scholarly journals Surface Layer States of Worn Uncoated and TiN-Coated WC/Co-Cemented Carbide Cutting Tools after Dry Plain Turning of Carbon Steel

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Johannes Kümmel ◽  
Katja Poser ◽  
Frederik Zanger ◽  
Jürgen Michna ◽  
Volker Schulze

Analyzing wear mechanisms and developments of surface layers in WC/Co-cemented carbide cutting inserts is of great importance for metal-cutting manufacturing. By knowing relevant processes within the surface layers of cutting tools during machining the choice of machining parameters can be influenced to get less wear and high tool life of the cutting tool. Tool wear obviously influences tool life and surface integrity of the workpiece (residual stresses, surface quality, work hardening, etc.), so the choice of optimised process parameters is of great relevance. Vapour-deposited coatings on WC/Co-cemented carbide cutting inserts are known to improve machining performance and tool life, but the mechanisms behind these improvements are not fully understood. The interaction between commercial TiN-coated and uncoated WC/Co-cemented carbide cutting inserts and a normalised SAE 1045 steel workpiece was investigated during a dry plain turning operation with constant material removal under varied machining parameters. Tool wear was assessed by light-optical microscopy, scanning electron microscopy (SEM), and EDX analysis. The state of surface layer was investigated by metallographic sectioning. Microstructural changes and material transfer due to tribological processes in the cutting zone were examined by SEM and EDX analyses.

1979 ◽  
Vol 101 (2) ◽  
pp. 185-190 ◽  
Author(s):  
K. Hitomi ◽  
N. Nakamura ◽  
S. Inoue

This paper is concerned with the reliability analysis of tool life based on the tool-wear values obtained from metal cutting experiments. From experimental results, a statistical distribution of tool wear was decided, and the distribution of tool life and the reliability function of cutting tools were derived. Further, it was shown that the reliability of cutting tools at a certain time was easily calculated from machining parameters and tool-wear limits by the use of reliability function.


2015 ◽  
Vol 770 ◽  
pp. 144-150
Author(s):  
V.E. Ovcharenko ◽  
Yuriy F. Ivanov ◽  
A.A. Mohovikov ◽  
A.S. Ignatyev ◽  
Yu Baohai ◽  
...  

A comparative analysis of the surface-layer microstructure of a tungsten-based cermet alloy modified with pulsed high-energy electron beams generated by gas-discharge plasmas and of the tool life of metal-cutting plates prepared from this alloy is performed. The choice of a plasma-forming gas providing for the emission of electrons out of the plasma-filled cathode is shown to have a profound influence both on the formation process of nanosized structural-phase states in the surface layer of the cermet alloy and on the tool life of the metal-cutting plates prepared from this alloy.


2021 ◽  
Author(s):  
Mourad NOUIOUA ◽  
Mohamed Lamine BOUHALAIS

Abstract In machining processes various phenomena occur during cutting operation. These phenomena can disturb the production through the reduction of part quality and accuracy. Therefore, a mastery of this cutting phenomena is needed to define the machining parameters and take full advantage of manufacturing process. An easy way to classify these phenomena is by monitoring incontrollable parameters, such as generated temperature and vibration. The acquired vibration signals can provide information regarding tool life, cutting performances and workpiece defects. This paper evaluates the possibility of monitoring the tool life during the turning process of AISI 1045 steel using Laser Doppler Vibrometer (LDV), the surface roughness has been measured along with the tool-wear until reaching its limit value of 300µm. Furthermore, this paper also outlines the application of CEEMDAN technique to process the acquired signals for the monitoring processes. RMS and SCI indicators have been used to describe the wear progress, then, the artificial neural network has been adopted to achieve a real time wear monitoring. The obtained results qualified the SCI indicator and ANN for online monitoring.


Materials ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2467 ◽  
Author(s):  
Szymon Wojciechowski ◽  
Rafał Talar ◽  
Paweł Zawadzki ◽  
Stanisław Legutko ◽  
Radosław Maruda ◽  
...  

The WCCo/PCD (Diamond Dispersed Cemented Carbide—DDCC) manufactured with the use of PPS (pulse plasma sintering) are modern materials intended for cutting tools with the benefits of tungsten carbides and polycrystalline diamonds. Nevertheless, the cutting performance of DDCC materials are currently not recognized. Thus this study proposes the evaluation of technological effects of a precise groove turning process of hard-to-cut AlSi13MgCuNi alloy with DDCC tools. The conducted studies involved the measurements of machined surface topographies after grooving with different cutting parameters. In addition, the tool life and wear tests of DDCC inserts were conducted during grooving process and the obtained results were compiled with values reached during machining with cemented carbide tools. It was also proved that grooving of AlSi13MgCuNi alloy with DDCC inserts enables 5 times longer tool life and almost 3-fold increase of cutting path compared to values obtained during grooving with H3 and H10 cemented carbide inserts. Ultimately, the feed value of f = 0.15 mm/rev and cutting speed in a range of 800 m/min ≤ vc ≤ 1000 m/min during grooving with DDCC inserts can be defined as an optimal machining parameters, enabling the maximization of tool life and improvement in surface quality.


2013 ◽  
Vol 456 ◽  
pp. 507-511
Author(s):  
Jian Bing Cheng ◽  
Si Qin Pang ◽  
Xi Bin Wang ◽  
Qi Xun Yu

Tool life tests of continuous cutting superalloy GH2132 were carried out by WC/Co cemented carbide cutting inserts of different grain size and cobalt content, and flank surface wear morphology of the cutting inserts were observed by ZEISS continuous zoom stereo microscope and microphotograph system. The results show that grain size and cobalt content strongly influence the cutting tool life and tool wear, grain refinement and proper cobalt content are help to improve the tool life and the wear resistance of WC/Co cemented carbide. The wear mechanisms of different grain size and cobalt content of ultrafine cemented carbide tools were adhesion and notch, among them, adhesive was the main wear mechanism at higher cutting speeds.


Author(s):  
Mitsuru Hasegawa ◽  
Tatsuya Sugihara

Abstract In cutting of Ti-6Al-4V alloy, the cutting speed is limited since a high cutting temperature leads to severe tool wear and short tool life, resulting in poor production efficiency. On the other hand, some recent literature has reported that various beneficial effects can be provided by forming micro-textures on the tool surface in the metal cutting process. In this study, in order to achieve high-performance machining of Ti-6Al-4V, we first investigated the mechanism of the tool failure process for a cemented carbide cutting tool in high-speed turning of Ti-6Al-4V. Based on the results, cutting tools with micro textured surfaces were developed under the consideration of a cutting fluid action. A series of experiments showed that the textured rake face successfully decreases the cutting temperature, resulting in a significant suppression of both crater wear and flank wear. In addition, the temperature zone where the texture tool is effective in terms of the tool life in the Ti-6Al-4V cutting was discussed.


Coatings ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 623 ◽  
Author(s):  
Dervis Ozkan ◽  
Peter Panjan ◽  
Mustafa Sabri Gok ◽  
Abdullah Cahit Karaoglanli

Carbon fiber-reinforced polymers (CFRPs) have very good mechanical properties, such as extremely high tensile strength/weight ratios, tensile modulus/weight ratios, and high strengths. CFRP composites need to be machined with a suitable cutting tool; otherwise, the machining quality may be reduced, and failures often occur. However, as a result of the high hardness and low thermal conductivity of CFRPs, the cutting tools used in the milling process of these materials complete their lifetime in a short cycle, due to especially abrasive wear and related failure mechanisms. As a result of tool wear, some problems, such as delamination, fiber breakage, uncut fiber and thermal damage, emerge in CFRP composite under working conditions. As one of the main failure mechanisms emerging in the milling of CFRPs, delamination is primarily affected by the cutting tool material and geometry, machining parameters, and the dynamic loads arising during the machining process. Dynamic loads can lead to the breakage and/or wear of cutting tools in the milling of difficult-to-machine CFRPs. The present research was carried out to understand the influence of different machining parameters on tool abrasion, and the work piece damage mechanisms during CFRP milling are experimentally investigated. For this purpose, cutting tests were carried out using a (Physical Vapor Deposition) PVD-coated single layer TiAlN and TiN carbide tool, and the abrasion behavior of the coated tool was investigated under dry machining. To understand the wear process, scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS) was used. As a result of the experiments, it was determined that the hard and abrasive structure of the carbon fibers caused flank wear on TiAlN- and TiN-coated cutting tools. The best machining parameters in terms of the delamination damage of the CFRP composite were obtained at high cutting speeds and low feed rates. It was found that the higher wear values were observed at the TiAlN-coated tool, at the feed rate of 0.05 mm/tooth.


Metals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1338
Author(s):  
Lakshmanan Selvam ◽  
Pradeep Kumar Murugesan ◽  
Dhananchezian Mani ◽  
Yuvaraj Natarajan

Over the past decade, the focus of the metal cutting industry has been on the improvement of tool life for achieving higher productivity and better finish. Researchers are attempting to reduce tool failure in several ways such as modified coating characteristics of a cutting tool, conventional coolant, cryogenic coolant, and cryogenic treated insert. In this study, a single layer coating was made on cutting carbide inserts with newly determined thickness. Coating thickness, presence of coating materials, and coated insert hardness were observed. This investigation also dealt with the effect of machining parameters on the cutting force, surface finish, and tool wear when turning Ti-6Al-4V alloy without coating and Physical Vapor Deposition (PVD)-AlCrN coated carbide cutting inserts under cryogenic conditions. The experimental results showed that AlCrN-based coated tools with cryogenic conditions developed reduced tool wear and surface roughness on the machined surface, and cutting force reductions were observed when a comparison was made with the uncoated carbide insert. The best optimal parameters of a cutting speed (Vc) of 215 m/min, feed rate (f) of 0.102 mm/rev, and depth of cut (doc) of 0.5 mm are recommended for turning titanium alloy using the multi-response TOPSIS technique.


2013 ◽  
Vol 59 (Special Issue) ◽  
pp. S42-S48
Author(s):  
R. Drlička ◽  
J. Žarnovský ◽  
R. Mikuš ◽  
I. Kováč ◽  
M. Korenko

For the renovation and/or improvement of the surface properties of machine elements, hard facing is often used. Hard structures obtained in layers or by heat treatment achieve a hardness of up to 68 hardness (HRC) or even more. The grinding of these surfaces demands the use of processing fluids and causes sometimes changes in the surface layers structure. Hard turning can replace grinding when certain requirements are fulfilled, particularly tough machining system. Hard deposits of two weld-on materials on a sample of steel grade S235JRG1 have been turned using cemented carbide inserts with a TiAlN coating of PVD type. The surface roughness measurements along with the observation of insert wear have been conducted to find proper machining parameters and conditions for this application. Cutting inserts manufacturer guidelines for special application could be insufficient or even not provided. Besides that, it is necessary in the experiments to take into account and examine the cutting ceramics and cubic boron nitride (CBN)/polycrystalline cubic boron nitride (PCBN).


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