Electrolytic In-process Dressing (ELID) Grinding

Day by day increasing the demand of precision ophthalmic surgical knife all over the world. Ophthalmic surgical knives are crucial tools in various eye procedures, including cataract surgery and other visioncorrecting surgeries. Diamond grinding wheel is used for removing excess material and consistency the final shape and sharpness of the ophthalmic surgical blades. Dressing of diamond grinding wheels becomes necessary after 300-350 times of knife production to remove worn grain, maintain wheel profile, and ensure a sharp cutting surface for precise grinding operation. This research work focuses on the design and manufacturing of a specialized holding device for diamond wheel dressers, aiming to enhance the efficiency and precision of grinding processes. The proposed device provides a stable platform for securing diamond wheel dressers during the dressing operation, optimizing the truing and shaping of grinding wheels. By improving the stability and repeatability of diamond wheel dressing, this holding device contributes to enhanced surface finish and dimensional accuracy in machined workpieces.

List of Figures xv List of Tables xviii Chapter 1. Introduction 5.4.2 Influence of in-process dressing conditions on surface roughness and tool wear 5.4.3 The surface defects and the ELID parameter 5.5 The effect of the grinding parameters 5.5.1 Effect of feed rate on ELID grinding 5.5.2 The effect of the feed rate and current duty ratio on the ELID grinding 5.6 Concluding remarks Chapter 6. Wear mechanism of the ELID-grinding wheels 6.1 Introduction 6.2 The character of the ELID-grinding wheels 6.3 Wear mechanisms of the ELID-grinding wheels 6.3.1 Wear during pre-dressing vi 6.3.2 Wear mechanism during in-process dressing 6.4 Wear reduction strategies 6.5 Influence of grinding parameters on wheel-wear 6.5.1 Horizontal slots 6.5.2 Vertical grooves 6.5.3 Surface grinding 6.6 Model for the in-process dressing 6.7 Concluding remarks Chapter 7. Investigations on the ELID-layer 7.1. Introduction 7.2 Analysis on the pre-dressed wheel 7.3 Microconstituents of the ELID layer 7.4 Analysis on the ELID-layer 7.5 Investigation of the mechanical properties of the ELID layer 7.5.1 Principle of nanoindentation 7.6 Grit size and the anodized wheels 7.7 Advantages of grinding with anodized ELID layer 7.7.1 The profile of the grinding wheel 7.7.2 Control the wear rate of ELID-layer (Effect of pulse ON-time and OFF-time) 7.8 Concluding remarks Chapter 8. Modeling of micro/nanoELID grinding 8.1 Introduction vii 8.2 Principle and modeling of micro/nanoELID grinding 8.2.1 Modeling of the work surface 8.2.2 Modeling of the ELID-grinding wheel surface 8.2.3 Modeling the contact between the asperities 8.2.4 Estimation of the real area of contact 8.2.5 The development of force model for micro/nanoELID grinding 8.2.5.1 Force per grit model 8.2.5.2 Normal and tangential grinding forces 8.3 Simulation and verification of the model 8.3.1 Selection of grinding method, grinding parameters and dressing parameters 8.3.2 Simulation of the actual contact area and the grit density 8.3.3 Simulation and verification of the grinding forces 8.4 Concluding remarks Chapter 9. Conclusions, contributions and recommendations 9.1 Conclusions 9.1.1 The grinding forces 9.1.2 The surface finish 9.1.3 The wheel wear 9.1.4 ELID-layer (oxidized layer) 9.1.5 Conclusion obtained from the developed grinding model 9.2 The research contributions 9.2.1 The approaches and analyses on ELID grinding 9.2.2 Proposal of new grinding model 9.3 Recommendations for Future research viii References 146 List of publications from this study 151 Appendices Appendix A Tables A-1 Appendix B Fick's law of diffusion B-1 Appendix C Simulated results C-1 which may be difficult to produce using the existing conventional processes. Automobile and aeronautic industries use ceramics for producing components such as automobile engine parts and turbine blades, which also find difficult to manufacture using the conventional methods [Blaedel et al., 1999]. Grinding is a versatile finishing process which is normally used for finishing components up to a surface roughness of few micrometers. However, it is possible to enough grain protrusion. In some grinding wheels such as cast iron-bonded wheels, a protective layer is formed on the grinding wheel during electrolysis and it resists the current flow. So, the conductivity of the grinding wheel is reduced after every dressing due to the oxidized layer deposition, which also prevents the bonding material from further oxidization. The grinding wheels that can produce such a protective layer during electrolysis are more suitable for in-process dressing. This thesis consists of nine chapters. Chapter 1 gives an introduction to the work done in this research. In chapter 2, the literature review of the ELID techniques, principles of the ELID, different techniques and the applications of the ELID are presented. Chapter 3 explains the basic principle and the classifications of the ELID. The principle of the electrolysis, the basic components of the ELID, classification and the mechanism of the ELID are described. The description of experimental setup, grinding experiments, measuring equipments and the measuring techniques have been explained in Chapter 4.

Grinding is often the final step in the process/manufacturing chain, meaning that no subsequent postgrinding correction of the surface and geometry is performed. This imposes strong requirements on grinding-machine technology and on the understanding of this finalising process. While grinding has unique capabilities it is nevertheless in competition with other machining processes. The evolution of grinding machines is driven by process requirements like accuracy, MRR, and subsurface integrity. The regeneration of the tool on the machine with dressing devices is to be regarded as unique for grinding machines, hence a grinding machine always runs two separate processes. The high accuracy of grinding has, in fact, been an obstacle to simply adopting developments from other machining processes. Also, a lack of experienced machinists and a general trend towards individualized products and one-piece flow has required a transition from an experience-based approach to a science-based approach. Development is further driven by market demands, such as cost-reduction in terms of CAPEX, footprint, TCO versus quality, and throughput, which affect business models and the machine's design and construction. Moreover, the current mega-trendssuch as resource efficiency, individualization, ergonomics and Industry 4.0are changing the appearance of grinding machines, which is also affected by the availability of new technologies, especially sensors, actuators and the control or machine intelligence. This paper reviews the most-relevant technologies, assesses their impact and the readiness of industry to adopt them, identifies the still-open issues, and concludes with future research requirements.

The demand for Silicon Carbide ceramics has increased significantly in the last decade due to its reliable physical and chemical properties. Sometimes, single side grinding for ceramics is preferable over surface grinding, because single side grinding has the ability to produce flat surfaces. However, the manufacturing cost is still high because of the high tool wear and long machining time. Additionally, most of these grinding processes are followed by a lapping process. One of the ways to address the high costs is to eliminate the final lapping process by the use of electrolysis in process dressing technique (ELID). Part of the solution also entails investigating the influence of different variables on the material removal rate and workpiece surface finish. This paper presents the influence of different grain size on the roughness. Also, the paper presents first a small introduction to fundamentals of ELID. The aim of the paper is to analyze the influence of the grit size upon the surface roughness. In order to do this, a full factorial experiment was designed. Based on the experimental results, a module was developed for each grit size (wheel) on three levels of each variable: the spindle and wheel speed, the applied load and the eccentricity of the workpiece holder.

Ceramics is one of the primary fields in which improvements in processing and advanced products can be anticipated. Such products have an increased technological knowledge content and have to be manufactured using processing technology that is more advanced and better controlled. Advancements in ceramic machining and manufacturing technology are necessary for the commercialization of new processing technology; these innovations may lead to eliminating expensive steps, improving productivity, and increasing product reliability. Most of the industrialized countries of the world have invested heavily in the manufacturing (processing) of new ceramic materials, which led to the production of lower-priced ceramics with better properties. This successful development is useful, but is not good enough for the anticipated boom in the ceramic materials industry. The main problem in the use of ceramics is that machining is still very expensive. This prohibits the replacement of metal parts with ceramic parts in nearly all industries in which machined parts are used, such as the automotive, aerospace, and semiconductor industries. This book presents the latest developments in machining of advanced ceramics. Most of the authors have dedicated their whole lives to the study of ceramic machining and ceramic stock removal mechanisms. Ductile grinding of ceramics is the focus of Chapter 1 by Professor Eda of Ibaraki University in Japan. His laboratory is well known mainly for new methods and tools for machining of ceramics and other semiconductor materials. Chapter 2 comes from Kumamoto University. Over the years, Professors Yasui and Matsuo developed special techniques for grinding fine ceramics using diamond wheels with coarse grains. Chapter 3 deals with fundamentals: mechanisms for grinding of ceramics. Professor Malkin, considered a ''guru'' in grinding of ceramics and general grinding, spent many years investigating different aspects of the grinding of ceramics. This chapter is a kind of summary of his findings. Chapter 4 focuses on the correlation between grinding parameters and the strength and depth of mechanical damage. Professor Mayer of the University of Texas spent most of his life investigating these phenomena. Chapter 5, Chapter 6, Chapter 9, and Chapter 15 present a new technology: electrolytic in-process dressing (ELID) grinding of ceramics, which was developed in Japan by Professor Nakagawa and his student Dr. Ohmori, who is coauthor of three of the chapters dedicated to ELID technologies. The other authors spent long periods of time working with Dr. Ohmori and his team at the Japan Institute for Physical and Chemical Research (RIKEN) in Tokyo. ELID is one of the most promising technologies for machining of ceramics, especially for high accuracy and mirror-like surfaces. I would like to mention three very young coauthors of these chapters: Dr. Katahira, Dr. Kato, and Dr. Spanu, who finished his doctoral thesis on this subject two years ago. The authors of this chapter represent three generations of researchers working on this promising technology. Chapter 7 was written by a team from the Precision Micro-Machining Center of the University of Toledo, Ohio. The chapter presents a method that is new and not very familiar to the industry: belt centerless grinding of ceramics materials using special diamond belts. This method is used mainly for high-efficiency grinding applications where the main objective is the stock removal rate and the second objective is the quality of the surface. Chapter 8 also comes from the Precision Micro-Machining Center and presents a modern technique for monitoring the ceramic lapping process: acoustic emission (AE). AE is well known as a tool to monitor the ceramic grinding process; however, there are only a few studies regarding AE in the lapping process. Chapter 10 was written by a team of academic and industrial researchers: Mariana Pruteanu, Ion Benea, and myself. The chapter presents a study dealing with the lapping of ceramics with diamond slurry and it emphasizes the differences between mono-and polycrystalline diamond. Chapter 11 is one of the chapters with emphasis on fundamentals and presents an original model for lapping of ceramics: the double fracture model. I developed this model with my students over the past fifteen years, trying to provide a more complex material removal model in the case of lapping of ceramics (indentation and scratch). Chapter 12 looks at a method to replace lapping (double lapping) of ceramics with grinding (double grinding) using the same kinematics. Written by Dr. Christian Spanu, Dr. Mike Hitchiner, and myself, this chapter discusses the state of the art for this technology, which is gaining more ground every day. Chapter 13 focuses on the nanomachining of ceramic materials, mainly through super polishing, a technology developed in principle for the semiconductor industry. The work was done at the Precision Micro-Machining Center and uses a state-of-the-art super-polishing machine with a special technology for AlTiC magnetic heads. The quality of the surface obtained is at the level of 2-5 Å. Chapter 14 discusses a new technology that has never been used in industry: laser-assisted grinding of ceramics. I developed this technology with Dr. Howes and Dr. Webster at the University of Connecticut in the early 1990s. New developments show that this is a promising technology, which may allow grinding of ceramics with high productivity and high accuracy at the same time. Chapter 16 and Chapter 17 come from the Fraunhofer Institute of Berlin, one of the best machining laboratories in Germany, with an old tradition in machining of ceramics. Developed by senior Professor Spur and his successor, Professor Uhlmann, one chapter is dedicated to the ultrasonic grinding of ceramics, a technology successfully developed in Berlin; the second is a summary of the findings of the latest research in different grinding methods of ceramic materials. This book is addressed to a broad category of people: engineers and technicians in industry; students; and researchers and scientists in government research institutions. With new alternative fuels and energy on the horizon, ceramic materials are feasible alternative engine materials, able to work at high temperature with minimum wear. I would like to thank all my coauthors and contributors for taking the time to prepare the manuscript. I would also like to thank my wife Jocelyn for putting up with my long hours of work and with very short weekends. Without their help and encouragement, this book would not have been possible.

Based on an extensive review of traditional machining technologies, a novel method to manufacture abrasive tools using ultraviolet (UV) light curing technique was proposed to achieve the economy and accuracy for machining ceramic materials. The UV cured resin bond tools have been proven to have substantial advantages in machining performance. However, there has been limited research on the abrasion mechanism of such tools. In this paper, the mechanism of such resin bond tools is proposed as a hybrid of conventional grinding and lapping, and called as a grinding/lapping (G/L) process. In order to verify the proposed mechanism, three resin bond diamond wheels cured by UV light were used to conduct lapping, grinding, and G/L process, respectively, under the same experimental setup. The experimental results like surface roughness (RA) and surface profiles of the workpieces undertaking the three operations were compared and showed good agreement with the proposed mechanism.

Laser ablation is a novel non-mechanical wheel preparation method for optimizing the treatment costs of superabrasive tools. In this study, the thermal e ects of picosecond laser radiation on vitri ed and resin bond CBN superabrasive grinding wheel surfaces were analytically and experimentally investigated. The analytical approach was intended to nd threshold process parameters for selective ablation of cutting grains and bond material. A picosecond Yb:YAG laser device was integrated with a cylindrical grinding machine, which facilitated the treatment of grinding wheel as it was mounted on the grinding spindle. It is shown that the extent of material ablation is de ned by the maximum surface temperature induced by the laser radiation, which is in turn de ned by the laser pulse energy. It is also suggested that the depth of laser thermal e ects is governed by the relative speed of the laser scanner with respect to the wheel surface.

In this paper a new and innovative method for the patterning of grinding wheels is presented. The patterns are machined with a patterning tool by using fly-cutting kinematics. By changing the patterning process parameters different pattern sizes and densities can be machined in a flexible way. Surface and cylindrical grinding experiments show that grinding with patterned grinding wheels can significantly reduce process forces, grinding burn and grinding power. The surface roughness increases because less active cutting edges remain when grinding with patterned wheels. But especially for roughing processes the results show great potential for increasing the overall grinding performance.

The functions of the passivating film, the factors influencing the thickness and compactness of the film and the control strategies of the film state in Electrolytic In-process Dressing (ELID) precision grinding were analysed. The loop current, which can characterise the film state was monitored and the experiments of the ELID grinding were conducted in the active controlling of the film state.

Abrasive machining is an often employed finishing process for different materials such as metals, ceramics, glass, rocks, etc. with which close tolerances and good dimensional accuracy can be achieved. Grinding wheels are considered to be the key product for abrasive machining in this era of advanced manufacturing processes. High material removal rate and enhanced finishing can be obtained with it if combined with raw and finishing machining. In this present paper we are going to review such high abrasive efficiency grinding wheels, which have a keen potential to replace the conventional grinding wheels and rejuvenate the technology of grinding. Our paper primarily deals with CBN (Cubic Boron Nitride) grinding wheels with the purpose of identifying the state of art in grinding machining and serving for the future researches.

This paper reports the development of an ultra-precise grinding system based on a new grinding technique called the "Arc Envelope Grinding Method (AEGM)". AEGM, which is used for grinding aspheric ceramic mirrors, increases both wheel life and grinding performance, and significantly decreases total production costs. The necessary instrumentation and control system of our new instrument that utilizes AEGM have been designed and built. The tool path was calculated on a supercomputer, and the CNC program generation and tool path compensation were performed on a PC linked to the same supercomputer. Using this grinding system, aspheric mirrors of glass and silicon carbide, 100 mm in diameter, were successfully ground. The form error after the first grinding (without any compensation) was less than 1.8 um, and the roughness was R,, = 82 nm (R, = 10 nm).

In machining processes, grinding is often chosen as the final machining method. Grinding is often chosen as the final machining method. This process has many advantages such as high precision and low surface roughness. It depends on many parameters including grinding parameters, dressing parameters and lubrication conditions. In grinding, the surface roughness of a workpiece has a significant influence on quality of the part. This paper presents a study of the grinding surface roughness predictions of workpieces. Based on the previous studies, the study built a relationship between the abrasive grain tip radius and the Standard marking systems of the grinding wheel for conventional and superabrasive grinding wheels (diamond and CBN abrasive). Based on this, the grinding surface roughness was predicted. The proposed model was verified by comparing the predicted and experimental results. Appling the research results, the surface roughness when grinding three types of steel D3, A295M a...

The demand for Silicon Carbide ceramics has increased significantly in the last decade due to its reliable physical and chemical properties. Sometimes, single side grinding for ceramics is preferable over surface grinding, because single side grinding has the ability to produce flat surfaces. However, the manufacturing cost is still high because of the high tool wear and long machining time. Additionally, most of these grinding processes are followed by a lapping process. One of the ways to address the high costs is to eliminate the final lapping process by the use of electrolysis in process dressing technique (ELID). Part of the solution also entails investigating the influence of different variables on the material removal rate and workpiece surface finish. This paper presents the influence of different grain size on the roughness. Also, the paper presents first a small introduction to fundamentals of ELID. The aim of the paper is to analyze the influence of the grit size upon the...

The efficient processing of innovative materials, the further development of grinding tools and machine concepts as well as an increasing economic and environmental pressure are current challenges in grinding technology. High Performance Grinding processes offer a huge potential to overcome these challenges and increase productivity. They are characterized by a significant increase in material removal rate and component quality plus a reduced need of resources. In this paper, possibilities are presented and discussed for extending the process boundaries of conventional grinding processes in order to create High Performance Grinding processes. Based on current research, potentials to increase productivity of conventional grinding processes are described. In addition to process-specific optimization of the machine and the grinding tools, opportunities are pointed out for the numerical prediction of the process boundaries as well as methods for mathematical interpretation and analysis of grinding wheel structures and topographies. Moreover, opportunities are presented for future increases in productivity by combining High Performance Grinding processes with other manufacturing technologies.

This research proposes a new application of 3-axis CNC milling machine for polishing the 60 HRC hardness steels. The rotary polishing tools are designed by refer to the end-mill ball nose’s design. The diamond powder are coated in rotary polishing tools by resinoid bonding method and concentrated in 4.4 karat/cm2. The Zig-milling tool paths are used to polish the hardness steel. After polishing, the confocal laser scanning microscope is used to analyze the arithmetic mean surface roughness of the hardness steels. The L12 orthogonal array of the Taguchi’s method is selected to conduct the matrix experiment to determine the optimal polishing process parameters. The diamond grit size and cutting speed of the rotary polishing tools, feed rate and step over of the tool path, the depth of polishing process penetration, and polishing time are used to study. The combination of the optimal level for each factor of the hardness steel polishing process are used to study again in the confirmati...

Most of the machine parts can be created by any one of the various manufacturing methods such as forging, machining, casting or welding methods. Choice of the manufacturing method depends on production costs of the alternatives for individual parts. Turning, grinding, lapping, etc. are the most common surface machining processes commonly employed in all manufacturing units to develop the components having high quality. The main aim of this project is to design and fabricate a suitable attachment for cylindrical grinding machine to turn cylindrical rods. It reduces the machining time to grinding cylindrical rods in cylindrical grinding machine to. This attachment is very economical when compared to all other attachments that are used to turn and grind at same place/simultaneously.

In this paper, the electronic speckle pattern interferometry (ESPI) and the finite element method (FEM) were used to obtain the thermal deformation induced in a centrally supported thermoelectric cooler (TEC). The results of ESPI and FEM are in good agreement and show that the warpage varies linearly with respect to the temperature difference between the two ceramic plates inside the TEC.

The demand for Silicon Carbide ceramics has increased significantly in the last decade due to its reliable physical and chemical properties. Sometimes, single side grinding for ceramics is preferable over surface grinding, because single side grinding has the ability to produce flat surfaces. However, the manufacturing cost is still high because of the high tool wear and long machining time. Additionally, most of these grinding processes are followed by a lapping process. One of the ways to address the high costs is to eliminate the final lapping process by the use of electrolysis in process dressing technique (ELID). Part of the solution also entails investigating the influence of different variables on the material removal rate and workpiece surface finish. This paper presents the influence of different grain size on the roughness. Also, the paper presents first a small introduction to fundamentals of ELID. The aim of the paper is to analyze the influence of the grit size upon the...

Rational exploitation of super hard grinding wheels with metal bond requires estimation of constituent costs of grinding process and dressing of grinding wheels. In the article the method of electrochemical dressing of super hard grinding wheels and economical analysis of electrochemical dressing of these kind of grinding wheels consisted in assessment of selected costs of this process has been presented. Also analysis of costs of the grinding process has been depicted. Obtained relationships allowed us to estimate contribution of respective component of costs of grinding process using super hard grinding wheels and are basis for their optimization.

Cylindrical grinding is very important process to improve quality of the component and to get precision dimensions with smooth surface finish. In the manufacturing sector, producing smooth surface finish plays an important role. To fulfill this smooth finish, surface grinding process is mostly used in which the parameters to be considered are surface quality and metal removal rate. Several factors which include depth of cut, wheel grade, wheel speed, material properties and table speed affects the machining process economics. This paper mainly focuses on developing the empirical models using response surface methodology for surface roughness and metal removal rate by considering control factors as wheel speed, table speed and depth of cut. The main objective of using Response surface methodology (RSM) on surface grinding operation of EN19 steel is to find optimum machining parameters which leads to minimize surface roughness and maximum metal removal rate. For conducting the experim...

The automotive industries leaned toward a decentralized approach since the booming of the products in the last century. The leading among them has the principal mostly in the growth countries and the plant mostly in developed ones. However, there is a technological gap between the principal and the plants. So, the problem arises when some processes could not be in the plant. In order to narrow that gap, the study conducted about the maintenance in the honing process. Honing is one type of finishing to ensure the surface quality of the product. The process categorized into subtractive manufacturing. The distinct characteristic of subtractive manufacturing is the cutting tool. The quality of the tool has to be better than its working piece. In other words, in the case of honing the surface roughness and the form of the tool has to be controlled tightly. In this study, the honing tool was corrected by truing and dressing. Truing and dressing are done simultaneously by grind the honing tool using a cylindrical grinding machine. Parameters dominant in the truing and dressing process are feeding and depth of cut. The processes tried by varying ten feeding value and four depth of cut value. From those parameter variations, the roughness then measured. It infers that the bigger the feeding, the roughness is getting coarser.

This paper outlines the hard machining procedures, their applicability, the increase of their efficiency and the possibilities provided through their combination. It focuses on the advantages of the cutting and grinding compared to each other and also on the cases when it is appropriate to apply them or possibly combine them.

Stvaranje i razdioba topline tijekom obrade odvajanjem cestica jedna je od fenomenoloskih karakteristika tih postupaka, koja znatno utjece na funkcionalnost obrađenih povrsina. Rad se bavi proucavanjem distribucije topline tijekom brusenja nikaljnih legura i njenim utjecajem na kvalitetu brusenih povrsina uslijed pojave napetosti (zaostalih naprezanja). Analiza razdiobe topline temelji se na mjerenju kontaktnih temperatura između brusnog kotaca i obradka te tangencijalne komponente sile rezanja. Razdioba topline tijekom brusenja nikaljnih legura razlicita je od one tijekom brusenja uobicajenih željeznih legura, primjerice celika za kotrljajuce ležajeve, prvenstveno zbog njihove niže toplinske provodnosti. Također, uporaba bor-nitridnih (CBN) i dijamantnih bruseva znacajno smanjuje toplinska opterecenja obradaka, prvenstveno uz uporabu rashladnih fluida. Ta cinjenica znatno utjece na pojavu napetosti nakon brusenja. Rezultati analize pokazuju da postoji povezanost između razdiobe top...

Cylindrical grinding is very important process to improve quality of the component and to get precision dimensions with smooth surface finish. In the manufacturing sector, producing smooth surface finish plays an important role. To fulfill this smooth finish, surface grinding process is mostly used in which the parameters to be considered are surface quality and metal removal rate. Several factors which include depth of cut, wheel grade, wheel speed, material properties and table speed affects the machining process economics. This paper mainly focuses on developing the empirical models using response surface methodology for surface roughness and metal removal rate by considering control factors as wheel speed, table speed and depth of cut. The main objective of using Response surface methodology (RSM) on surface grinding operation of EN19 steel is to find optimum machining parameters which leads to minimize surface roughness and maximum metal removal rate. For conducting the experim...

The selected modifications to the construction of grinding wheels were described which facilitate an increase in the material removal rate (grinding wheels with conic chamfer and grinding wheels with microdiscontinuities on the active surface). Using these background details, a suggested thesis was put forward regarding the need to develop a device which will allow for the shaping of the macrogeometry of the grinding wheel (cylindrical and conical surfaces) and the microdiscontinuities within the dressing operation simultaneously. The device was presented and prepared in two functional variants (horizontal and vertical mounting of the motor), then a prototype was described. An example of the grinding wheel active surface, shaped by using this device, was also presented. The theoretical analysis and experimental verification performed determine that the error of shaping the conic chamfer angle within the range of 0-1.5º, using the developed device, is approximately ±3%.

The automotive industries leaned toward a decentralized approach since the booming of the products in the last century. The leading among them has the principal mostly in the growth countries and the plant mostly in developed ones. However, there is a technological gap between the principal and the plants. So, the problem arises when some processes could not be in the plant. In order to narrow that gap, the study conducted about the maintenance in the honing process. Honing is one type of finishing to ensure the surface quality of the product. The process categorized into subtractive manufacturing. The distinct characteristic of subtractive manufacturing is the cutting tool. The quality of the tool has to be better than its working piece. In other words, in the case of honing the surface roughness and the form of the tool has to be controlled tightly. In this study, the honing tool was corrected by truing and dressing. Truing and dressing are done simultaneously by grind the honing tool using a cylindrical grinding machine. Parameters dominant in the truing and dressing process are feeding and depth of cut. The processes tried by varying ten feeding value and four depth of cut value. From those parameter variations, the roughness then measured. It infers that the bigger the feeding, the roughness is getting coarser.

The paper presents the experimental study conditions and results of M3X60K5VE01-35 monocorundum with vitrified bond grinding wheel wear in 100Cr6 steel peripheral grinding process. The effect of grinding wheel wear on the values of grinding force components as well as surface roughness parameters was analyzed. The grinding wheel wear was determined by profile measurement of the active grinding wheel surface using an inductive sensor. It was shown that the increase in the normal component of the grinding force during the process can be an acceptable criterion for wear of the grinding wheel due to the quasi-linear changes over time.

The rapid wear of diamond dressers in truing and dressing of vitrified CBN wheels remains an unsolved problem, and significantly affects the grinding performance of dressed wheels. Through combining laser-induced thermal effects into the process, laser assisted truing and dressing opened a new avenue for reducing the wear rates of diamond dressers. In this study a systematical investigation on the wear properties of diamond dressers in the novel laser assisted truing and dressing has been conducted, including (1) a theoretical analysis of some underlying items in the process of laser irradiation, (2) an experimental investigation of wear rates in the laser assisted truing and dressing, and (3) influences of the HAZ (heat affected zone) left by the last pass of laser assisted dressing. Experimental results show that the wear ratios of diamond dressers in the laser assisted dressing depend on laser power, depth of cut, and feed rate. Moreover, the heating history also has some impact on the wear ratios of diamond dressers.

The automotive industries leaned toward a decentralized approach since the booming of the products in the last century. The leading among them has the principal mostly in the growth countries and the plant mostly in developed ones. However, there is a technological gap between the principal and the plants. So, the problem arises when some processes could not be in the plant. In order to narrow that gap, the study conducted about the maintenance in the honing process. Honing is one type of finishing to ensure the surface quality of the product. The process categorized into subtractive manufacturing. The distinct characteristic of subtractive manufacturing is the cutting tool. The quality of the tool has to be better than its working piece. In other words, in the case of honing the surface roughness and the form of the tool has to be controlled tightly. In this study, the honing tool was corrected by truing and dressing. Truing and dressing are done simultaneously by grind the honing tool using a cylindrical grinding machine. Parameters dominant in the truing and dressing process are feeding and depth of cut. The processes tried by varying ten feeding value and four depth of cut value. From those parameter variations, the roughness then measured. It infers that the bigger the feeding, the roughness is getting coarser.

Recent developments in grinding have opened up new avenues for finishing of hard and brittle materials with nano-surface finish, high tolerance and accuracy. Grinding with superabrasive wheels is an excellent way to produce ultraprecision surface finish. However, superabrasive diamond grits need higher bonding strength while grinding, which metal-bonded grinding wheels can offer. Truing and dressing of the wheels are major problems and they tend to glaze because of wheel loading. When grinding with superabrasive wheels, wheel loading can be avoided by dressing periodically to obtain continuous grinding. Electrolytic inprocess dressing (ELID) is the most suitable process for dressing metal-bonded grinding wheels during the grinding process. Nano-surface finish can be achieved only when chip removal is done at the atomic level. Recent developments of ductile mode machining of hard and brittle materials show that plastically deformed chip removal minimizes the subsurface damage of the workpiece. When chip deformation takes place in the ductile regime, a defect-free nano-surface is possible and it completely eliminates the polishing process. ELID is one of the processes used for atomic level metal removal and nano-surface finish. However, no proper and detailed studies have been carried out to clarify the fundamental characteristics for making this process a robust one. Consequently, an attempt has been made in this study to understand the fundamental characteristics of ELID grinding and their influence on surface finish.

In this paper a new and innovative method for the patterning of grinding wheels is presented. The patterns are machined with a patterning tool by using fly-cutting kinematics. By changing the patterning process parameters different pattern sizes and densities can be machined in a flexible way. Surface and cylindrical grinding experiments show that grinding with patterned grinding wheels can significantly reduce process forces, grinding burn and grinding power. The surface roughness increases because less active cutting edges remain when grinding with patterned wheels. But especially for roughing processes the results show great potential for increasing the overall grinding performance.

Several machining processes have been created and improved in order to achieve the best results ever accomplished in hard and difficult to machine materials. Some of these abrasive manufacturing processes emerging on the science frontier can be defined as ultra-precision grinding. For finishing flat surfaces, researchers have been putting together the main advantages of traditional abrasive processes such as face grinding with constant pressure, fixed abrasives for twobody removal mechanism, total contact of the part with the tool, and lapping kinematics as well as some specific operations to keep grinding wheel sharpness and form. In the present work, both U d-lap grinding process and its machine tool were studied aiming nanometric finishing on flat metallic surfaces. Such hypothesis was investigated on AISI 420 stainless steel workpieces U d-lap ground with different values of overlap factor on dressing (U d =1, 3, and 5) and grit sizes of conventional grinding wheels (silicon carbide (SiC)=#800, #600, and #300) applying a new machine tool especially designed and built for such finishing. The best results, obtained after 10 min of machining, were average surface roughness (Ra) of 1.92 nm, 1.19-μm flatness deviation of 25.4-mm-diameter workpieces, and mirrored surface finishing. Given the surface quality achieved, the U d-lap grinding process can be included among the ultra-precision abrasive processes and, depending on the application, the chaining steps of grinding, lapping, and polishing can be replaced by the proposed abrasive process.

Over the last century, substantial advances have been made, based on improved understanding of the requirements of grinding processes, machines, control systems, materials, abrasives, wheel preparation, coolants, lubricants, and coolant delivery. This paper reviews a selection of areas in which the application of scientific principles and engineering ingenuity has led to the development of new grinding processes, abrasives, tools, machines, and systems. Topics feature a selection of areas where relationships between scientific principles and new techniques are yielding improved productivity and better quality. These examples point towards further advances that can fruitfully be pursued. Applications in modern grinding technology range from high-precision kinematics for grinding very large lenses and reflectors through to medium size grinding machine processes and further down to grinding very small components used in micro electro-mechanical systems (MEMS) devices. The importance of material issues is emphasized for the range of conventional engineering steels, through to aerospace materials, ceramics, and composites. It is suggested that future advances in productivity will include the wider application of artificial intelligence and robotics to improve precision, process efficiency, and features required to integrate grinding processes into wider manufacturing systems.

Dressing is a critical issue for optimizing the grinding process. Dresser tool and dresser parameters must be designed according to the grinding wheel material, shape, or even the dimensional and geometrical tolerances of the workpiece and its surface roughness. Likewise, one of the problematic issues of dressers is the wear that they suffer. In order to tackle this issue, the present work characterized the wear of two rotary dressers by analysing the wear behaviour depending on the pit radius of the dressers while studying the influence of the wear on ground surfaces. This work showed that the rotary dresser with a higher pit radius presents wear that is approximately 28% higher than the dresser with a half pit radius.

Abrasive machining methods are used in machining of precision components with
stringent size and surface quality constraints, such as medical devices and automotive
components. Depending on the work material, grinding wheels made out of different
abrasives like, aluminium oxide, CBN or diamond, removes material in the form of
micron sized chips. During machining, the abrasives undergo wear and lose their
cutting ability. Subsequently, the performance of abrasive tools deteriorates over time
without reconditioning of the tool. As a result, controlled removal of abrasives and/or
its bonding materials are crucial mechanisms to be addressed in reconditioning of
fixed abrasive tools. So, this article reviews the mechanical, electro-physical and
chemical material removal mechanisms and their role in self-sharpening of fixed
abrasive tools which pave the way for sustainable machining process

Abrasive grains are subjected to severe cutting conditions as in a grinding wheel. The life of the grinding wheel depends on the ability of an abrasive grain to perform without fracturing under the cutting stresses. In order to improve the behaviour of abrasives, the internal chemistry of the abrasive is normally altered to get different types of abrasive grains-characterised by their toughness. In this work, a bulk surface modification technique is employed to provide a chemical conversion coating onto the abrasive grains, without altering the internal chemistry of the abrasives. The effect of such a coating is studied in two different grinding conditions. It is seen that surface coating on abrasives can improve the grinding performance by delaying the fracture of grains. The results are supported with Optical and Scanning Electron Microscopic analysis of the treated grains and fractured surfaces.

Abrasive grains are subjected to severe cutting conditions as in a grinding wheel. The life of the grinding wheel depends on the ability of an abrasive grain to perform without fracturing under the cutting stresses. In order to improve the behaviour of abrasives, the internal chemistry of the abrasive is normally altered to get different types of abrasive grains-characterised by their toughness. In this work, a bulk surface modification technique is employed to provide a chemical conversion coating onto the abrasive grains, without altering the internal chemistry of the abrasives. The effect of such a coating is studied in two different grinding conditions. It is seen that surface coating on abrasives can improve the grinding performance by delaying the fracture of grains. The results are supported with Optical and Scanning Electron Microscopic analysis of the treated grains and fractured surfaces.

The proper choice of a grinding tool is essential for a productive grinding process and a high quality of the resulting work piece surface. Hence, the grinding wheel structure consisting of abrasive grain material, bonding material and pores has to be composed wisely. We present a new approach for mathematically modelling such grinding wheel structures with the objective of predicting the volumetric composition of the grinding wheel components such that grinding requirements can be met without using trial and error methods. For the model, we focus on a small element of a grinding wheel, such as a cube, which we call volumetric structure element (VSE). In this project, we concentrate on several aspects of the modeling procedure, namely the initial grain arrangement, a collision-free grain rotation and translation algorithm to obtain required grain volume fractions in a VSE, the tetrahedral mesh generation for a whole VSE and the modeling of ceramic bond.

The future of manufacturing companies depends largely on their ability to adapt to
swiftly changing global conditions. These are exemplified by international competition,
rapidly growing intercommunication and the increased significance of environmental
issues [KLOC98a, ENGE02]. Precision machining with geometrically
undefined cutting edges represents a key production engineering technology with
high efficiency, security and machining quality.

This paper mainly concentrates on building up the observational models utilizing reaction surface strategy for surface roughness and metal removal rate (MRR) by considering control factors as wheel speed, feed, depth of cut and hardness of material. The principle target of utilizing response surface methodology (RSM) on surface grinding operation to discovered optimum machining parameters which prompts limit surface roughness and most extreme metal removal rate. EN31 material was selected because of its different applications such as automotive components and mechanical parts. While investigating process parameter in cylindrical grinding machine having silicon carbide wheel, Taguchi technique and L9 Orthogonal array with input factors for examination was executed. The optimized experimental model was demonstrated for many different manufacturers to achieve good surface finish by combination of machining parameters in grinding machine.

The productivity of grinding processes is often limited by the risk of thermal damage of the workpiece surface layer. Therefore, the control of thermal conditions in the grinding arc is of utmost importance for both, industrial practice and academia. In order to optimize the application of the metal working fluid in grinding, devices and methodologies are needed which can assure the measurement of temperatures in grinding or within set-up mode and the control of demand-oriented fluid supply parameters (nozzle angle, nozzle height, nozzle outlet area, fluid jet velocity). The systematic use of such devices and methodologies for fluid supply optimization is enabling reliable and economic grinding processes.

In the present paper, the use of high performance grinding for the description of the twist topography on ground surfaces is investigated. More specifically, the periodic surface structure after finishing with peel grinding and quick-point grinding is considered. Theoretical investigations of the parameters of these grinding processes demonstrate that the twist pattern can be controlled. Furthermore, by considering single-grain material removal, shape and dimensions of the produced chip can be calculated. The single-grain model is also implemented in a CAD based model. The actual trajectory of the grinding grain is graphically represented on the workpiece surface. The chip produced by the grain in each rotation is removed from the surface, indicating the trend of the twist produced via various process parameters.

Grinding process is surface finishing process generally used to smoothen the surfaces by removing the limited quantity of material from the already machined surfaces. Cylindrical grinding or abrasive machining is the most popular machining process of removing metal from a work piece surface in the form of tiny chips by the action of irregularly shaped abrasive particles. In the present study, Taguchi method or Design of experiments has been used to optimize the effect of cylindrical grinding parameters such as wheel speed (rpm), work speed, feed (mm/min.), depth of cut and cutting fluid on the Material Removal Rate of EN15AM steel. Material removal rate measurements were carried out during the machining process on the work piece. EN15AM steel is generally known as free cutting steel and consists of higher machinability. It has several industrial applications in manufacturing of engine shafts, connecting rods, spindles, connecting components etc. The results indicated that grinding wheel speed, work piece speed, table feed rate and depth of cut were the significant factors for the material removal rate. The optimized parameters for material removal rate are grinding wheel speed 1800 rpm, work piece speed 155 rpm, feed rate 275 mm/min. and depth of cut 0.04 mm.