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The purpose of this paper is to study the influence of the cutting conditions (cutting speed, feed rate and cutting depth) on the roughness (Ra) and on the flank wear (Vb) of the steel AISI 4140.

Mixed ceramic (CC650) and polycrystalline cubic boron nitride (PCBN) have been used to carry out straight turning tests under dry conditions.

The results indicate that PCBN is more efficient than mixed ceramic (Al2O3+TiC) used in terms of wear resistance regardless of the aggressiveness of the AISI 4140 at 50 hardness rockwell (HRC). Consequently, it is the most powerful. Surface quality attained with PCBN tool considerably compares with that of grinding. Even when the tool wear VB reached 0.3 mm, the majority of the recorded Ra values did not exceed 1 m at the various speeds tested. The correlation of tool wear Vb and surface roughness Ra established allows obtaining experimental empirical data on the cutting tool wear from measured surface roughness for practical use in industry. The values of constants and the coefficient of determination R² of this mathematical model will be calculated. Mathematical models expressing the relation between the elements of the cutting regime and technological parameters (tool life and roughness) are proposed.

Many works have been already made in the similar manner, but this study of CC650 and PCBN wear is the first. Through this study, we propose a mathematical model expressing the relation between the elements of the cutting regime, tool life and roughness.

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/

This paper gives the background to the measurement of metal cutting temperatures and a review of the practicality of the various methods of measuring cutting temperature while machining metals.

The review was compiled after a literature search, visits to other research establishments and discussions with other researchers in the machining/temperature measurement field.

Information about several methods of measuring cutting temperature during a machining process is given along with the limitations of the use of each method.

All the temperature measurement methods discussed have their limitations and these are described for each method listed.

The paper provides a review of all the cutting temperature measurement methods discovered in recent work. This will be a reference document of interest to others working in this field.

The purpose of this paper is to outline and document the failure root cause of a carbide cutting tool during machining of a hardened tool steel under automatic machining conditions.

Optical metallography and SEM/energy dispersive spectroscopy analysis, together with optical profilometry were employed for failure investigation. The use of an alternative cutting tool and modification of machining conditions are proposed as a failure preventive action.

Severe abrasive wear and adhesion of machining chips are observed in the flank zone, causing blunting of the cutting edge. The revision of cutting conditions, together with the use CBN-based tool insert leads to an overall improvement of the stability of the process and tool lifetime.

This paper places emphasis on a failure analysis case history following a structured approach in industrial machining problem solving, highlighting suggestions for process improvement.

The purpose of this paper is to propose a methodology to estimate manufacturing complexity for both machining and layered manufacturing. The goal is to take into account manufacturing constraints at design stage in order to realize tools (dies and molds) by a combination of a subtractive process (high‐speed machining) and an additive process (selective laser sintering).

Manufacturability indexes are defined and calculated from the tool computer‐aided design (CAD) model, according to geometric, material and specification information. The indexes are divided into two categories: global and local. For local indexes, a decomposition of the tool CAD model is used, based on an octree decomposition algorithm and a map of manufacturing complexity is obtained.

The manufacturability indexes values provide a well‐detailed view of which areas of the tool may advantageously be machined or manufactured by an additive process.

Nowadays, layered manufacturing processes are coming to maturity, but there is still no way to compare these new processes with traditional ones (like machining) at the early design stage. In this paper, a new methodology is proposed to combine additive and subtractive processes, for tooling design and manufacturing. A manufacturability analysis is based on an octree decomposition, with calculation of manufacturing complexity indexes from the tool CAD model.

The purpose of this study to analyze the plastic anisotropy of 6061 aluminum alloy with finite deformation using crystal plasticity finite element method.

A representative volume element (RVE) model was constructed by Voronoi tessellation. In this model, grain shapes, grain orientations and distribution of grains were involved. The mechanical response of the component under composite loading was tested using specify cruciform specimen. Moreover, different stress and strain states in the specific central region were analyzed to reveal the effects of complex loading.

We calculated the influence of misorientation of adjacent grains as well as the evolution of the micro structure’s plastic deformation on the macroscopic deformation of the structure. Geometry design for the cruciform specimen helps obtain a homogenous distribution of the stress and strain at the specimen center. In this process, the initial grain orientation is also an important factor, and the larger misorientations between special grains may cause greater stress concentration.

The influence of micro-scale factors on macro-scale plastic anisotropy of AA6061 is analyzed using RVE model and cruciform specimen, and they offer a reference for related research.

The purpose of this paper is to provide a practical review of the use of the minimum quantity lubrication (MQL) system in turning operations, focussing on the application of the technique in the turning of different kind of materials.

The use of the MQL system was analysed by several researchers in the past years. Thus, in the present paper, a relevant sample of the main experimental studies that can be found in the literature was analysed to come up with a review with relevant information for researchers and industry.

The use of the MQL system can help to improve the outcomes of the turning process in several issues like surface quality or tool life. However, it was also recognised that in some cases, other cooling/lubricating methods can provide better results than the MQL system. Thus, the decision, whether to use or not the MQL system in a specific process, is of great importance.

The work is conveniently focussed to serve as a quick reference on the issue. At the same time, the work analysed the use of the turning of some of the main engineering materials that makes it useful for a wider range of researchers and metalworking firms. Finally, the review could be useful to improve the performance of the industry, especially for the metalworking firms in terms of costs, environmental impact and safety.

The purpose of the present paper aims to, study the coefficient of friction and wear behavior of nickel based super alloys used in manufacturing of gas and steam turbine blades. In present paper, parametric study focuses on normal load, dry sliding velocity and contact temperature influence on coefficient of friction and wear of a nickel based super alloy material.

Experimental investigation is carried out to know the effect of varying load at constant sliding velocity and varying sliding velocity at constant load on coefficient of friction and wear behavior of nickel based super alloy material. The experiments are carried out on a nickel based super alloy material using pin on disk apparatus by load ranging from 30 N to 90 N and sliding velocity from 1.34 m/s to 2.67 m/s. The contact temperature between pin and disk is measured using K-type thermocouple for all test conditions to know effect of contact temperature on coefficient of friction and wear behavior of nickel based super alloy material. Analytical calculations are carried out to find wear rate and wear coefficient of the test specimen and are compared with experimental results for validation of experimental setup. Regression equations are generated from experimental results to estimate coefficient of friction and wear in the range of test conditions.

From the experimental results, it is observed that by increasing the normal load or sliding velocity, the contact temperature between the pin and disk increases, the coefficient of friction decreases and wear increases. Analysis of variance (ANOVA) is used to study the influence of individual parameters like normal load, dry sliding speed and sliding distance on the coefficient of friction and wear of nickel based super alloy material.

This is the first time to study effect of contact temperature on the coefficient of friction and wear behavior of nickel-based super alloy used for gas and steam turbine blades. Separate regression equations have been developed to determine the coefficient of friction and wear for the entire range of speed of gas turbine blades made of nickel based super alloy. The regression equations are also validated against experimental results.

The purpose of this paper is to study the microstructure and the high-temperature tribology behavior of a high-speed steel (HSS) roller material with boron as the main alloy element under different heat treatments, aiming to provide some theoretical references for its engineering application.

The samples of high boron HSS were quenched at 900°C, 1,000°C, 1,050°C and 1,150°C. The microstructure, composition and phase composition of this new HSS were analyzed by OM, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray diffractometer. The surface hardness and the tribology behavior under high temperature were measured by Rockwell hardness tester and the high-temperature friction and wear tester. The wear morphology was observed by SEM.

The high-temperature friction coefficient and the relative wear rate of the high boron HSS decrease first, then increase with the rise of the quenching temperature. When the quenching temperature is 1,050°C, both the friction coefficient (0.425) and the relative wear rate (79 per cent) are the smallest. Under the high-temperature friction environment, the high boron HSS mainly includes oxidation wear, adhesive wear and abrasive wear. The effect of abrasive wear is weakened gradually with the rise of the quenching temperature, and the high-temperature wear resistance is improved significantly. Compared with the traditional roll materials, the service life of the new high boron HSS is greatly improved. It is an ideal substitute product for the high chromium cast iron roll.

The boron element replaces other precious metals in high boron HSS, which has the advantage of low production cost, and it has a wide application in the field of roll materials. In this paper, the microstructure, the transformation of hard phases and the high-temperature tribology behavior of this new high boron HSS under different heat treatments were studied, aiming to provide some theoretical references for its engineering application.

The purpose of this paper is to compile a comprehensive status report on pipes/piping networks across different industrial sectors, along with specifications of materials and sizes, and showcase welding avenues. It further extends to highlight the promising friction stir welding as a single solid-state pipe welding procedure. This paper will enable all piping, welding and friction stir welding stakeholders to identify scope for their engagement in a single window.

The paper is a review paper, and it is mainly structured around sections on materials, sizes and standards for pipes in different sectors and the current welding practice for joining pipe and pipe connections; on the process and principle of friction stir welding (FSW) for pipes; identification of main welding process parameters for the FSW of pipes; effects of process parameters; and a well-carved-out concluding summary.

A well-carved-out concluding summary of extracts from thoroughly studied research is presented in a structured way in which the avenues for the engagement of FSW are identified.

The implications of the research are far-reaching. The FSW is currently expanding very fast in the welding of flat surfaces and has evolved into a vast number of variants because of its advantages and versatility. The application of FSW is coming up late but catching up fast, and as a late starter, the outcomes of such a review paper may support stake holders to expand the application of this process from pipe welding to pipe manufacturing, cladding and other high-end applications. Because the process is inherently inclined towards automation, its throughput rate is high and it does not need any consumables, the ultimate benefit can be passed on to the industry in terms of financial gains.

To the best of the authors’ knowledge, this is the only review exclusively for the friction stir welding of pipes with a well-organized piping specification detailed about industrial sectors. The current pipe welding practice in each sector has been presented, and the avenues for engaging FSW have been highlighted. The FSW pipe process parameters are characteristically distinguished from the conventional FSW, and the effects of the process parameters have been presented. The summary is concise yet comprehensive and organized in a structured manner.