A variety of cutting tool materials are used for the contact mode mechanical machining of components under extreme conditions of stress, temperature and/or corrosion, including operations such as drilling, milling turning and so on. These demanding conditions impose a seriously high strain rate (an order of magnitude higher than forming), and this limits the useful life of cutting tools, especially single-point cutting tools. Tungsten carbide is the most popularly used cutting tool material, and unfortunately its main ingredients of W and Co are at high risk in terms of material supply and are listed among critical raw materials (CRMs) for EU, for which sustainable use should be addressed. This paper highlights the evolution and the trend of use of CRMs) in cutting tools for mechanical machining through a timely review. The focus of this review and its motivation was driven by the four following themes: (i) the discussion of newly emerging hybrid machining processes offering performance enhancements and longevity in terms of tool life (laser and cryogenic incorporation); (ii) the development and synthesis of new CRM substitutes to minimise the use of tungsten; (iii) the improvement of the recycling of worn tools; and (iv) the accelerated use of modelling and simulation to design long-lasting tools in the Industry-4.0 framework, circular economy and cyber secure manufacturing. It may be noted that the scope of this paper is not to represent a completely exhaustive document concerning cutting tools for mechanical processing, but to raise awareness and pave the way for innovative thinking on the use of critical materials in mechanical processing tools with the aim of developing smart, timely control strategies and mitigation measures to suppress the use of CRMs.

The Critical Raw Materials in Cutting Tools for Machining Applications: A Review

Among the various types of metal matrix composites, SiC particle-reinforced aluminum matrix composites (SiCp/Al) are finding increasing applications in many industrial fields such as aerospace, automotive, and electronics. However, SiCp/Al composites are considered as difficult-to-cut materials due to the hard ceramic reinforcement, which causes severe machinability degradation by increasing cutting tool wear, cutting force, etc. To improve the machinability of SiCp/Al composites, many techniques including conventional and nonconventional machining processes have been employed. The purpose of this study is to evaluate the machining performance of SiCp/Al composites using conventional machining, i.e., turning, milling, drilling, and grinding, and using nonconventional machining, namely electrical discharge machining (EDM), powder mixed EDM, wire EDM, electrochemical machining, and newly developed high-efficiency machining technologies, e.g., blasting erosion arc machining. This research not only presents an overview of the machining aspects of SiCp/Al composites using various processing technologies but also establishes optimization parameters as reference of industry applications.

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A review on conventional and nonconventional machining of SiC particle-reinforced aluminium matrix composites

Analysis of morphological, microstructural, electrochemical and nano mechanical characteristics of TiCN coatings prepared under N2 gas flow rate by chemical vapour deposition (CVD) process at higher temperature

Crystallization of SiC and its effects on microstructure, hardness and toughness in TaC/SiC multilayer films

The roller burnishing tool is used in computer numerical control lathe to superfinish the turning process. The tool and workpiece materials considered are tungsten carbide (69 HRC) and EN-9 Grade Alloy Steel (10 HRC), respectively. The input parameters are burnishing force, feed, roller contact width and number of passes. The response surface methodology is used to develop a mathematical model and optimize the parameters for the surface characteristics (such as surface roughness and surface hardness). The optimum surface roughness and its surface hardness are 0.2 µm and 18 HRC, respectively. The surface roughness is reduced by 94.5% and hardness is improved by 41.7%. The contributing variable of each parameter is estimated using analysis of variance method. The morphology of the burnished surface is investigated using scanning electron microscope.

Optimization of roller burnishing process on EN-9 grade alloy steel using response surface methodology

Microstructure and mechanical properties of Ti (C, N) based cermets reinforced with different ceramic particles processed by spark plasma sintering

Metallurgical and mechanical characterization of TiCN/TiAlN and TiAlN/TiCN bilayer nitride coatings

Mechanical properties and microstructures of TiCN/nano-TiB2/TiN cermets prepared by spark plasma sintering

Burnishing avoids the need for super finishing operations after the conventional turning process, to enhance the surface quality. This paper deals with the surface modifications of Al(B4C)p Metal Matrix Composites (MMC) workpiece material after burnishing with a TiAlN coated WC roller. The burnishing speed, lubrication type, burnishing passes, and coating were the input parameters. Surface hardness and roughness after the burnishing were studied. It was found that the coating on the WC roller had enhanced the hardness in the workpiece after burnishing in the case of Al-5 wt.% (B4C)p, under all conditions. The effect of the coating on the work piece surface hardness was not significant with Al-10 wt.% (B4C)p. While burnishing Al-5 wt.% (B4C)p, the minimum surface roughness combined with maximum surface hardness was obtained, during the third pass under dry condition using uncoated rollers. The number of passes to achieve the desired surface conditions reduced, on using coated rollers with kerosene ...

Investigation of TiAlN coated roller burnishing on Al-(B4C)p MMC workpiece material

This paper reports the effect of tungsten carbide (WC) and cobalt (Co) addition on the microstructural and mechanical properties of titanium carbonitride (TiCN) cermets modified by Cr3C2 and nano-TiB2 addition, processed by spark plasma sintering (SPS). The addition of the WC and Co was varied from 0 to 15 wt%. The microstructure, hardness and fracture toughness of the developed cermets were studied. The hardness and fracture toughness of the cermets increased to 52% and 33%, respectively with WC additions. With Co additions the hardness decreased by 13%, but the fracture toughness increased by 9%. The cermet with 60%TiCN-15%WC-15%Co-5%Cr2C3-5% nano-TiB2 composition has shown balanced improvement in hardness (19.1 GPa) and toughness (8.4 MPa·m1/2). The machining performed by this cermet, developed minimum cutting force and surface roughness on the machined surface of the EN24 workpiece material.

Influence of WC and cobalt additions on the microstructural and mechanical properties of TiCN-Cr3C2-nano-TiB2 cermets fabricated by spark plasma sintering

E. Shankar

Papers

Microstructure and mechanical properties of Ti (C, N) based cermets reinforced with different ceramic particles processed by spark plasma sintering

Metallurgical and mechanical characterization of TiCN/TiAlN and TiAlN/TiCN bilayer nitride coatings

Mechanical properties and microstructures of TiCN/nano-TiB2/TiN cermets prepared by spark plasma sintering

Investigation of TiAlN coated roller burnishing on Al-(B4C)p MMC workpiece material

Influence of WC and cobalt additions on the microstructural and mechanical properties of TiCN-Cr3C2-nano-TiB2 cermets fabricated by spark plasma sintering