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A finite element model for numerical simulation of non‐steady but continuous chip formation under orthogonal cutting conditions is described. The problem is treated as coupled thermo‐mechanical. A velocity approach has been adopted for the proposed solution. The computational algorithm takes care of dynamic contact conditions and makes use of an automatic remeshing procedure. The results of simulation yield complete history of chip initiation and growth as well as distributions of strain rate, strain, stress and temperature. The paper includes a detailed presentation of computational results for an illustrative case.

Developing countries are now fully aware of the importance of the manufacturing sector as a key factor of growth and transformation of their economy. Improved technology and method of manufacturing have produced quality products at reduced cost and this has advanced development. The study uses experimental methods based on orthogonal cutting process to measure the cutting forces using a dynamometer while machining the test specimen with a diamond cutting tool at 5° rake angle. The machining forces for the dry cutting are higher than the wet cutting in the range of 31.2‐44.31, 32.09‐40.67, 29.10‐35.62, 29.21‐45.03 and 29.94‐38.74 percent for “as received”, normalized, tempered, annealed and hardened specimen, respectively. For annealed and hardened test specimen, the cutting speed of 245 rpm is ideal for machining when it gives a fine surface finish. Also for precision machining, dry turning is by far a better cost saver and cleaner option than wet turning. This is because though wet machining is relatively more expensive, it is hazardous to health. Normalized and annealed specimens require lower cutting forces and chip formation is slow. Tempering and annealing medium carbon steel facilitated rapid machining and chip formation is rapid. It is therefore an advantage to temper or anneal medium carbon steel before processing into component parts in the manufacturing industry as it saves cost and gives fine component surface finish. The paper aims to address these issues.

Tensile samples are prepared from medium carbon steel. These prepared samples were later subjected to heat‐treatment operations (normalizing, hardening, tempering and annealing). Tensile test were carried out to obtain the materials' sensitive properties used in the modeling equations. An experimental method based on orthogonal cutting is adopted to measure the machining forces using techquipment dynamometer.

It is observed that as t_u increases, F_c increases for all conditions, i.e. as t_u increases, tool‐chip contact area increases and increasing frictional force, also volume of metal removal increase resulting in increasing energy input. F_c values is highest for the normalized followed by that of the annealed. They are less for hardened and tempered. This is because of the mode of chip formation whereby ductile structures give continuous chips as against discontinuous structure for the hardened and quenched structures. Input energy is high for the former and low for the later. This is confirmed by the m values and observed chips.

There is no limitation, except for the instrumentation. On availability of the appropriate equipment, like the Kystler dynamometer for the correct reading of the experimental results.

The implication is limited to the workshop hazard during the experiment.

The research work is original.

The purpose of this paper is to examine the quality of the turned surface. The quality of the surface produced depends on the nature of the chips, which are produced while turning metal matrix composites. This quality is a function of the machining parameters, tool material, tool configuration and elements of the composites.

In this study, the turning of AA7075/15 wt.% SiC (particle size 20–40 µm) composites is investigated. Thirty experiments were conducted, and the chip-formation mechanism in turning AA7075/SiCp composites at various combinations of cutting speeds, feed and depth of cuts was studied.

It is observed from the response surface methodology-based experimentation that in turning of coarser reinforcement (particle size 20–40 µm) composites, total gross fracture occurs. This causes small slices of chips and a higher shear plane angle. The nature of chips produced at various combinations of cutting speeds, feed and depth of cuts is different. The chips generated were segmented, spiral in cylindrical form, connected C type, chips with saw tooth, curled chips, washer C type chips, half-curved segmented chips and small-radii segmented chips.

The novelty of this research is that, so far, very little work has been published on the detailed analysis of chips produced during turning of AA7075/15 wt.% SiC (particle size 20–40 µm) composites.

This paper aims to provide a detailed review of various cutting fluids (CFs).

Friction and wear are inevitable in machine parts in motion. The industrial sector uses various kinds of lubricants, which include engine oils, CFs, hydraulic fluids, greases, etc. to control friction and wear. The main purpose of using CF is to remove heat produced during machining and to reduce cutting forces, tool wear and energy associated with it. Thus, it increases the productivity and quality of the manufacturing process. But more than 80% of the CFs used in the industries now are mineral oil-based. These mineral oils and additives are highly undesirable because of their toxicity, nonbiodegradability, pollution and ecological problems. Hence, these petroleum-based oils in the lubrication system can be substituted with alternatives such as vegetable-based CF. Several studies are being conducted in the field of eco-friendly CFs. Because of the variance in fatty acid profile and availability, the selection of vegetable oils (VOs) is another problem faced nowadays. The present study is focused on bio-based oils and many eco-friendly additives. Various machining processes and comparisons relating to the same have also been made. The aim is to minimize the use of mineral oil and thereby introduce sustainability in production.

In this present study, bio-based oils, additives and various characteristic behavior of them in machining are being discussed. The VOs are found to be a potential base oil for industrial CFs.

This paper describes the importance of sustainable CFs.

This paper aims to focus on the application of multi-attribute decision-making methods (MADMs) to ascertain the optimal machining parameters while turning Ti-6Al-4V alloy under minimum quantity lubrication (MQL) conditions using Jatropha-curcas oil (JCO) bio-based lubricant.

The experiments were designed and performed using Taguchi L27 design of experiments methodology. A total of 27 experiments were performed under MQL conditions using textured carbide cutting tools on which different MADMs like Analytic hierarchy process (AHP), Technique for order preference by similarity to ideal solution (TOPSIS) and Simple additive weighting (SAW) were implemented in an empirical manner to extract optimize machining parameters for turning of Ti-6Al-4V alloy under set of constrained conditions.

The results evaluated through MADMs exhibit the optimized set of machining parameters (cutting speed V_c = 80 m/min, feed rate f = 0.05 mm/rev. and depth of cut a_p = 0.10 mm) for minimizing the average surface roughness (Ra), maximum flank wear (Vbmax), tangential cutting force (Fc) and cutting temperature (T). Further, analysis of variance (ANOVA) and traditional desirability function approach was applied and results of TOPSIS and SAW methods having optimal setting of parameters were compared as well as confirmation experiments were conducted to verify the results. A SEM analysis at lowest and highest cutting speeds was performed to investigate the tool wear patterns. At the highest speed, large cutting temperature generated, thereby resulted in chipping as well as notching and fracturing of the textured insert.

The research paper attempted in exploring the optimized machining parameters during turning of difficult-to-cut titanium alloy (Ti-6AL-4V) with textured carbide cutting tool under MQL environment through combined approach of MADMs techniques. Ti-6Al-4V alloy has been extensively used in important aerospace components like fuselage, hydraulic tubing, bulk head, wing spar, landing gear, as well as bio-medical applications.

This study aims to investigate the effect of microtextured tools on the geometric morphology of serrated chips, and further improve the cutting performance of polycrystalline cubic boron nitride (PCBN) tool and extend the tool life and the surface quality of the machined surface.

A three-dimensional finite element cutting model of hardened steel AISI D2 with microtextured PCBN tools were established using the finite element software Abaqus, and cutting tests were carried out. Furthermore, the stress distribution in the primary deformation zone was investigated based on the triaxiality of stress, and the influence of microtexture on the geometric morphology of serrated chips and crack development was researched.

The results show that compared with nontexture tools, elliptical pits and wavy grooves microtexture tools have lower serrated degree Gs, higher serrated frequency f per unit length and more miniature serrated step Pc. The serrated phenomenon is intensified because the tensile stress zone of chips generated by nontextured tools is longer than that of elliptic pits and wavy grooves microtexture tools. Simultaneously, the maximum value of triaxiality in the tensile stress zone achieved by nontexture tools is larger than that of the two microtexture tools, and chips obtained by nontextured tools are more susceptible to propagation fractures.

This paper mainly studies the effect of microtexture on chip microgeometry, which is relatively little studied at present. At the same time, this paper has a certain engineering significance for PCBN tool turning hardening steel.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2023-0149/

The objective of this research is focused on the design of a new hybrid composite as well as to analyse the optimum turning conditions to minimise the surface roughness and work piece surface temperature, thereby increasing the productivity.

Mechanical properties such as hardness and tensile strength of Al-Si10Mg alloy reinforced with 3, 6 and 9 wt.% of alumina along with 3 wt.% of graphite prepared by stir casting method have been evaluated. The present study addresses the machinability parameter optimisation of Al alloy-9 per cent alumina-3 per centgraphite. Experiments were conducted based on the Taguchi parameter design by varying the feed (0.1, 0.15 and 0.2 mm/rev), cutting speed (200, 250 and 300 m/min) and depth of cut (0.5, 1.0 and 1.5 mm). The results were then analysed using analysis of variance (ANOVA).

Mechanical properties of the hybrid composite increases with reinforcement content. The surface roughness decreases with increasing cutting speed and conversely increases with increasing feed and depth of cut. The work piece surface temperature increases as cutting speed, feed and depth of cut increases. The ANOVA result reveals that feed plays a major role in minimising both surface roughness and surface temperature of work piece. The cutting speed and depth of cut follow feed in the order of importance, respectively.

The vibration of the machine tool is a factor which may contribute to poor quality characteristics. This factor has not taken been into account in this analysis since major vibrations in the machine are induced due to the machining process.

Design and development of new hybrid metal matrix composites (HMMCs) with a detailed analysis on machining conditions. The findings could help in the production of composite with a higher degree of surface finish. This will enable the adoption of HMMCs as industrial product for mass scale production.

Good quality characteristics were achieved using optimum machining conditions arrived using a statistical modelling.

The explicit finite element method (FEM) is one of the most popular approaches in quasi-static contact analysis which involves highly nonlinear friction and large deformation. Usually, a high loading rate is expected to improve computation efficiency in FEM. However, a higher loading rate often results in significant dynamic effects in the simulations. This study aims to propose a new criterion to achieve a good balance between a high loading rate and minimal dynamic effects.

The proposed criterion is based on the fluctuation of total strain energy as well as the smoothness of its first derivative to determine the proper loading time with an acceptable level of dynamic effect.

Asperities’ sliding contact and Hertz contact problems have been solved with the proposed criterion to verify its validity. The simulations show that the computation efficiency with the proposed criterion can be improved by up to 80 per cent compared to the regular energy ratio criterion.

This criterion will provide a valuable tool in determining the proper loading time to improve the computation efficiency for quasi-static analysis of asperities’ contacts.

The transistor circuit based on Moore's Law is approaching the performance limit. The three-dimensional integrated circuit (3-D IC) is an important way to implement More than Moore. The main problems in the development of 3-D IC are Joule heating and stress. The stresses and strains generated in 3-D ICs will affect the performance of electronic products, leading to various reliability issues. The intermetallic compound (IMC) joint materials and structures are the main factors affecting 3-D IC stress. The purpose of this paper is to optimize the design of the 3-D IC.

To optimize the design of 3-D IC, the numerical model of 3-D IC was established. The Taguchi experiment was designed to simulate the influence of IMC joint material, solder joint array and package size on 3-D IC stress.

The simulation results show that the solder joint array and IMC joint materials have great influence on the equivalent stress. Compared with the original design, the von Mises stress of the optimal design was reduced by 69.96 per cent, the signal-to-noise ratio (S/N) was increased by 10.46 dB and the fatigue life of the Sn-3.9Ag-0.6Cu solder joint was increased from 415 to 533 cycles, indicating that the reliability of the 3-D IC has been significantly improved.

It is necessary to study the material properties of the bonded structure since 3-D IC is a new packaging structure. Currently, there is no relevant research on the optimization design of solder joint array in 3-D IC. Therefore, the IMC joint material, the solder joint array, the chip thickness and the substrate thickness are selected as the control factors to analyze the influence of various factors on the 3-D IC stress and design. The orthogonal experiment is used to optimize the structure of the 3-D IC.

The wax deposition in oil wells and pipelines is very viciously negative to the petroleum extraction and crude oil transportation, and it even causes severe blockage accident. This study aims to describe cleaning experiments performed on wax deposition of different deposition layer and experimental conditions to investigate the removal and tribological properties and chip formation.

An optical arrangement was used to visually record the cleaning process, whereas the friction forces were measured by a custom-built tribometer. Various measurements were performed with tool rake angles of 45° and −30° and cleaning depths from 1 to 5 mm.

Results from experiments and modeling suggest that the transition of chip was dependent on rake angle, wax performance and cleaning depth. While the cleaning depth increased, the friction and cleaning resistant force also increased. With the increase of cleaning depth, the wax layer cleaning quantity increased and the chip strengthened; hence, the curvature radius of chip was enhanced to form platy chip. The chip of wax–oil mixture was discontinuous units, and it was easy to adhere on the rake face with the increasing depth of cut. With an increase in cleaning depth, the friction and cleaning-resistant force also increased.

It is concluded that for effectively cleaning and stabilizing of pipeline cleaning machine, different cleaning parameters should be applied to accommodate wax layer or wax–oil mixture.