Textured Tools Research Articles

Surgical Tool Segmentation Using Generative Adversarial Networks With Unpaired Training Data

Surgical tool segmentation is a challenging and crucial task for computer and robot-assisted surgery. Supervised learning approaches have shown great success for this task. However, they need a large number of paired training data. Based on Generative Adversarial Networks (GAN), unpaired image-to-image translation (I2I) techniques (like CycleGAN and dualGAN) have been proposed to avoid the requirement of paired data and have been employed for surgical tool segmentation. The unpaired I2I methods avoid annotating images for domain changes. Instead of using them directly for the segmentation task, we propose new GAN-based methods for unpaired I2I by embedding a specific constraint for segmentation, namely each pixel of input image belongs to either background or surgical tool. Our methods simplify the architectures of existing unpaired I2I with a reduced number of generators and discriminators. Compared with dualGAN, the proposed strategies have a faster training process without reducing the accuracy of the segmentation. Besides, we show that, using textured tool images as annotated samples to train discriminators, unpaired I2I (including our methods) can achieve simultaneous tool image segmentation and repair (such as reflection removal and tool inpainting). The proposed strategies are validated for image segmentation of a flexible tool and for in vivo images from the EndoVis dataset.

Effects of rake surface texture geometries on the performance of single-point cutting tools in hard turning of titanium alloy

Texturing of cutting tool surfaces is emerging as one of the viable solutions to enhance tribological characteristics during machining. Apart from the cutting regime used, the effectiveness of textured tools also depends on the texture geometries. Accordingly, the present study investigates the effect of four different micro-textures on the rake surface of cutting tool inserts in hard turning of Ti-6Al-4V alloys. It specifically addresses the effect of micro-textures on the tool-chip contact length and chip morphology. This study also compares the experimental tool-chip contact length with a new model proposed for inserts with textures. The effect of different insert texture geometries on chip morphology has been investigated by characterizing the chips produced during the cutting. Further, the effects of texture geometries on the parameters like chip compression ratio and shear angle were examined. A detailed analysis has beeen carried out using inserts with and without micro textures to understand their effect on the mechanics of machining. Quantitative predictions were made on the effectiveness of the texture geometry in reducing the cutting forces and friction during machining.

Performance improvement of turning operation during processing of AISI 304 with novel textured tools under minimum quantity lubrication using hybrid optimization technique

ABSTRACT Manufacturing cost and productivity in machining systems can be significantly affected by the optimized input sources. Further, metal cutting industries have shown curiosity toward surface textured tools due to gain in productivity. In this context, new textured tools were developed and machinability studies were carried out on AISI 304 material under eco-friendly technique namely Minimum Quantity Lubrication (MQL) with so developed tools. The novel textured tools were fabricated by making circular micro pit holes on the rake face of the tungsten carbide tool using laser technology. In this work, a new weighted gray relation analysis (WGRA) integrated Jaya algorithm is proposed to determine the best cutting parameters. From the result, it is found that 54%, 7% respective reduction in surface roughness (Ra) and tool wear (Vb) and 27% increment in material removal rate (MRR) at the optimum conditions determined by the proposed optimization technique. It is concluded that the proposed work meets the environmental sustainability requirements and improved the turning process performance.

Micro-electrochemical jet machining of large area microtexturing with tool movement strategy

ABSTRACT Microtextured surfaces, particularly circular micropattern, significantly enhance the function and performance of microfabricated devices and engineering parts. A distinctive and inventive concept of maskless microelectrochemical jet machining (EJM) is utilized for producing the microcircular pattern over large area. In this research work, an advanced concept, i.e. maskless micro-EJM is presented to produce the microtextures on large area using the reusable masked tool movement strategy on stainless steel. One masked patterned tool can fabricate many high-quality micropatterned samples over large area using the tool movement strategy. High-pressure electrolyte flow through textured tool is developed to acquire the high-quality microtextures with controlled dimensions. The machining consequence of substantial input parameters, i.e. IEG, flow rate and frequency on microdimpled characteristics such as MRR, overcut, depth, and R a is explored. Microdimples of 5.3 mg/min MRR, 20.07 µm overcut, 13.5 µm depth, and 0.0601 µm surface roughness and 5.29 cm2 machining area are successfully fabricated using the reusable masked tool. The present study confirms that it is achievable to acquire the large area microtexturing using this innovative technique.

Design and analysis on textured cutting tool

Cutting tool plays a major role in manufacturing process to reduce cost and machining time. Various number of researches had been conducted to optimize machining process and to find a way to extend the life of the cutting tool. To improve the process quality, the surface texturing is also performed on the cutting tool. In this paper, the machinability of textured tungsten carbide cutting tool for turning aluminum alloy is proposed. The texture pattern used in parallel stripes and vertical stripes on the flank of the cutting tool. The simulations of the texture pattern were engraved on the tool using Abaqus/CAE 6.14 software chip formation simulation had been done. Boundary conditions for the work is defined as displacement and rotation and the velocity is defined as 0.2 m/s. The meshing of the part and work is done in square mesh pattern and the discretization rate is 0.0005. From the analysis, the chip flow direction and the shear zone are discussed in detail. Subsequently, the energy developed on machine the material has been evaluated with the results of cutting force. The maximum cutting force developed in the plain cutting tool is 1.468 N. however, for the textured cutting tool has 1.207 N for horizontal texture tool and 3.249 N vertical textured cutting tool. It indicates that the horizontal has a built – up edge nature and supports to shear the material conveniently than the other two conditions. In addition, the stress induced during the machining process is also compared for interpretation. Thus, the inference is made to justify that the tool life is increased when surface texturing is done compared to the tool life for non-textured tool.

Machining of hard materials using textured tool with minimum quantity nano-green cutting fluid

Metal cutting causes severe friction and heat generation in the machining zone. Previously, petroleum-based cutting fluids were applied for reducing friction and machining temperature at the machining zone. Nowadays, nano-cutting fluids are preferred owing to their higher thermal conductivity and better lubricating ability. However, during machining of hard materials (hardness, ≥50 HRC), the effectiveness of these nano-cutting fluids is limited, as they rarely reach to the cutting edge of cutting tool because of high normal stresses. In this regard, the combination of rake face micro-textured cutting tool with indigenously synthesized nano-green cutting fluids under in-house developed minimum quantity cutting fluid (MQCF) environment is accomplished for hard machining experiments. For comparison, hard machining experiments are also performed under dry machining, green cutting fluid and nano-green cutting fluid (NGCF) with untextured cutting tools. Detailed analysis shows significant improvement in hard machining performance using combination of micro-textured tools with NGCF corresponding to forces, chip-tool interface friction, workpiece surface roughness and chip morphology. It is attributed to better infiltration of NGCF in-between chip-tool interface by virtue of micro-textures present on the cutting tool rake face. Further, the proposed analytical model captures the effect of textures on the tool surface in the same way as reduced contact tools. It is in a good agreement with corresponding experimental cutting forces.

Laser Processing of Hard and Ultra-Hard Materials for Micro-Machining and Surface Engineering Applications.

Polycrystalline diamonds, polycrystalline cubic boron nitrides and tungsten carbides are considered difficult to process due to their superior mechanical (hardness, toughness) and wear properties. This paper aims to review the recent progress in the use of lasers to texture hard and ultra-hard materials to a high and reproducible quality. The effect of wavelength, beam type, pulse duration, fluence, and scanning speed is extensively reviewed, and the resulting laser mechanisms, induced damage, surface integrity, and existing challenges discussed. The cutting performance of different textures in real applications is examined, and the key influence of texture size, texture geometry, area ratio, area density, orientation, and solid lubricants is highlighted. Pulsed laser ablation (PLA) is an established method for surface texturing. Defects include melt debris, unwanted allotropic phase transitions, recast layer, porosity, and cracking, leading to non-uniform mechanical properties and surface roughness in fabricated textures. An evaluation of the main laser parameters indicates that shorter pulse durations (ns—fs), fluences greater than the ablation threshold, and optimised multi-pass scanning speeds can deliver sufficient energy to create textures to the required depth and profile with minimal defects. Surface texturing improves the tribological performance of cutting tools in dry conditions, reducing coefficient of friction (COF), cutting forces, wear, machining temperature, and adhesion. It is evident that cutting conditions (feed speed, workpiece material) have a primary role in the performance of textured tools. The identified gaps in laser surface texturing and texture performance are detailed to provide future trends and research directions in the field.

Generation of square micropattern using electrochemical micromachining

Surface microtexturing accomplishes a substantial role in enhancing the interfacial functional performance of machine-driven components. For producing good-quality square micropatterns, maskless electrochemical micromachining (EMM) is a viable option. Maskless EMM is employed for producing micropatterns, wherein the workpiece remains close by interaction with the mask tightly enclosed to the coated tool surface, and the electrolysis of job involves in the enclosed cell. The special micropatterning setup is developed to produce the good quality square micropatterns including micropatterning cell, pulsed electrical unit and perpendicular cross flow electrolyte system. The developed flow method on the job surface in this unit produces better good quality micropatterns. A reused textured tool and developed flow method is applied in maskless EMM in an enclosed unit, which eradicates the sludges and fabricate micropatterns with higher depth. This unique method is an efficient approach for improving the dimensional accuracy of micropatterns. The influences of input criteria, viz. voltage, duty ratio and frequency are studied on surface roughness, current efficiency, length overcut, and textured depth using this technique. The experimental outcomes show that the best parametric combination, viz. 30% duty ratio, 5 kHz frequency and 8 V voltage, enhances the micropatterned quality. A study has been approached based on micrographs for attaining the best input criteria combination.

Physics-Based Simulations of Chip Flow over Micro-Textured Cutting Tool in Orthogonal Cutting of Alloy Steel

Physics-based process simulations have the potential to allow virtual process design and the development of digital twins for smart machining applications. This paper presents 3D cutting simulations using the finite element method (FEM) and investigates the physical state variables that are fundamental to the reduction in cutting forces, friction, and tool wear when micro-textured cutting tools are employed. For this goal, textured cemented carbide cutting tool inserts are designed, fabricated, and tested in the orthogonal dry cutting of a nickel-chromium-molybdenum alloy steel. Cutting forces and friction coefficients are compared against the non-textured tool, revealing the effects of texture parameters. Chip flow over the textured tool surface and process variables at the chip-tool contact are investigated and compared. The results reveal the fundamental sources of such improvements. Archard’s wear rate as a composition of process variables is utilized to compare experimental and simulated wear on the textured cutting tools. The effects of texture and cutting conditions on tool wear and adhesion characteristics are further discussed on the simulation results with experimental comparisons. It was found that the results obtained from these simulations provide further fundamental insights about the micro-textured cutting tools.

FEM SIMULATION ASSESSMENT OF MACHINING TITANIUM GRADE 2 USING TEXTURED TOOL

This work focuses on the 3D numerical investigation of machinability criteria using textured tools for the dry machining of titanium grade 2. For the development of the 3D finite element model, DEFORM-3D (version 10.1) software was used. Dimple patterns were created nearer to the cutting edge region on the rake face of carbide inserts so as to predict their effect and investigate the machinability criteria. Comparison of dimple-textured tool was being made with a conventional tool based on the cutting forces ([Formula: see text], [Formula: see text] and [Formula: see text], cutting temperature, tool wear, effective stress and effective strain. The numerical study revealed that the dimple-patterned tool improved the machinability of titanium grade 2. The cutting forces (tangential cutting force, feed force and radial force) reduced while machining with a dimple-patterned tool as compared to the conventional nontextured tool. There was an enhancement of tool life and a decrease in effective stress and effective strain while dry turning grade-2 titanium alloy using the textured tool.

The effect of micro-texture on wear resistance of WC/Co-based tools during cutting Ti-6Al-4V

Titanium alloy as an important material used in the aerospace industry and automotive field has many advantages such as excellent specific strength, good corrosion resistance, and ultra-low temperature performance. However, there are still some difficulties during the cutting of Ti-6Al-4V, such as severe tool wear which reduces the surface quality of work piece. Textures could protect the tool from further wear and improve the tool life, and cutting productivity. In this work, femtosecond laser was used to make textures with different orientations (vertical, parallel, and vertical to the main cutting edge) on the rake face of carbide-tipped cutting tool to research the influence of different textures directions on the cutting performance. The results found that using parallel textured tools could reduce the friction coefficient by 14%. Compared with untextured tools, the rake face wear of parallel textures tools is reduced by 35–70% and surface roughness improved by 29%, which is owned to smallest the tool-chip contact area of tool with parallel microstructure.

Improvement of thread turning process using micro-hole textured solid-lubricant embedded tools

In this paper, the thread turning of aluminum 7075-T6 alloy is studied using micro-hole textured solid-lubricant embedded carbide inserts. The primary focus of this work is to enhance the performance of the thread turning process for producing high quality threaded parts. To achieve this, micro-holes were generated by laser micro-machining on the rake face of tools and then, MoS2 and CNT (carbon nanotube) solid-lubricants were embedded into micro-holes. The effects of micro-holes and solid-lubrication on the performance of the thread turning process were examined using traditional tool ( T0), micro-hole textured tool ( T1), micro-hole textured MoS2 embedded tool ( T2), and micro-hole textured CNT embedded tool ( T3). In this study, cutting forces, chip-tool contact length, built-up edge (BUE), surface roughness, and operating cost were investigated. The influence of micro-hole generation on the mechanical strength of cutting inserts was evaluated using the finite element method. The results showed that the fabrication of the micro-holes on the rake surface of cutting inserts has no significant effect on the mechanical strength of the tools. The comparisons of our method with traditional tools demonstrated that the cutting performance improved in the threading process. Our results reveal that the main cutting force, radial thrust force, surface roughness, built-up edge, and chip-tool contact length reduced 37.1%, 40.9%, 37.9%, 58.3%, and 38.2%, respectively, as T3 tools are applied in this process. A cost analysis, based on estimated tooling costs, showed that the T3 tool can yield an 18% reduction in overall operating cost.

Optimization of dimensional accuracy in threading process using solid-lubricant embedded textured tools

ABSTRACT In this paper, the parameters of microtextured tools were studied in the threading of aluminum 7075-T6 alloy. The primary focus of this work is to optimize the parameters of microtextured tools using the RSM method to produce high-accuracy threaded parts. Microtextures were generated through laser micromachining on the rake surface of carbide inserts. Geometric parameters considered were diameter, depth, and distance of microtextures and lubricant type. The maximum deflection of the workpiece in the cutting process was considered as the output of experiments. Optimal microtexture factors were obtained using the RSM method. Based on optimization results, the optimal level of diameter, depth, and distance of microtextures is 95, 15, and 50 µm, respectively, and the microhole-textured CNT-embedded tool is more efficient than MoS2-embedded tool and traditional tools. Our results reveal that the maximum deflection of the workpiece reduced up to 40.2% as the microhole-textured CNT-embedded tool is applied in this process.

Precast Textured Tool and the Construction of an Intensive Grinding Process Based on It

The article deals with the construction of an intensive process of grinding materials using a precast textured wheel and a device for the centrifugal giving of lubricating and cooling liquid (LCL) directly to the local contact zones of the cutting and pressing abrasive grains with the processed material. The design of the tool and an effective method of coolant giving to the cutting zone are described, which provide the required roughness of the treated surface and eliminate structural changes in the surface layer under intensive grinding conditions. An increase in the rate of heat removal from the grinding zone is achieved by using a textured tool design, a device for centrifugal giving of coolant and accelerating the liquid to approximately the cutting speed. A method for constructing an intensive grinding process with a precast textured tool has been developed, the implementation of which can significantly increase the processing efficiency. The results of the research are recommended for grinding steels, cast iron and other metals and alloys that are prone to the formation of cauterization, tensile residual stresses and other thermal defects that occur under the influence of high temperature in the grinding zone.

Wettability Control on YW2 Cemented Carbide Surface by Femtosecond Laser Irradiation

The surface wettability control of cemented carbide tools is beneficial to the improvement of tool life and surface quality of workpieces in wet cutting. To clarify the correlation between the surface topography and wettability, squared microdimples are fabricated on the cemented carbide surface using a femtosecond laser. The dependencies of the side length, the depth, and the distribution density of squared microdimples on the surface topography and contact angle are studied. As the average laser power, and the number of scanning passes, increase, both the side length and depth of the squared microdimples increase. The contact angle decreases from hydrophilic to superhydrophilic. Moreover, the roughness height parameters have a great influence on the surface wettability, the larger the surface arithmetic average height, the smaller the kurtosis, the larger the skewness, and the better the hydrophilicity. The results of the scanning electron microscope (SEM) and energy‐dispersive spectrometer (EDS) reflect that the changes in the micro–nano protrusions, carbon, and oxygen elements cause deviation between the calculated contact angle and the actual contact angle. The friction coefficient of textured tools is lower than that of untextured tools at high sliding speed. Reasonable design of surface texture accurately controls surface wettability.

Performance study of dimple and channel textured tools during turning of Inconel-718

Alterations in cutting tool surfaces are being looked at as futuristic developments in cutting tool technology. Tool surface texturing by subtractive as well as an additive way can contribute to the tool performance and productivity improvement. The tool textures can be in the range of nano to micro-level. They help to reduce friction, manage the heat-induced during machining and facilitate chip removal. For textured surfaces, small cavities or dimples uniformly distributed over the sliding surface have been found to have the best tribological effect. In this study, two different micro-texture patterns i.e., micro-dimple and micro-channel were made on the rake-face close to the main cutting edge of the carbide tool insert. Ultra-short pulsed (nanosecond) fiber laser has been used for texturing. An array of texture patterns with 80 µm width/diameter and 70 µm depth has been engraved on the uncoated tungsten carbide tool. The textured inserts have been used for machining trials at 30 m/min to 100 m/min for Inconel 718 to compare the relative performance of the textures in terms of three components of cutting force and machined surface roughness. The experimental observations showed higher components of cutting force for channel textured tools in comparison to dimple textured tools. However, a better surface finish has been observed with channel textured tools. Cutting forces has been observed varying significantly with cutting speed in the case of dimple textured tools. Radial forces were observed higher in magnitude followed by tangential cutting force and feed force for both the textured tools. This study suggests having further studies considering the effect of different texture patterns on the cutting forces, surface roughness, and tool life while turning Inconel 718.

Cutting Performance Analysis of Surface Textured Tools in Dry Turning: Optimisation of process parameters

Owing to minimum quantity or no use of toxic coolants, the dry machining technique has been evidenced to be a versatile sustainable method. However, during dry machining of ductile alloys, the severe tool wear and metal adhesion on the rake face of the cutting tool has been a matter of great concern. In the present work, an attempt has been made to assess the improvement in the tribological conditions in dry cutting by providing surface texturing on the rake face of High-Speed Steel (HSS) cutting tool. Dimples were produced on the rake surface of the HSS tool using pulsed Nd: YAG Laser and dry turning of pure aluminium is performed using the textured tool based on Taguchi’s L9 orthogonal array (OA) experimental design. The dry cutting of pure aluminium was also performed using the conventional/un-textured tool and the obtained results are used for comparison purpose. Improved turning performance in terms of material removal rate and surface roughness is found from the conformation tests using optimum process parameter determined by the Taguchi analysis. The ANOVA results suggests the effectiveness of using the textured tools during dry machining is significantly affected by feed and speed.

Micro-textured cutting tools: Phenomenological analysis and design recommendations

One of the effective strategies to improve dry machining processes is the implementation of micro-textured cutting tools. Micro-textures decrease the chip-tool contact length and thus reduce friction and heat which lead to better surface quality and longer tool life. However, micro-cutting of the bottom side of the chip, known as derivative cutting, is an issue when using textured tools. Derivative cutting increases the cutting forces, heat, and ultimately tool wear. This paper investigates the effect of micro-texture design parameters on the occurrence of derivative cutting and offers design recommendations when preparing micro-grooves to eliminate/reduce the severity of this phenomenon.

Study on cutting mechanism of mold steel in ultrasonic elliptical vibration cutting with textured tool

Study on cutting mechanism of mold steel in ultrasonic elliptical vibration cutting with textured tool

Influence of maskless electrochemical micromachining process parameters during microtexturing

Abstract Maskless electrochemical micromachining (EMM) is a prospective procedure for elevated precision microtexturing. Particularly the microtexturing of substrates without any mechanical influence or heat affect is a substantial characteristic for this process. Moreover, the anodic dissolution performance of job material is only characterized by its electrochemical features. This creates maskless EMM an alternative procedure for electrochemically hard to machine materials. Maskless EMM method with developed vertical cross flow method has been recommended involving microtexturing with higher symmetrical uniformity that are produced on stainless steel (SS304) surface. In this paper, maskless EMM method is a promising cost-efficient substitute for microtexturing containing rectangular micropatterns. The advanced setup has the developed machining cell, flow system and unique electrical connection unit. The machining unit has fixturing arrangements of electrodes, flow system, and electrical connection arrangement. Within the machining unit, the advanced flow scheme is a vertical cross flow system that aids in the fabrication of high-quality microtextured surface. One coated textured tool can produce many rectangular micropatterns with high quality. The effect of process parameters such as electrolyte concentration, machining time, and inter electrode gap (IEG) is evaluated on surface roughness (Ra), length overcut, machining depth and width overcut when fabricating micropatterns is investigated. The best process variables i.e., 50 μm IEG, 6 s machining time and 15 g/l electrolyte concentration manufacture good quality micropatterns.