the surface quality of iron castings and to find an appropriate level of SARW with the appropriate properties of the iron castings. The molding sand compositions for making a sand mold consisted of the recycled molding sand, bentonite, water and SARW. The percentage levels of SARW were 0%, 0.1%, 0.2%, 0.3% and 0.4%. The different proportions of molding sand samples were investigated for the molding sand properties including permeability, compression strength and hardness. The results showed that addition of SARW had an effect on the molding sand properties. The appropriate percentage proportion of molding sand was obtained at 95.8% recycled molding sand, 0.8% bentonite, 3% water and 0.4% SARW. There were statistically significant differences of mean surface roughness and hardness values of the iron castings made from molding sand samples without SARW addition and the appropriate percentage proportion of molding sand. In addition, the average surface roughness value of the iron castings made from the sand mold with the appropriate percentage proportion of molding sand was ~40% lower than those of the iron castings made from molding sand samples without SARW addition. [ABSTRACT FROM AUTHOR]

Material suppliers typically recommend different additive amounts and applications for foundry practices. Therefore, even in the production of the same standard materials, different results may be obtained from various production processes on different foundry floors. In this study, the liquid metal prepared with the addition of different proportions of a FeSi-based inoculation, which is most commonly used in foundries in the production of a cast iron material with EN-GJL-250 lamellar graphite cast iron, was cast into sand molds prepared with a model designed to provide different solidification times. In this way, the optimization of the inoculation amounts on the casting structure for different solidification times was investigated. In addition, hardness values were determined depending on solidification time in varying amounts of inoculation additions. SolidCast casting simulation software was used to determine the casting model geometry and solidification time. In the scope of the study, sand casting, modeling, microstructure analysis, image analysis, microstructure analysis, and hardness tests techniques were used. When the results are examined, the required amount of inoculation for the optimal structure is optimized for the application procedure depending on the casting module and the solidification time. [ABSTRACT FROM AUTHOR]

The aim of the study was to select the optimal content of zirconium introduced as an alloying additive to obtain the best strength properties of Al-Si alloy. A technically important disadvantage is the tendency of silumins to form a coarse-grained structure that adversely affects the mechanical properties of castings. To improve the structure, modification processes and alloying additives are used, both of which can effectively refine the structure and thus increase the mechanical properties. According to the Hall-Petch relationship, the finer is the structure, the higher are the mechanical properties of the alloy. The proposed addition of zirconium as an alloying element has a beneficial effect on the structure and properties of silumins, inhibiting the grain growth. The starting material was an aluminium-silicon casting alloy designated as EN AC-AlSi9Mg (AK9). Zirconium (Zr) was added to the alloy in an amount of 0.1%, 0.2%, 0.3%, 0.4% and 0.5% by weight. From the modified alloy, after verification of the chemical composition, samples were cast into sand moulds based on a phenolic resin. The first step in the research was testing the casting properties of alloys with the addition of Zr (castability, density, porosity). In the next step, the effect of zirconium addition on the structure and mechanical properties of castings was determined. [ABSTRACT FROM AUTHOR]

In traditional casting, sand is used as a mould material to carry heat away from the melt. However, sand has certain disadvantages, such as poor thermal conductivity, burning of binders, undesirable transition resulting in mould failure, and defects in the components. To overcome these limitations, magnetic moulding technology was introduced more than a few decades ago, but the process never achieved the required industrial developments to commercialise this technology. It is essential to reconsider and develop this technology further to use it as a regular production process. In this paper, processing of Al/SiCp composite using magnetic moulding technology is discussed. The heat transfer results of magnetic moulding process are simulated using COMSOL Multiphysics software and compared with the sand casting process. The temperature distribution, thermal conductivity, and phase change have been studied, finding that steel shots as mould materials show better heat transfer results when compared with sand. This better heat transfer led to a decrease in solidification time by 25%, which in turn improved the hardness (by 70%), impact toughness (by 4 times), and wear resistance (by 42%) of the Al/SiCp cast produced. These results very clearly illustrate the unique signature of the magnetic moulding process. [ABSTRACT FROM AUTHOR]

Metal castings with the presence of shrinkage porosity are often recycled or rejected and in turn reduce productivity of the process as well as increase energy cost involved in the process. This can be overcome by prevention of its occurrence using a suitable prediction technique. A detailed study of literature reveals that several Criterion Functions (an empirical model that connects solidification phenomena with formation of shrinkage porosity) have been employed to predict the location of shrinkage porosity in castings manufactured using particular process-alloy combination by values of process parameters (mostly thermal gradient, cooling rate, and velocity of molten metal). However, criterion function considering the effect of geometric variation in stainless steel castings on an extent of shrinkage porosity need to be established. In the present work, a benchmark casting, a combination of three T junctions, has been cast and used for the development of geometry-driven criterion function for stainless steel castings. Real experimental results with the presence of shrinkage porosity were used for superimposing on virtual experimental results (simulated results) for establishment of local simulation conditions. These conditions are further used in extrapolating results using casting simulation. The developed geometry-driven criterion function was further validated and found to be effective in prediction of shrinkage porosity. [ABSTRACT FROM AUTHOR]