Tool Material Research Articles

Investigating the Influence of Laser-Etched Straight and Wavy Textures on Grinding Efficiency and Tool Quality of WC–Co Carbide Cutting Tools

WC–Co cemented carbide has been widely used as machining tool material due to its good mechanical properties. Grinding is an important process in the manufacture of cemented carbide tools. When grinding tools, there are problems such as excessive grinding force, small chip space, and poor lubrication and cooling performance, which in turn contribute to surface defects such as burrs, burns, and even edge damage such as edge chipping. These problems constrain the use of carbide tools, so that the cutting force is unstable and the machining surface quality is poor when the tool is in service. In this paper, straight-line and wavy-texture patterns were designed and formed on the surface of WC–Co tools using a picosecond laser. Grinding experiments were conducted on the ablated tool using a resin-bonded diamond wheel, and surface morphology, roughness, grinding force, and cutting edge quality were evaluated. Finally, turning experiments were conducted to compare the cutting performance of the tools after conventional and laser-assisted grinding. The experimental results showed that the tools with wavy texture showed superior surface and cutting edge quality, with 53.7% and 51.2% reduction in normal and tangential grinding forces, respectively, and 66.6% maximum reduction in edge chipping for the wavy textured tools. Therefore, this study not only reveals the advantages of laser-assisted grinding in machining WC–Co cutting tools, but also provides a valuable theoretical basis for realizing high-efficiency and low-loss tool machining.

From Powders to Performance-A Comprehensive Study of Two Advanced Cutting Tool Materials Sintered with Pressure Assisted Methods.

This paper presents a comprehensive study of two tool materials designed for the machining of Inconel 718 superalloy, produced through two distinct sintering techniques: High Pressure-High Temperature (HPHT) sintering and Spark Plasma Sintering (SPS). The first composite (marked as BNT), composed of 65 vol% cubic boron nitride (cBN), was sintered from the cBN-TiN-Ti3SiC2 system using the HPHT technique at a pressure of 7.7 GPa. The second composite (marked as AZW) was fabricated from the Al2O3-ZrO2-WC system using SPS at a pressure of 63 MPa. The final phase composition of BNT material differed significantly from the initial composition due to reactions occurred during sintering. In contrast, the phase composition of the AZW ceramic composite before and after sintering was similar. The materials exhibited high quality, as evidenced by a Young's modulus of 580 GPa for BNT and 470 GPa for AZW, along with hardness of 26 GPa for BNT and 21 GPa for AZW. Both composites were used to prepare cutting inserts that were evaluated for their performance in machining Inconel 718 alloy. While both inserts showed durability comparable to their respective reference commercial inserts, they differed in performance and price relative to one another.

The wear resistance of micro spade drills and D-shaped tool materials

The wear resistance of micro spade drills and D-shaped tool materials

Use of patient-centred outcome measures alongside the personal wheelchair budget process in NHS England: A mixed methods approach to exploring the staff and service user experience of using the WATCh and WATCh-Ad.

Personal wheelchair budgets (PWBs) are offered to everyone in England eligible for a wheelchair provided through the National Health Service (NHS) to support their choice of equipment. The WATCh (Wheelchair outcomes Assessment Tool for Children) and related WATCh-Ad for adults are patient-centred outcome measures (PCOMs) developed to help individual users express their main outcome needs when obtaining a wheelchair and rate their satisfaction with subsequent outcomes after receiving their equipment. Use was explored in a real-world setting, aiming to produce guidance for use alongside the PWB process. Three wheelchair service provider organisations across four sites participated. Staff and users completed surveys about their experience of assessments using the WATCh and/or WATCh-Ad. Selected patients were interviewed after receipt of their equipment, and staff were interviewed after experiencing a number of assessments. Thematic analysis was undertaken using the tool, survey and interview data. Results of pre- and post-equipment provision were presented graphically. Information on 75 assessments by 15 staff was obtained. Three-quarters of users or their carers rated the use of the tools in the assessment process as 'helpful' or 'very helpful'. Staff reported that the WATCh or WATCh-Ad had been considered 'useful' in developing individual care plans in around 1 in 3 cases and affected the prescription in 1 in 4 cases. Concerns were expressed about the length of time taken to administer the tools in clinic. However, some staff noted this reduced with more hands-on experience and by providing the tools to users in advance of the appointment. The WATCh and WATCh-Ad PCOMs are suitable for routine use by wheelchair service providers to assist the assessment process. It is recommended that tool materials are provided in advance to users/carers and that staff are allowed time to develop their ways of working with them.

Thermal Management and Biocompatibility in Dry Machining: An Experimental Study of ZrO2-Based Cutting Tool for Bone Machining

This paper aims to assess the thermal properties and biocompatibility of zirconia-based bio ceramic cutting tools for bone surgery compared to stainless steel (SS316L) tools. Because of their biocompatibility, materials such as zirconia (ZrO2) are now widely utilized to reconstruct and replace bone tissue. The study compares wet and dry machining to analyze the effects of temperature and cell behaviour. By performing a quantitative MTT (yellow 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium-bromide) proliferation assay, the current study showed that ZrO2 had higher cell viability and metabolic activity than SS316L. The experiments included primary chondrocyte cells from chicken femoral condyles incubated at 37°C and 5% CO2 with increased cell survival and proliferation in the presence of ZrO2. Thermal performance was evaluated on a CNC vertical milling machine with the help of K-type thermocouples to measure the maximum (Tmax) and average (Tmean) temperature. ZrO2-based tools had resulted in lower Tmax and Tmean throughout the experiment regardless of the cutting parameters, which minimize the thermal injury and improve surgical results. Saline irrigation in wet machining helped in reducing temperature peaks, while dry machining had the advantages of not polluting the environment and being cheaper. Due to its low thermal conductivity and hardness, ZrO2 can be used as an effective material for metal tools in surgical operations to minimize thermal effect and increase the tool lifespan.

SIMULATION 2.5-D COUNTUR MILLING ON CNC-MACHINE

The article discusses a new method of modeling the cutter workpiece engagement during contour 2.5-D milling in order to determine the main process parameter - the material removal rate. A data preparation algorithm and a mathematical model of the engagement of the milling cutter with the workpiece are presented, which allow determining the instantaneous volume of the removed tool material and determining the cutting force according to the mechanical model during machining. For simulation, the representation of the workpiece and the tool in the form of polygons is used, and the cutting process is implemented using the logical operations "intersection" and "difference". This approach allows you to detect the volume of material removed by the tool during a certain simulation iteration, taking into account the geometry of its flutes, and to display the new geometric shape of the workpiece after removing material from it. Such a new form will be used to model the next step of the algorithm, which ensures the continuity of the process. The application of the developed algorithm and mathematical model allows obtaining correct data on the instantaneous volume of removed material, which is subsequently used to predict the cutting force and solve the problem of optimizing the contour 2.5D milling process.

Exploring the Tribological Performance of Mist Lubrication Technique on Machinability Characteristics During Turning S235JR Steel

The main challenges in turning are the quality of the machined part and the cost of tooling. Therefore, optimum machining parameters suitable for turning operations should be selected to achieve the desired quality of the finished product with reduced machining time and cost. The aim of this study is to determine the optimum machining conditions for S235JR low carbon steel without heat treatment, which could include finding the right combination of cutting speed, feed rate, depth of cut and tool material to achieve efficient material removal and desired surface finish. The experimental study, designed with the full factorial method, was carried out with 2 factors of cutting speed and feed rate with selected 2 levels under dry and MQL cutting environment conditions. Results of this study showed that mist lubricating technique overcome the machinability challenges of S235JR steel in terms of low surface quality and high cutting temperature and cutting force.

The Influence of Deep Drawing Parameters on Stresses and Strains in Drawing Tools in the Context of their Durability and Process Load

This publication presents the influence of selected parameters in the deep drawing process on the energy consumption of the entire process. It was analysed how die clearance and the radius of the rounded working edge of the die affect drawing force and work. Modifying these parameters does not directly affect the geometry of the finished stamped product. In addition, it was analysed how modifying the clearance and the radius of the rounding of the working edge of the die affects the magnitudes of stresses and strains in the tools, i.e. the punch and the die. The study was carried out numerically using Ansys Ls-Dyna software. An elastic-plastic model with isotropic hardening was used to model the tools without considering strain rate. This approach makes it possible to assess how a given process will affect the abrasive wear of the working surfaces of the die and punches when the yield stress in the tool material is exceeded. A significant increase in tool life was observed through a reduction in plastic deformation when using clearances greater than the thickness of the sheet metal. Using a larger die edge rounding radius also positively affected tool life, maximum drawing force, and total work.

PROGRESS AND CHALLENGES IN PLUNGE MILLING: A REVIEW OF CURRENT PRACTICES AND FUTURE DIRECTIONS

This review examines recent advancements and ongoing challenges in plunge milling. It is an increasingly utilised machining process renowned for its high material removal rates, particularly with hard-to-machine materials like hardened steels and titanium alloys. Plunge milling’s unique perpendicular tool path offers enhanced stability and reduced lateral cutting forces, making it valuable for applications that demand precision and efficiency, such as aerospace and automotive manufacturing. The paper systematically analyses and synthesises research on critical areas of plunge milling optimization, including tool geometry, material selection, coating technologies, and process parameters, highlighting strategies to mitigate common issues like rapid tool wear and chip evacuation difficulties. In this comprehensive overview, the review introduces theoretical and experimental findings on optimizing plunge milling tools and process parameters—such as cutting speed, feed rate, and coolant delivery—that are essential for improving performance and achieving desirable surface finishes. The paper also explores innovative trends, including AI-driven optimization algorithms and hybrid machining systems, which hold promise for addressing persistent limitations and enhancing plunge milling’s industrial applicability. By consolidating findings from recent studies, this review contributes to a deeper understanding of plunge milling’s role in high-precision manufacturing and identifies future research directions for advancing the process. The insights presented offer practical and strategic implications, aiming to guide ongoing developments in plunge milling technology and its adoption across various precision-oriented industries.

THE INFLUENCE OF DIFFERENT HARDNESS OF THE TOOL MATERIAL ON THE WEAR OF SHM GRINDING WHEELS AND THE SPECIFIC ENERGY INTENSITY OF GRINDING

It was established that conditionally viscous-brittle tool materials (high-speed steels and hard alloys) behave in the same way with an increase in hardness: wheel wear and the specific energy consumption of their grinding decrease. As the hardness of brittle tool oxide-carbide ceramics increases, both wheel wear and the specific energy consumption of grinding, on the contrary, increase. That is, an increase in the hardness of viscous-brittle materials facilitates the separation of elementary chips, less energy is needed for this, and accordingly the wear of the wheel and the specific energy consumption of their grinding are reduced. On brittle ceramics, with increasing hardness, there is no change in chip removal, but harder sludge becomes more abrasive and, as a result, the wear of the wheel and the specific energy consumption of their grinding increase. The conclusion from the literature that hard and less plastic materials require relatively less specific energy for grinding is confirmed by us when comparing materials of approximately the same hardness - hard alloys and ceramics. In ceramics, the energy consumption of grinding is actually four times lower than that of hard alloys.

ASSESSMENT OF THE ROOT MEAN SQUARE DEVIATION ON SURFACES MACHINED BY HIGH-FEED TANGENTIAL TURNING

Recent advancements in machining focus on precision, efficiency, and handling harder materials, driven by sectors like aerospace and automotive. Hard machining, or processing materials over 45 HRC, presents challenges such as rapid tool wear, intense heat, and maintaining dimensional accuracy. Innovations in cutting tool materials and CNC technology have improved these processes, but tool degradation and high forces still complicate machining hardened materials. Surface roughness is a key quality metric, impacting performance factors like wear resistance and fatigue life. By optimizing cutting parameters, manufacturers aim to achieve consistent surface finishes, essential for durability in demanding applications. In this paper, the effect of the input parameters (depth of cut, feed, and cutting speed) are analysed on selected surface roughness parameters. The setup parameters were selected according to the full factorial design of experiment method. The results showed that higher feed rates resulted in rougher finishes, leading to greater spacing between profile elements and steeper surface profiles in the studied range.

Investigation of tool wear behavior in CFRP drilling by using different tool materials

Abstract The industrial usage of Carbon fiber reinforced polymers (CFRP) has increased significantly over the past few years due to its distinguished characteristics like great strength-to-weight ratio, fatigue resistance, superior damage tolerance, excellent corrosion resistance, etc Machining of CFRP differs from traditional machining due to its structure. This experimental study aims to investigate the effect of drill bit material on tool wear and to optimize the material selection process of twist drill bits during CNC drilling of CFRP regarding the output of tool wear, thrust forces, and torque generated during the drilling process. Four twist drill bits with dissimilar materials (i.e., HSS-4341, HSS-M2, HSS-Co, and Tungsten Carbide) having the same size and diameter (3 mm) were selected and used for CNC drilling on CFRP plates. During the drilling process, thrust forces and torque were calculated with the help of a dynamometer for each drilled hole. Moreover, the tool wear was seen and compared after the 1st hole and 20th hole for each drill bit to analyze the behavior of different tool materials toward CFRP machining. The results showed that Tungsten Carbide is the most suitable tool material for CFRP drilling as it yielded the lowest thrust forces and lowest torque for all 20 holes. Moreover, the Tungsten Carbide had the lowest tool wear among all the drill bits. These results imply that tool life can be significantly elevated if Tungsten Carbide is to be used for machining of CFRP.

Effect of diamond grain size on mechanical properties and cutting performance of PCD tool in milling of Cf/SiC composites

The polycrystalline diamond (PCD) tools have excellent cutting performance in machining composites. However, the tool wear mechanism of PCD tools in milling Cf/SiC composites remains unclear. There are few researches on the effect of diamond grain size on the cutting performance of PCD tools and material removal mechanism. In this paper, four PCD samples with different grain sizes were prepared under high-temperature and high-pressure condition. The microstructure, flexural strength, and cutting performance of PCD samples was tested. The wear mechanism of the tools was analyzed by observing the wear morphology of the front and rear cutting surfaces of the PCD tools. The influence of diamond grain size on the cutting performance of PCD tools was investigated in terms of tool life, surface roughness and material removal mechanism. The results indicated that the highest bending strength was found in the PCD sample with the grain size of 5 μm, as the diamond grain size increased, the bending strength of the PCD tool decreased. Tool failure was caused by fiber bundles and chip dust scratching the binder and diamond grains. In the same cutting distance, due to the difference in bonding between diamonds of different grain sizes. The 2 μm∼30 μm grain size of the PCD tool wear was the slowest, 5 μm grain size of the fastest PCD tool wear. As the grain size decreased, the machined surface quality of Cf/SiC composites improved. The fiber removal mechanisms employed the gradual transition from shear removal to bending removal as the grain size increased.

Effects of Cutting Parameters on Tool Wear in Milling Inconel 625 Superalloys with a SiAlON Ceramic and the Prediction of Tool Life

Inconel 625 superalloys are widely preferred in various industries because of their superior mechanical properties at high temperatures. The superior properties they exhibit make the machinability of Inconel 625 alloys difficult. This situation can cause rapid wear of the cutting tools, making the cutting tool unusable in very short periods of time and causing deterioration of the workpiece surface quality. Therefore, improving the machining performance of Inconel 625 alloys, optimizing the machining parameters and using the optimum cutting tool material and geometry are important. In this study, SiAlON ceramic cutting tools, which have been widely used in recent years, were preferred. SiAlON tools supplied in raw rod form were subjected to various processes and finalized into final products. The effects of three different cutting speeds (vc), feed rates (f) and axial depth of cut (ap) on tool life (T), wear patterns and mechanisms were investigated with 9 tests designed according to the Taguchi L9 orthogonal array. The results revealed that the f values, the effects of which were analysed, had the most significant effect on T. By performing regression analysis with T values, the coefficients used in the extended Taylor T equation were determined, and T predictions were obtained. The regression model was found to be consistent with the experimental results, with an effect of 99.34%, and the model was significant according to analysis of variance. The predominant wear patterns of the cutting tools were flaking at a low vc, nose collapse at a high vc and an adhered workpiece under all conditions. The wear mechanism was found to be predominantly adhesion and fracture. The presence of Ni, Cr, Mo, Nb and Fe on the cutting tool surface was determined, and the effect of the concentrations was observed to increase/decrease significantly depending on the parameter values examined.

Comparative Analysis of Aluminium 6061-T6 With Different Stock Leaves Setting on Holes True Position: A Case Study

With the evolution of industrial technology, improved machining processes have been developed. With the expansion of machining processes, machining characteristics alter according to the tool and work materials, tools used, machining technique used, etc., increasing surface smoothness, dimensional accuracy, and tool wear. Geometric error is a problem in precision machining due to parameter settings. This research aims to analyse the effect of stock leave setup on achieving precise product hole positions and improving machining process efficiency. The substrate involved was AL6061-T6. This study involved the use of MasterCAM software for simulation analysis to predict the effectiveness of the machining process. Then, the machining process was implemented with different stock leaves of 4 mm and 1 mm using a 5-axis Mazak machine. The result reveals the coordinate measurement machine (CMM) reading is proportional to the stock leave setup. The small reading value of CMM produces better accuracy cutting in machining process. In addition, a small value of stock leave produces a hole position within the specification due to adding additional processes compared to the high value of stock leave. Thus, with suitable parameters, all machining processes can produce a good accuracy of finishing parts and meet customer requirements.

Research status of cutting machining NiTi shape memory alloys: a comprehensive review

NiTi shape memory alloys (SMA) have garnered significant interest owing to their shape memory effect, superior corosion resistance, and biocompatibility. This paper reviewed the current research status of cutting machining for NiTi SMA, focusing on turning, milling, and drilling processes, emphasizing the influence of various cutting parameters, tool materials, and cooling methods on machining performance. The optimal turning effect under dry cutting circumstances is achieved when the cutting speed surpasses 100 m/min. The application of Minimum Quantity Lubrication (MQL) in milling, alongside the use of cold air and the optimization of parameters such as feed rate and cutting depth, could diminish cutting force and temperature, thus reducing burr formation. Cemented carbide and high-speed steel covered with TiN are the ideal materials for drilling tools, and the use of substantial cutting fluid yields superior cutting performance compared to MQL. This review concludes that, despite advancements in the study of machining NiTi shape memory alloys, further research is necessary to enhance the efficiency and quality of NiTi SMA machining, particularly with tool material selection and cooling techniques. Finally, based on the current research results, this paper proposes possible future research directions, which provides valuable theoretical guidance for the processing research of NiTi SMA.

Toughening mechanisms taking into account growth kinetics of SiC whiskers for bionic ceramic cutting tool materials

The growth mechanism and kinetic characteristics of SiC whiskers for novel bionic ceramic cutting tools were analyzed by modified Arrhenius equation, which reveals the regulation effect of SiC whisker growth on the microstructure evolution. Furthermore, the influence of the growth mechanism on the toughening mechanism under shear and indentation failure was investigated. The results showed that the formed transition area at the bonding interface can improve the residual thermal stress distribution. The synergistic effect of multiple macro/micro-toughening mechanisms and interfacial strengthening mechanisms enabled the bionic ceramic cutting tool materials to exhibit excellent fracture resistance under shear and indentation failure.

Comparative study and experimental validation of cutting forces in high-speed ball-end milling for AL 7075-T6 and AL 6061-T6 alloys

This study examines the importance of precise cutting force prediction during high-speed ball-end milling of the AL 7075-T6 and AL 6061-T6 aluminum alloys, which are widely used in the aerospace and automotive industries, because to their strength and fatigue resistance. Predicting cutting forces is critical for optimizing milling conditions and creating high-quality surfaces. We have used a mechanistic model to estimate cutting forces based on experimental data. To generate the more precise predictions, the developed model takes into account tool geometry, cutting settings and material properties. We have measure the cutting forces on a CNC SOMAB DIAM 850 milling machine by using a Kistler 9257A dynamometer. We have done simulations with MATLAB software. The results reveal that the mechanistic model accurately predicts both alloys. ALU 7075-T6 produces higher cutting forces because to its increased strength. This comparative research demonstrates that the mechanistic approach is useful in forecasting cutting forces in high-speed ball-end milling of aluminum alloys, providing useful insights for improving machining operations.

Use of osseous materials during the Chalcolithic in Northeastern Bulgaria (based on materials of Polyanitsa tell)

Many Chalcolithic cultures of the Balkan-Danube region used antler, animal bones, boar tusks and shells as raw materials for tools, household and votive items, as well as jewelry. The unique collection of such objects found in 1973–1974 during the archaeological study of the Polyanitsa tell (Northeastern Bulgaria), is particularly numerous and diverse (266 items). Experimental and traceological studies of part of this collection made it possible to characterize the manufacturing technology of these products, as well as the functional purpose of many of them. Among the industrial equipment, tools were found that were used in agriculture, processing flint, wood, hides and skins, and ceramics. It should be noted that some flint tools, found at the settlement, were used for processing bone/antler. This fact, as well as finds of blanks and unfinished items made of bone/antler, indicate their local production. The quality and the wide range of products of the bone processing industry serve as proof of the high level of its development and demand for such utensils in the economic and domestic activities of the population of the Chalcolithic sites of Northeastern Bulgaria.

The generation mechanism of cutting heat and the theoretical prediction model for temperature on the rake face of the cutting tool in Zirconia ceramics

Cutting temperature and its distribution are crucial factors influencing tool strength and wear rate, due to the hardness and brittleness of Zirconia (ZrO2) ceramics, significant challenges arise in both direct temperature measurement in the cutting zone and theoretical analysis of cutting heat. Thus, focusing on the turning characteristics of ZrO2 ceramics, this study analyzes the mechanism of cutting heat generation and proposes utilizing thermodynamic state equations to determine the cutting heat source on rake face of tool. Based on the heat source method, a theoretically prediction model for temperature distribution on rake face is established. This model considers primary cutting parameters, workpiece material properties, crack fracture characteristics of the machined surface, and thermal characterizations of the tool material. The relationship between tool wear and cutting temperature is experimentally analyzed to determine the characteristic temperature that indicates the initial stage of tool wear. The validity of the theoretical model is verified, as the predicted results show high consistency with experimental results within the range of experimental parameters, with a relative error within 15.2 %.The results reveal the highest temperature during brittle cutting occurs within the cutting layer area, with the highest temperature occurring approximately 50 μm from the tool tip, followed by a gradual decrease beyond 150-200 μm. This study also demonstrates that cutting heat in ceramic turning does not solely originate from friction heat between tool flank-workpiece but also includes impact heat from tool rake face-workpiece, which under certain cutting parameters exerts a more significant influence on cutting temperature. This model can facilitate the selection and optimization of cutting process parameters for brittle materials and provide a theoretical basis for analyzing the relationship between tool thermal damage, thermophysical properties, and tool wear.