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In the industry, electric spark cutting is a key cutting operation because it can efficiently cut both hard and difficult-to-work-with materials using traditional methods. The primary goal of this study is to investigate the influence of four copper electrodes (Gost 1173) on the wear rate of a titanium alloy (Grade 1), where three electrodes were coated with different materials (nickel, silver, and gold). The (full factorial design) was used to design the experiments, and the actual results revealed that the electrode wear rate reduces as the discharge current and pulse on time increase, and vice versa. Furthermore, the predicted results are extremely near to the practical side results. [ABSTRACT FROM AUTHOR]

Electrical discharge machining (EDM) is a non-traditional machining process that includes removing material from a part using a series of repetitive electrical discharges in the presence of a dielectric fluid between electrodes and the component being manufactured. EDM is one approach for manufacturing geometrically complicated or hard-to-machine objects. Its distinctive advantage in the creation of molds, dies, automotive, aviation, and medical interventions has been the application of thermal power to make conducting electrically pieces regardless of toughness. In this review paper, we look at how various Nano composite electrodes are manufactured and different dielectric fluids are used in EDM to machine harder materials, as well as the most essential technological characteristics: MRR, EWR and Surface Roughness. [ABSTRACT FROM AUTHOR]

The "Composite material" is composed of a discrete reinforcement and Distributed in a continuous phase of matrix, In Aluminium matrix composite (AMC) one constitutes is Aluminium which forms network that is matrix phase and another constitute serve as reinforcement which is generally ceramic or nonmetallic hard material. The basic reason of metals reinforced with hard ceramic particles or fibres is to improve the properties than its original material properties like strength, hardness etc. Stir casting process is mainly used for manufacturing of Particulate Reinforced Metal Matrix composite (PMMC). Manufacturing of aluminium alloy-based Casting Composite by stir casting is one of the most economical methods of processing MMC. Properties of these materials depend upon many processing parameters and selection of matrix and reinforcements. This project presents an overview of stir casting process, process parameter and preparation of AMC material by using LM 25 Aluminium as matrix form and SiC as reinforcement by varying its proportions. [ABSTRACT FROM AUTHOR]

Usually, negligible factors in macro- or miniature size materials such as grain-size effects, may not be neglected in micro-forming processes. Studies had shown that material behaviour varies greatly with the increasing of the scale in the micro-forming world. Therefore, in every micro-forming-related process, especially in micro-stamping, studies and analyses of each material used for the process must be considered as indispensable in order to be able to understand their behaviour and to be able to correlate their behaviour with the process. Uniaxial tensile-testing experiments have been carried out to determine the sheet's properties, behaviour and its correlation with the feeding process in micro-stamping/micro-sheet-forming application. Based on the results of the uniaxial tensile-test experiments conducted, the flow stress was found to decrease with the decrease of the sheet thickness and vice versa, due to the size/scale effect. A surface model was used to explain the findings. It is known that surface roughness has some correlation with friction. Therefore, surface-roughness measurements and the coefficient of friction between contact pairs also have been determined in order to study the correlation between the two quantities. [ABSTRACT FROM AUTHOR]

In past few decades, magneto crystalline hard magnetic materials have attracted considerable attention in scientific and technological applications due to their thermal, mechanical and chemical stability including anisotropy, magnetization, coercivity, resistivity, dielectric constant and curie temperature. Magnetic materials are useful in minimizing the electromagnetic interference problem as well as help in increasing the storage capacity. In this respect, emphasis was given on the preparation of ultrafine nanoparticles and provides an over view of hexaferrites synthesized by using solid-state reaction. The effect of dopant on various properties was discussed in detail because the tuning of structural, electrical, morphological and magnetic properties in desired range make these materials useful in high frequency devices. [ABSTRACT FROM AUTHOR]

Cutting-edge machining techniques have recently been widely utilized to address a variety of problems in the manufacturing industry, such as machining higher strength materials, producing intricately curved profiles, improving surface properties, and reducing production time. Electro Discharge Machining (EDM) is quickly developing in this situation. EDM is a popular advanced machining process for cutting hard materials and alloys with superior surface quality and dimensional accuracy. This thorough review research offers an insight on the chosen input process variables, responses, workpieces machined, as well as optimization methods used in those operation while producing varied component shapes for industrial application based on recently published EDM process papers. It is discovered that the identified process parameter with the greatest importance is pulse-on time (Ton), that material removal rate (MRR) and surface roughness (SR) are the two prevalent output characteristics, that various steel grades are the most commonly workpieces, and that grey relational analysis (GRA) is the ubiquitously employed technique for optimization of EDM processes parameters. These findings will assist process engineers in optimizing the machining performance of EDM processes for various work material and shape feature combinations. Furthermore, the closing remarks highlight the stated underlining and technical gaps in research, enabling this present review valuable to the connected academia and scientific research communities with the correct assessment of EDM process parameters, advanced workpieces, tools, and sustainable dielectric for attaining favourable results as futuristic advanced machining technology. [ABSTRACT FROM AUTHOR]

With the significant growth of cutting tool technology, the machining of hard to cut material is the main discussed area among academic researchers and metal-cutting industries. Higher-speed machining conditions have been adopted by many researchers nowadays. Considering the environmental aspects, the issue of adopting Minimum Quantity Lubrication (MQL) is still a challenging issue. Along with the MQL machining conditions, various types of solid lubricants have been used to improve machining performance. Thus, the present review presents on a concise review of different machining conditions with various cutting tools and their machinability indicators for superalloys. The research findings are very interesting that are relevant to the industry. However, there are still some issues to be explored in the coming days that are in line with the future research direction. The knowledge gained from this survey and future studies in the fields of sustainable machining will assist a wide range of disciplines, from design development to materials synthesis. The research community can gather from this review survey which direction the machinability improvement trend is moving in various machining processes. [ABSTRACT FROM AUTHOR]

Machining has become a major cutting operation for producing various complex geometrical components in manufacturing industries. The challenging situations during the cutting process often occur when deals extra hard materials. In this current study, the effect of soaking time on the physical, microstructural, and mechanical properties of the alumina ceramic cutting insert was examined. The pure alumina powder was pressed using a uniaxial hydraulic hand press set at 200 MPa into pellets and sintered at 1600 °C with different soaking times of 10, 30, 50, 70, 90, 110 and 120 minutes. According to the current findings, the rising trends of the density value were recorded from 3.8468 g/cm3 at 10 minutes of soaking time until it reached a maximum value of 3.8983 g/cm3 for 120 minutes of soaking time. As a result, the lowest porosity has been achieved at the highest soaking time, which was recorded at about 0.340%, due to better adhesion and bonding within the particle. Therefore, the prolonged soaking time significantly showed the increment of hardness and indentation fracture resistance (KIFR) of 1667.91 HV and 6.35 MPa.m1/2, respectively. [ABSTRACT FROM AUTHOR]

The most promising substance that offers the maximum mechanical strength in the world of hard machining materials is aluminium alloys. Because of its superior strength to weight ratio, it is widely used in the fabrication of aerospace and aeronautical products. Eco-friendly and cost-effective machining techniques have become increasingly necessary over time, and many researchers have expressed a strong interest in developing ever-more-advanced machining techniques. The proper selection of the machining technique and cooling circumstances are crucial since they have an impact on performance when working with aluminium alloy materials. This article provides a detailed study on the various researches carried out in last few years towards optimization of machinability studies involving optimization tools and techniques. It captures the methodology adopted by various researchers and their outcomes. [ABSTRACT FROM AUTHOR]

This research is about the comparison of novel TiN coated and uncoated carbide tools in CNC wet turning of EN31 to maximize material removal rate. Materials and methods: Work material used was EN31 tool steel and cutting tools used was novel TiN coated and uncoated carbide tools with the tool designation of CNMG120408 (Make: Widia). The three input parameters selected for present experimental study are cutting speed (m/min), feed (mm/rev) and depth of cut (mm), each parameter varied at 3 different levels and L9 experimental runs are conducted. Two groups of experimental study are selected (novel TiN coated and uncoated) with 27 samples per group. On the whole 54 samples were collected and measured for 2 groups. Result: Material removal rate obtained on the novel TiN coated carbide tool is maximized when compared with the uncoated carbide tool by 3.8% during machining of EN31 tool steel. The obtained mean value for coated carbide tool was 83.75789, and for uncoated carbide tool was 943.68333, The results are statistically analysed with the use of a SPSS software and graphs were plotted and its level of significance was found to be 0.041 (p<0.05). Conclusion: By the limitations of the study we can conclude that for the machining process of the selected hard material like EN31 steel tool, by using a novel TiN coated carbide tool, material removal removal rate has been maximized when compared to the uncoated tool during CNC turning operation. [ABSTRACT FROM AUTHOR]

World has come across various natural transformations and process which has its own pros and cons. Metals are widely used in the world for multiple reasons in which the materials are hard, lustrous, malleable used commonly in construction industry, technology development, medicinal products, space researches etc. A natural transformation process caused by essential phenomena like water, air and gaseous things which leads to an electro-chemical action called corrosion. The corrosion causes cautious destruction to the metals by attacking it through various chemical and electro-chemical processes. Corrosion of reinforcing steel and other embedded metals is the leading cause of deterioration in concrete. When steel corrodes, the resulting rust occupies a greater volume than the steel. This expansion creates tensile stresses in the concrete, which can eventually cause cracking, delamination, and spalling. This report aims to access and determine the range of corrosion in a reinforced structure by half-cell potentiometer with different reference electrode to get the accuracy between the them, impressed current technique is used for acceleration of corrosion. The experimental study includes the compressive strength, flexural strength and tensile strength tests are also conducted for the designed concrete sample in the grade of M20. [ABSTRACT FROM AUTHOR]

A wheel is a circular frame of hard material that is intended to rotate on an axle bearing. The alloy wheels have always been a subject of interest among high performance bikers. A lot of research work has been going on the different alloy materials and design for the wheels. Now a days most of the bikes coming with high engine power. So the wheel rim need to withstand high speed and forces caused by path holes and sudden braking. The main objective of our project is to design spoke patterns that focus on reducing the stresses, total deformation in the wheel. In this project we are designed different types of spoke patterns using CATIA V5 software and finding the best suitable spoke pattern. The design model can be analyzed under static structural conditions using Ansys workbench software. We analyzed the designed wheel pattern by modifying the spoke pattern, radius at the intersection of the spoke and hub in the design. By analyzing the design model on Ansys workbench using carbon steel 1008, aluminum 356 and carbon fiber materials we found maximum stress, total deflection and equivalent strain in the wheel rim under static structural conditions. The boundary conditions that we applied on the wheel are pressure on the circumference on the wheel rim, force at the center of the wheel and fixed support at the wheel hub. In this paper we had compared the different spoke patterns under static conditions. We are also comparing the spoke patterns under three different materials (carbon steel 1008, aluminum 356, carbon fiber). We can conclude best wheel pattern and best suitable material used for wheel rim. [ABSTRACT FROM AUTHOR]

The Ba1-xSrxFe12O19 (x=0, 0.2, 0.4, 0.6, 0.8, 1) ferrite nanoparticle have been prepared via chemical co-precipitation process. Ferrite formation and morphology were measures via field emission scanning electron microscopy energy-dispersive X-Ray diffraction (FESEM-EDX). The samples ferrite nanoparticle prepared were characterized with vibrating sample magnetometry (VSM), and the measurements shown the following that unique magnetic distinction at (x=0.6, 0.8) samples where saturation magnetization reaches to (86.035, 85.633) emu/g and residual magnetization (39.8, 39.342) emu/g while in (x=0, 1) saturation magnetization was (77.7, 83.640) emu/g and residual magnetization (34.763, 38.469) emu/g. The hysteresis loop was found and show that, structure consisted of hexagonal nanoparticles and the samples of hard ferrite materials. [ABSTRACT FROM AUTHOR]

In the automotive sector, composite materials that help improve fuel efficiency, reduce pollution, and improve performance are in great demand. To improve fuel economy, it is critical to minimize the vehicle's overall weight. Materials are continuously enhancing as a necessity of human society, and progress from all materials over their broader classifications is a significant research demand. For modern-day technology needs and to create a product at the lowest feasible cost, which is a common customer requirement, research for upgraded materials is always a hot topic. To meet safety and operating criteria, new materials are created on a regular basis, and material features are modified to keep up with current technological breakthroughs. Composites have grown steadily from their infancy to their maturity. Composite materials are in great demand and consumption all over the world due to their vast range of applications. It has already been recognized the need for the development of harder lightweight materials with high performance and efficiency in a variety of industries. Aluminium metal matrix composites (AlMMCs) are a boon to product designers looking for lightweight, medium-strength, and low-cost materials. AlMMCs is being hailed as a promising new generation of materials for a variety of purposes of technical applications. Reinforcing with a range of materials, AlMMCs have a lot of promise for creating composites with the properties required for specific applications. According to demands and application requirements, AlMMCs have been produced to provide superior mechanical and tribological properties while still being lightweight. In this study, the application of AlMMCs is briefly presented. [ABSTRACT FROM AUTHOR]

Fluids used for metal cutting have a massive negative effect on human fitness and surrounding bionomics, thereby giving rise to a serious risk to the reliable evolution of the international manufacturing industry. Rejection or replacement of conventional lubricants results in the depletion of cost for operation as well as there will be an impact on environment related with the use, refinement and disposal of fluids for metalworking. Although, conventional lubricating processes are still extensively used while machining materials which are "difficult to cut", with the point to improve the life of tool and acquire a better surface roughness. The machining with lubricants is commonly executed on the hard to cut materials. It has been revealed that more than 85% of the lubricants applied in metal cutting sectors for cutting are mineral-based that are extremely toxin. Since we know that more than two-thirds of the lubricants for disposals returns to the surrounding with no process of purification, thus, requisite procedures are demanded to decrease the consumption of fuel. Moreover, less injurious variety of lubricants should be recognized and used. This paper presents an analysis on a number of papers published with reference to its application with various types of vegetable oils which is considered as a biodegradable oil used as a cutting fluid when machining superalloys. [ABSTRACT FROM AUTHOR]

The use of proper geometrical feature of cutting tool can improve machinability of hard material such as titanium alloy. In addition, machining titanium alloy leads to localized temperature increment at the machining zone, and their reactivity with most cutting tool materials becomes a problem for machinist. The objective of this study is to relate the effect of differential pitch angle and margin presence of end mill in terms of machining performance when end milling titanium alloy Ti6Al4V. In this study, side milling with the implementation of minimum quantity lubrication (MQL) technique was investigated. Cutting temperature and cutting force during machining were observed. Tool T2 recorded 24% increment of cutting temperature and 48% increment of cutting force compared to tool T1. From the results of cutting temperature and cutting force, Tool T1 is better compared to tool T2 due to the presence of geometrical design features. [ABSTRACT FROM AUTHOR]

Without proper geometrical feature of end mill cutting tool, it causes poor surface integrity of machined workpiece especially when handling hard machine material such as titanium alloy. The main drawback when machining titanium alloy is the high tendency of temperature generation at the cutting zone due to properties of Ti6Al4V itself, subsequently impairing the cutting tool life. Therefore, the objective of this study is to compare the performance of differential pitch angle and margin presence of end mill when end milling titanium alloy in terms of surface integrity. The milling type used was side milling with the implementation of minimum quantity lubrication (MQL) technique. Two different geometrical features of end mill were designed to improve the performance. Mean surface roughness, Ra, subsurface deformation and microhardness were observed during side milling process. From the results, T2 tends to improve the Ra of machined workpiece, subsurface deformation and microhardness by 24%, 28% and 0.7%, respectively, when compared with T1. T2 outperformed T1 due to the presence of differential pitch angle and cylindrical margin. [ABSTRACT FROM AUTHOR]

Coatings, such as monolithic and multi-layer coatings, have been used in protecting bearing surfaces. A monolithic coating is a type of basic coating using one type of material while a multi-layer coating is a coating consisting of a combination of soft and hard materials. Although monolithic coatings can improve wear resistance, they can fail due to infiltration and rapid crack expansion. In addition, multi-layer coatings can lower the coefficient of friction and bear heavy loads with a combination of hard and soft materials; however, an increase in the coefficient of friction and temperature will occur when the thickness of the coating is too high. Therefore, multi-layer hierarchical coating will be introduced as it can provide continuous transition with different combinations and thicknesses to overcome the problem of bond strength between layers. ANSYS Mechanical APDL was used to study very high, high, medium, and low hierarchical coatings with nano- indentation simulation. Next, the overall mechanical properties of the multi-layered hierarchical coating will be obtained through inverse and regression methods. The load-displacement curves for multi-layered and monolithic hierarchical coatings (overall mechanical properties) obtained an error of less than 10 %. All specimens had similar hardness except for the low hierarchy. The study also proves that multi-layer hierarchical coatings do slightly influence the mechanical and wear properties compared to conventional coatings based on the inverse and regression methods. In the future, nonlinear regression is proposed for further studies in which it will describe a more suitable relationship for nanoindentation. In addition, more data are also proposed to improve the accuracy of the regression results generated. [ABSTRACT FROM AUTHOR]

Electro chemical micro Machining (ECM) is a promising unconventional technique used as one of the alternatives to conventional machining processes for machining such as hard materials and complex profiles without the stress and no tool wear. The ECM has wide-ranging applications in automobile, aerospace, process industry, medical industries. Studies on MRR are of greatest importance in ECM, since it is one of the influential factors in making process decisions. The ECM has gained its importance due to increased surface quality because of no contact between tool and work piece and ability to produce complex geometrical shapes. Among the various non-conventional machining processes, ECM is considered as one of the important process due its advantages such as, its applicability nevertheless of hardness of the materials, higher MRR, no tool wear, good surface finish and absence of thermal or mechanical stress in the work piece material. In this research work micro ECM will be carried out on the Brass CZ108. It can hold strength and resisting oxidization at extreme heat and it is chemically inert. Micro ECM will be carried out by changing the electrodes. Copper electrode is selected for Micro ECM process. [ABSTRACT FROM AUTHOR]

Machining hard materials in high-speed machining is a knowledge area that needs further investigation due to its promoting contribution to machining knowledge and its advantages in reducing time to the market. Chips as one of the tangible outputs can explain many aspects of the machining processes. This research aims to study the chip morphology during high-speed end milling of hardened steel AISI D2. To achieve the study's objective, a set of experiments were conducted to analyze the chip morphology on hardened steel AISI D2 in high-speed end milling at different cutting parameters. The effect of various levels of cutting speed (from 120 to 240 mm/min), feed rate (from 0.05 to 0.15 mm/rev), and depth of cut (from 0.10 to 0.20 mm) were analyzed and investigated. The image of chips collected is examined and investigated utilizing Scanning Electron Microscope (SEM). The results show that the cutting speed and feed rate are the most influential independent factors on the final chip formation in high-speed end milling of hardened steel AISI D2. [ABSTRACT FROM AUTHOR]

The properties of the material surface are developed by different mechanical processes. Shot peening is used to develop compressive stress in the surface of the material and thereby improve fatigue life, hardness, and resistance due to stress corrosion of the material without changing the material composition. The surface is also modified by carburizing and nitriding heat treatment process of steel components and the surface become hard with changing the material composition of the surface. Friction surfacing, the latest technology, is applied for the development of parts surface in which coating of different materials is formed over the other material to prevent wear and corrosion, to improve mechanical properties and reconstruct the damaged surface. The domain of application for friction surfacing is quite large than that of shot peening. The surface is deformed plastically during shot peening but modified Thermomechanically in friction surfacing. The shot peening is controlled by a lot of parameters such as density and hardness of shot, size of the shots, time of exposure, angle of impact, no of passes, the distance between nozzle and workpiece, linear as well as the rotational speed of workpiece with respect to nozzle whereas friction surfacing can be controlled by a less number of parameters like the rotational speed of mechtrode, downward axial force on the consumable rod, the horizontal speed of the substrate, operating time and angle of tilt. Also, composite materials can be formed by friction surfacing. The number of layers of the deposited material over another material surface during friction surfacing can affect the properties of the surface also. The present paper explains both the processes of surface development regarding industrial application and their recent development. The advanced shot peening processes such as laser peening, nano-peening are also discussed. [ABSTRACT FROM AUTHOR]

The purpose of the research was to determine the visitor's perceptions of child-friendly spaces and to know the public spaces needed by children on the Losari beach. To answer the research, this research is a qualitative research with descriptive analysis and the technique of taking is done by purposive sampling. Likert scale is used to calculate visitor perception. The findings of the study are that visitors do not agree with several things in the Losari beach as public space such as not preparing children's rooms for both play and facilities that are in accordance with the characteristics of children, the use of the environment as a playground that can endanger children and make other visitors uncomfortable. hard materials are dominant on the Losari beach pavilion, good waste management, trash cans, and no smoking room. In general, the public space on Losari beach cannot be used as a suitable space for children because the space is not suitable for their characteristics and in accordance with the criteria required by the Kementerian Perlindungan Perempuan dan Anak Republik Indonesia (KPPA). [ABSTRACT FROM AUTHOR]

Soil borehole drilling with standard penetration test (SPT) is a conventional method for a subsurface profiling that able to determine soil bearing capacity. However, full investigation of high accuracy on the subsurface with additional boreholes is strenuous. This method is invasive and time consuming. The multichannel analysis surface wave (MASW) was used in this investigation to test the dependability of this method and potentially converting shear wave velocity, Vs, to SPT-N value. The dependability of the correlation between actual and calculated SPT-N value was high (R2 = 0.7256) by utilizing Vs values using the specified equation (Vs = 97N0.314). Throughout regression analysis, the SPT-N value can be determined based on the generated equation 0.0114Vs1.3721 in the form of power allometric. Hence, allowing the equation to be applied for the local region. A field study was conducted, and Vs profile revealed 80 m/s to 160 m/s of the upper layer at 2-3 m depth representing soft soil, followed by a 2 m layer of stiff soil with Vs in between 130 m/s and 170 m/s, then 4-10 m hard material with Vs in between 190 m/s to 280 m/s, before reaching a harder stratum of 350 m/s and more. As a result, the soil properties were determined and used for soil bearing capacity and factor of safety (FOS) of the slope calculation. Thus, MASW can be executed to determine SPT-N values providing supporting data to the conventional approach. Although, it is consider in the preliminary stage, the developed empirical equation in this study is intended to give a rapid preliminary approach and general view of the profile prior to site investigation/assessment for the geotechnical engineers. [ABSTRACT FROM AUTHOR]

As an elective for conventional machining of hard materials and complex shapes without harming the devices and residual stresses, electrochemical machining has been advanced. This study examined the impacts of processing parameters on the Material Removal Rate (MRR) and the overcut (OC) of a custom-built electrochemical machine. Unmasked and masked aluminum plates with 0.5 mm thickness as workpieces were machined by an ECM with an outer diameter of 5 mm and 1 mm thick brass tube as an electrode in sodium chloride as an electrolytic solution. Tests were carried out using the advanced construction by altering the workpiece-to-electrode gap with a constant device movement of 0.375 mm/minute and 7-volt voltages. MRR in ECM was attained from weight loss measurement, whereas to determine the OC, open-source software (ImageJ) for image analysis was utilized. The results revealed an increase within the machining gap decreased mobility and conductivity of ions for conduction, causing lower MRR and overcut. Masked workpieces depicted lower MRR and OC but smoother in surface finish. [ABSTRACT FROM AUTHOR]

In this study, the Die Sink electric discharge machining (EDM) of titanium alloys Ti6Al4V and Ti5553 with copper electrode material were conducted to find the optimum process parameters and to compare machinability of these alloys on sink EDM for same input design. The design of experiments was conducted using Taguchi method to find the optimum machining parameters such as current (I), Pulse on time (Ton) and Pulse off time (Toff) for various response parameters such as Material removal rate (MRR), Surface roughness (Ra) and Radial over cut (ROC). Mean effect plots and S/N ratios have been used to optimize the machining parameters of Die sink EDM on Ti6Al4V and Ti5553 using the Taguchi method. ANOVA is performed to find the percentage contribution of each input parameter on each output variable. The experimental results reveal that Ti5553 material machinability on sink EDM w.r.t metal MRR, Ra and ROC is better compared to Ti6Al4V material, this signifies the factor that Die sink EDM is best suited for harder materials. [ABSTRACT FROM AUTHOR]

Currently increasing the cutting tools durability is an urgent problem. The high cutting conditions required to improve processing performance place special demands on tool materials. During the cutting process the tool working surfaces are subjected to intense exposure to high contact pressures and temperatures. Interaction with the processed material leads to an intensification of the adhesion, diffusion, and oxidation processes. All this causes rapid wear of the cutting tool. To reduce wear and prevent destruction the tool material must have high hardness, heat resistance, wear resistance, and strength. Hard and super-hard materials are used as tool materials for high-speed cutting, but their production is very expensive. Therefore it is more appropriate to apply coatings on the tool working surfaces in order to form the required properties. The article substantiates the need for the use of wear-resistant coatings on the working surfaces of cutting tools made of tool steels. A number of promising trends in the development of protective coating application technologies for cutting tools have been considered in the review. [ABSTRACT FROM AUTHOR]

Nickel-based alloys like Inconel 718 occupy a large share in the aerospace industry because of superior mechanical properties. However, Inconel 718 is categorized as a difficult to machine material. Ultrasonic assisted grinding (UAG), a hybrid grinding process has captured the attention of researchers for grinding of Inconel 718 due its inherent capability in overcoming several problems associated with processing difficult to grind (DTG) materials. Lubrication machining is used for hard to machine materials and minimum quantity lubrication (MQL) is a sustainable method employed to overcome machining problems in such materials. In this context, this work aims to examine UAG of Inconel 718 under different lubrication conditions. Optimization of UAG is necessary in identifying the best parameter combination depending on the process capability of a given machine tool. For this, experimentation using Taguchi L18 orthogonal array parameter design and optimization based on Grey Relational Analysis (GRA) have been performed. The optimization has been performed using grinding forces (tangential force, Ft) and average roughness parameter (Ra) as the output parameters. Additionally, regression models have been developed to enable the prediction of response variables. To determine the factor contribution on output response ANOVA table and S N ratio analysis have been performed on the Grey Relational Grade (GRG). The statistical analysis has revealed feed has the maximum impact on Ra and cutting velocity has the least effect. Similarly, for Ft depth of cut has the maximum effect and cutting velocity has minimum effect. Confirmation experiments reveal that the regression models were able to make accurate predictions under the test conditions. [ABSTRACT FROM AUTHOR]

Effect of the HNTs nanotubes together with MWCNTs nanotubes on the IS of PMMA composites compared to PMMA matrix FIGURE 4. Therefore, this research was done to study the effects of incorporating HNTs and MWCNTs into the PMMA denture base, in terms of PMMA properties concerning Vicker's hardness, and impact strength. Effect of the HNTs nanotubes together with MWCNTs nanotubes on VH of PMMA composites compared to PMMA matrix. Figure 7 shows the impact fracture surface of 4.5 wt% HNTs+ 0.5wt% MWCNTs nanotubes filling the PMMA matrix, where the surface was full of sharp ridges and rough cracks propagation, which proves the interaction between the nanotube fillers and PMMA matrix. [Extracted from the article]

Research of material for making hard capsule shell has developed so fast. Commercial capsule shell with gelatin mostly are made from pig skin and makes Muslim people cannot consume drug with capsule preparation. Therefore, more capsule shell material development is needed, raw material which can be substitute gelatin is carrageenan. However, by using carrageenan is still less effective as a drug delivery agent because is easy to crack. With these problems, to improve performance a capsule shell as a drug delivery agent, Spirulina platensis is needed. To optimize both of material between carrageenan and Spirulina platensis, cross linker is used. The purpose of this study was to use CaCl2 as cross linker to combine the bond between two functional groups and decrease solubility both of material in the water so prolongs the dissolution of the drugs to release into the intestine. The formulation of the solution that used in this research is variation of CaCl2 (0.75%; 1%; 3%; 5%, 7%) (w/v). The characterization was performed by using water content, pH, water resistance, durability in acid solution test and this parameter follow Department of Health Republic of Indonesia. The best concentration of CaCl2 which used in this research is 7% (w/v), with characterization that obtained as follows: water content is 13.52%, resistance in water in 38'09", resistance in acid environment in 44'54", and pH is 6.4. This capsule is able to survive in acid condition at pH 1.2 for 75 minutes, with release the drug as much as 61.30%, and then at pH 4.5 release the drug of 54.90%, and pH 6.8 release the drug of 89.58%. The CaCl2 concentration affected to porosity of capsule shell and drug release from inside capsule shell, besides that CaCl2 also effect the absorption ability of capsule shell. By paying attention to these parameters, it is expected that the capsule formed will have strong structural and not easy to dissolution in the water and acid environment, so that the drug will be released according to the destination organ. [ABSTRACT FROM AUTHOR]

Wire cut EDM is a non-traditional machining process, is used to machine hard materials. Wire electrode is one of the main factors that evaluate the performance of wire EDM which develops a vast performance. In this work, hard materials like Inconel and Titanium alloys are to be cut with combination of different parameters using a Brass electrode and their surface quality, Metal removal rate (MRR) will be analysed. The outcomes of various parameters such as pulse ON time, pulse OFF time and wire tension are the input parameters on surface quality to be studied. The results were observed that there was an increase in Metal removal rate with increase in pulse ON time and Input power and with the increase in pulse OFF time the Metal removal rate value decreases gradually. It has been found that surface roughness is reduced with enhance in pulse OFF time. Enormous concern has to be taken in constructing equally. [ABSTRACT FROM AUTHOR]

We demonstrate the capabilities of ion-beam lithography (IBL) for the manufacturing of the X-ray refractive micro-optics. With the help of IBL, the hardest of current materials - diamond - was milled, and microscale diamond lenses were produced. Lenses have a rotationally parabolic profile with radii of parabola apexes less than 5 µm. As has been confirmed with SEM and AFM, shape profile errors of fabricated lenses were<200 nm, while the surface roughness was estimated to be 50 nm. Single lenses were stacked in the CRL within one technological process with high alignment precision. [ABSTRACT FROM AUTHOR]

Machining of hard materials has a vital role in production industries. An attempt has been made to compare the machinability aspects of as-received and microwave irradiated coated carbide inserts on turning AISI 4340 steel (EN-24). Chemical Vapour Deposition carbide inserts were subjected to microwave heat treatment at 1000 °C and machining studies were conducted on AISI 4340 steel. The main concern of this work is to increase the tool life and the hardness of inserts. The experimental work revealed that the tool wear (W) is less dominant on microwave heat treated tool. The obtained result reveals that slightly increase the hardness of tool inserts after microwave heat treatment process. Micro-hardness of both as-received and microwave irradiated inserts was evaluated using Vicker's micro hardness tester. The cutting edges of tool insert were examined by Optical Measuring Microscope. Chip formation is analyzed at various cutting speeds, feed rates, depth of cuts and machining time. [ABSTRACT FROM AUTHOR]

Automobile Water Pump shaft Failures usually occurs, Replace of Automobile Water Pump do occur often and the cause for such replacements tends to be none other the failure of the component. Shaft pump were made of mild steel, this study focuses on characterize of the shaft used in the pump system, determine methods to improve the corrosion resistance and wear resistance of the pump and recommend a hard coating material to improved performance of Automobile Water Pump. Hard chromium coating technique is used to extend the service life of water pump and improving the resistance of wear and corrosion. Wear test was carried out on Pin on Disc D2625-83 at room temperature of hard samples coating and shaft pump substrate without coating, all hard samples coating has smaller values of wear rate comparative without coating . Corrosion testing was done on cyclic Potentiostat of hard chromium coated samples and comparison substrate material, the hard Cr coating shows lower corrosion rate as compare to steel shaft substrate also hardness increased with hard chromium coating on the substrate. [ABSTRACT FROM AUTHOR]

In the last few years Manufacturing industries are forced to produce a product in minimum time as well as with maintained quality standards, high precision so that they can sustain in the global market competition. This is can be achieved by regulating the process parameters so that desired output can be achieved. Input parameters plays an important role to achieve the better surface quality and MRR. Amongst all Non-traditional machining processes EDM is most popular machining process which is capable to machine hard materials like alloys and composites. In last decades development in ceramic matrix composites have made some new research scopes in the EDM. In this paper literature review of various modern optimization techniques in EDM is presented. New modern optimization techniques applied and relevant measures that influence the result of the EDM process are considered under main objective. The review period is considered from 2008 to 2018. This study has been classified according to different EDM assisted process such as Die-sinking EDM, PMEDM (Powder Mixed-EDM), Micro-EDM and WEDM. In earlier review work on such large scale was not attempted by considering all the EDM assisted processes at a time. This research work can be helpful for researchers to better understanding about modern optimization techniques in EDM and help them to decide their research direction. [ABSTRACT FROM AUTHOR]

Ti-6Al-4V is the most popular type of titanium alloy having a combination of high strength to weight ratio, light weight, high strength at elevated temperature, good corrosion resistance, and good biocompatibility properties. Aerospace, automotive, oil and gas, and biomedical industries, all gained benefits from this material due to its inherent properties. However, Ti-6Al-4V is considered as hard to machine material and is known for its poor machinability mostly due to its own good combination of properties. This has attracted interest in many researchers to study the outcome of different machining conditions and environments on the machining performance of Ti-6Al-4V. A lot of efforts has been put to increase the productivity in machining Ti-6Al-4V by exploring the possibility of high speed machining and the effects of various cooling strategy. This paper presents a review on the application of cold air and nano MQL as one of the cooling strategies in high speed milling of Ti-6Al-4V. [ABSTRACT FROM AUTHOR]

Wire Electrical Discharge Machining (Wire-EDM) is a sophisticated machining process to machine harder conductive materials with greater accuracy and precision. This research aims to find the optimal parameter for machining of AISI D3 steel which is also referred to as High Carbon High Chromium steel (HCHCr). The experiments are carried out with pulse-on time, pulse-off time, current and voltage as input variables. Two different thickness of work material 50 mm and 75 mm were machined using demineralized water with and without copper powder as dielectric medium. The effect of demineralized water with and without copper powder on the response variables such as material removal rate (MRR) and surface roughness (Rq) were studied in detail. The experiments were conducted on Taguchi’s L18 orthogonal array (OA). Analysis of the obtained experimental data are carried out using Minitab 16. Signal-to-Noise ratio are derived. Besides Taguchi optimization technique, combined objective function (Minimization) is adopted to find the common optimal input parameter. This research makes an ardent attempt to conclude that the demineralized water with copper powder when used as dielectric gives higher MRR and balanced Rq and optimum parameters for 50 mm and for 75 mm workpiece are reported. [ABSTRACT FROM AUTHOR]

Within the Collaborative Research Centre 1153 “Tailored Forming“ a process chain for the manufacturing of hybrid high performance components is developed. Exemplary process steps consist of deposit welding of high performance steel on low-cost steel, pre-shaping by cross-wedge rolling and finishing by milling. Hard material coatings such as Stellite 6 or Delcrome 253 are used as wear or corrosion protection coatings in industrial applications. Scientists of the Institute of Material Science welded these hard material alloys onto a base material, in this case C22.8, to create a hybrid workpiece. Scientists of the Institut für Integrierte Produktion Hannover have shown that these hybrid workpieces can be formed without defects (e.g. detachment of the coating) by cross-wedge rolling. After forming, the properties of the coatings are retained or in some cases even improved (e.g. the transition zone between base material and coating). By adjustments in the welding process, it was possible to apply the 100Cr6 rolling bearing steel, as of now declared as non-weldable, on the low-cost steel C22.8. 100Cr6 was formed afterwards in its hybrid bonding state with C22.8 by cross-wedge rolling, thus a component-integrated bearing seat was produced. Even after welding and forming, the rolling bearing steel coating could still be quench-hardened to a hardness of over 60 HRC. This paper shows the potential of forming hybrid billets to tailored parts. Since industrially available standard materials can be used for hard material coatings by this approach, even though they are not weldable by conventional methods, it is not necessary to use expensive, for welding designed materials to implement a hybrid component concept. [ABSTRACT FROM AUTHOR]

Accumulative roll bonding (ARB) is one of the severe plastic deformation methods of producing ultrafine grained laminated metal composites (LMCs). This paper is focused on LMCs consisting of dissimilar bimetal system of aluminum alloys AA1050/AA6061. One difficulty of roll bonding two dissimilar materials is obtaining of elevated strain at the interface of the composite in order to provide the ultrafine grain structure and superior bonding strength between the stacked layers. Compared to conventional ARB the asymmetric accumulative roll bonding is more appropriate for the production of dissimilar bimetal composites. This paper presents the results of the finite element simulation and comparison of interface shear strain behavior during symmetric and asymmetric ARB of AA1050/AA6061 bimetal composites. Influence of rolls speed ratio, contact friction and layer thicknesses on strain distribution through composite thickness, especially on interface between the AA1050 and AA6061 layers, during asymmetric ARB were analyzed by FEM in details. It was numerically shown that the strain in soft material (AA1050) of the interface can be extremely increased while the strain in hard material (AA6061) remains almost unchanged. Since the strain at the interface can be seriously increased, then the ultrafine grain size and the superior bonding strength between the stacked layers are expected during asymmetric ARB. The FEM results of investigation of the influence of the rolls speed ratio and friction conditions on strain distribution through composite thickness, especially on interface between the AA1050 and AA6061 layers, can be useful for the development of the improved ARB process of AA1050/AA6061 bimetal composites with UFG structure and high bond strength. [ABSTRACT FROM AUTHOR]

In these days of nanotechnology the materials like BN is of utmost importance as in hexagonal phase it is among hardest materials. The phonon mode study of the materials is most important factor to find structural and thermodynamcal properties. To study the phonons de launey angular force (DAF) constant model is best suited as it involves many particle interactions. Therefore in this presentation we have studied the lattice dynamical properties and specific heat of BN in wurtzite phase using DAF model. The obtained results are in excellent agreement with existing results. [ABSTRACT FROM AUTHOR]

The resistance of low carbon steel pipes API 5L GR.B as welded joints to sulphide stress cracking SSC was tested using NACE Standard test method TM 0177_ Method (C). Two stress levels of the material's yield strength were applied, 75 % sy and 100 % sy in three different conditions; as received, as welded, and stress relieved samples. Total of seventeen samples were tested; two as received samples without any welding process, six samples as heat treated, and nine samples as welded. The effect of hardness level on material's susceptibility to sulphide stress cracking was examined. Raw Natural Gas was used as a source of Hydrogen Sulphide (H2S) in the test, which represents the real environment that the material was exposed to. Results show that samples with high hardness (higher than 22 HRC) were failed the test which was expected as in the NACE Standard MR175. Samples with low hardness (lower than 22 HRC) were passed the test which was expected as in the NACE Standard MR175. The received samples of low hardness failed the test which was not expected. [ABSTRACT FROM AUTHOR]

The probability of detection (POD) of inspection techniques is a key input to estimating the lives of structural components such as aircraft engines. This paper describes work conducted as a part of the development of POD curves for the ultrasonic detection of synthetic hard alpha (SHA) inclusions in titanium aircraft engine forgings. The sample upon which the POD curves are to be based contains four types of right circular SHAs that have been embedded in a representative titanium forging, as well as a number of flat bottomed holes (FBHs). The SHAs were of two sizes, [sharp/mesh/hash_synonym]3 and [sharp/mesh/hash_synonym]5, with each size including seeds with nominal nitrogen concentrations of both 3 and 17 wt. %. The FBHs included sizes of [sharp/mesh/hash_synonym]1, [sharp/mesh/hash_synonym]3, and [sharp/mesh/hash_synonym]5. This discreteness of the data poses a number of challenges to standard processes for determining POD. For example, at each concentration of nitrogen, there are only two sizes, with 10 inspection opportunities each. Fully empirical, standard methodologies such as a versus a provide less than an ideal framework for such an analysis. For example, there is no way to describe the beam limiting effect whereby the signal no longer increases the flaw grows larger than the beam, one can only determine POD at the two concentration levels present in the block, and confidence bounds tend to be broad because of the limited data available for each case. In this paper, we will describe strategies involving the use of physics-based models to overcome these difficulties by allowing the data from all reflectors to be analyzed by a single statistical model. Included will be a discussion of the development of the physics-based model, its comparison to the experimental data (obtained at multiple sites with multiple operators) and its implications regarding the statistical analysis, whose details will be given in a separate article by Li et al. in this volume. [ABSTRACT FROM AUTHOR]

The sintering behavior of yttria-stabilized zirconia, with the influence of small additions of MnO2 (up to 1 wt %) sintered over the temperature range from 1250° C to 1500° C was investigated. It was found that the mechanical properties of Y-TZP were dependent on the dopant amount and sintering temperature. The results revealed that relative densities above 97.5% of theoretical (i.e. >5.95 Mgm-3) could be obtained in Y-TZPs sintered at low temperatures, 1250° C and 1300° C, with the additions of ≤0.3 wt% MnO2. In comparison to the undoped samples, the additions of up to 1 wt% MnO2 and for sintering up to 1350° C was found to be beneficial in enhancing the Vickers hardness of the ceramic. The fracture toughness of Y-TZP however, was found to increase only in the 1 wt% MnO2-doped samples when sintered above 1400° C. The relation between the measured mechanical properties is discussed with the emphasis on the role of the manganese oxide. [ABSTRACT FROM AUTHOR]

Perfectly hard particles are those which experience an infinite repulsive force when they overlap, and no force when they do not overlap. In the hard-particle model, the only static state is the isostatic state where the forces between particles are statically determinate. In the flowing state, the interactions between particles are instantaneous because the time of contact approaches zero in the limit of infinite particle stiffness. Here, we discuss the development of a hard particle model for a realistic granular flow down an inclined plane, and examine its utility for predicting the salient features both qualitatively and quantitatively. We first discuss Discrete Element simulations, that even very dense flows of sand or glass beads with volume fraction between 0.5 and 0.58 are in the rapid flow regime, due to the very high particle stiffness. An important length scale in the shear flow of inelastic particles is the ‘conduction length’ δ = (d/(1-e2)1/2), where d is the particle diameter and e is the coefficient of restitution. When the macroscopic scale h (height of the flowing layer) is larger than the conduction length, the rates of shear production and inelastic dissipation are nearly equal in the bulk of the flow, while the rate of conduction of energy is O((δ/h)2) smaller than the rate of dissipation of energy. Energy conduction is important in boundary layers of thickness δ at the top and bottom. The flow in the boundary layer at the top and bottom is examined using asymptotic analysis. We derive an exact relationship showing that the a boundary layer solution exists only if the volume fraction in the bulk decreases as the angle of inclination is increased. In the opposite case, where the volume fraction increases as the angle of inclination is increased, there is no boundary layer solution. The boundary layer theory also provides us with a way of understanding the cessation of flow when at a given angle of inclination when the height of the layer is decreased below a value hstop, which is a function of the angle of inclination. There is dissipation of energy due to particle collisions in the flow as well as due to particle collisions with the base, and the fraction of energy dissipation in the base increases as the thickness decreases. When the shear production in the flow cannot compensate for the additional energy drawn out of the flow due to the wall collisions, the temperature decreases to zero and the flow stops. Scaling relations can be derived for hstop as a function of angle of inclination. [ABSTRACT FROM AUTHOR]

The NASA Stardust mission to comet 81P/Wild 2 collected grains of cometary dust freshly ejected from the comet during a fly-by at a speed of 6.1 km s-1. These were captured on aluminum foils and in blocks of silica aerogel. The dust underwent a severe shock during capture. The nature of the shock process depends on the properties of the dust and the collecting media. On the aluminium, the shock process and impact damage is typical of that between high-density (or hard materials) at high velocity, resulting in craters lined with impactor residues. The peak shock pressures are estimated at 60–80 GPa. Two main crater types are seen, simple bowl shaped and multiple pit craters: these reflect the degree of consolidation of the original dust grain. Capture in the low density aerogel was via a more gradual slowing of the dust grains accompanied by a variety of effects on the grains (complete break up of weak grains vs. ablation of well consolidated grains). The relation between the structure of the dust grains and the resulting impact features in both collector materials is discussed. [ABSTRACT FROM AUTHOR]

Through the measurement of Hugoniot parameters, we can get useful information about high-pressure phase transitions, equations of state (EOS), etc. of solids, without pressure calibration. We have performed the Hugoniot measurement experiments on various kinds of hard materials including chalcogenides, oxides, nitrides, and borides by using a high time-resolution streak photographic system (inclined-mirror method). It was found that almost all brittle materials behave as an elasto-isotropic solid which loses shear strength much above the HEL, unlike metals (elasto-plastic solid), except TiB2. The phase transitions have been observed for ZnS, ZnSe, TiO2, ZrO2, Gd3Ga5O12, AlN, B4C, etc. Some oxide materials showed virtually incompressible EOS's in the high-pressure phase region. Here, the Hugoniot compression data are reviewed, and the yield property and phase transitions of these hard materials are discussed, as well as the EOS of the high-pressure phase. [ABSTRACT FROM AUTHOR]

Recent developments in plasma synthesis of hard materials using energetic ions are described. Metal Plasma Immersion Ion Implantation and Deposition (MePIIID) has been used to prepare several hard films: from diamondlike carbon (DLC) to carbides, from nitrides to oxides. The energy of the depositing species is controlled to maximize adhesion as well as to change the physical and chemical properties of the films. Adhesion is promoted by the creation of a graded interface between the film and the substrate. The energy of the depositing ions is also used to modify and control the intrinsic stresses and the microstructure of the films. The deposition is carried out at room temperature, which is important for temperature sensitive substrates. A correlation between intrinsic stresses and the energetics of the deposition is presented for the case of DLC films, and means to reduce stress levels are discussed. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]