Papers by Keyword: Tool Wear

Abstract: The ZTA-TiO₂-Cr₂O₃ ceramic cutting tool is a new cutting tool that possesses good hardness and fracture toughness. Yet, the performance of the ZTA-TiO₂-Cr₂O₃ cutting tool is still unknown and needs further study. In this research, the comparison of the ZTA-TiO₂-Cr₂O₃ and Kennametal ceramic cutting tool is investigated. The turning process by using ZTA-TiO₂-Cr₂O₃ and Kennametal commercial ceramic cutting tools is performed on the Bridgeport ROMI PowerPath CNC lathe machine. The parameters utilized are spindle speed in the range of 907 to 1543 rpm, feed rate from 0.08 to 0.22 mm/rev, and depth of cut of 0.2 mm. Analysis of the flank wear and crater wear were performed by using an optical microscope (NIKON MM-4001L), while the chipping area was observed by scanning electron microscopy, SEM (JEOL JSM-IT100). The surface roughness of the machined surface is measured via portable surface roughness (Mahr MarSurf M3000C). The comparison between the cutting tool produced in this research and the commercial cutting tool shows that the wear performance of the ZTA-TiO₂-Cr₂O₃ ceramic cutting tool is lower than the Kennametal commercial ceramic cutting tool. Even though this newly fabricated cutting tool is far behind compared to the commercial cutting tool, it shows some promising aspects such as the ability to cut at a higher speed.

Abstract: Aluminium bronze alloys are special copper alloys that have a machinability rate from 20 to 40% compared to free cutting brasses, so the cutting parameters and type of tools suitable for machining of these materials may be very different for other copper alloys. Also, due to the relative high costs of the raw material, the absence of contamination of the chips by cutting fluids improve its intrinsic resales value and encourage the use of machining process without coolant. The aim of this work is to evaluate the tool wear mechanisms in the finishing machining of the Cu-10wt%Al-5wt%Ni-5wt%Fe aluminium-bronze alloy with carbide and cermet inserts at different cutting speeds under dry machining condition. The turning of material showed lower surface roughness in higher speed conditions and better dimensional stability at lower speeds. It was observed the formation of continuous chips, but of little volume occupied. The scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) analyses of tool wear show the adhesion as the main tool wear mechanism, followed by abrasion. At the lower cutting speed, the adhesion wears affected significantly the surface finish, reducing the tool life in comparison to the higher speeds.

Abstract: The main issue in machining glass fiber reinforced polymers is a rapid wearing of the cutting tool caused by the superior properties of the fiber reinforcement within the matrix. Cooling in machining processes reduces tool wear and extends tool life. Cryogenic cooling is an alternative method for effective, environmentally friendly, clean and safe cooling. This paper studied the tool wear characteristics of carbide inserts coated with TiCN and Al₂O₃ in turning glass fiber reinforced epoxy resin pipe. The cutting parameters were various, with cutting speed, feed rate, depth of cut and cutting conditions (without cooling and with cryogenic cooling). Not all cutting speeds that were cooled under cryogenics showed good outcomes. However, the experimental results suggest that using high cutting speed at 1800 rpm and high feed rate at 0.13 mm/rev, together with cryogenic cooling, can reduce the flank wear of the tool compared with no cooling.

Abstract: The heat generation and subsequent temperature rise in the cutting zone due to plastic deformation and friction at tool-chip-workpiece interface are critical parameters that have a significant impact on tool wear, tool life and surface integrity. This paper aimed to analyse the effect of cutting parameters such as, cutting speed, feed and depth of cut on the cutting temperature in turning of hardened AISI 52100 alloy steel of 58 HRC using multilayer coated carbide cutting tool insert under high velocity pulsing jet minimal cutting fluid application (MCFA) environment. Response surface methodology based central composite design (CCD) was used to investigate and optimize the cutting parameters on cutting temperature response. The quadratic regression model in terms of cutting speed, feed and depth of cut for cutting temperature was developed. The diagnostic and confirmatory tests were carried out to check its validity. The implication of the process parameters and their interactions were tested using analysis of variance (ANOVA). The results showed that the cutting speed and feed were the main significant parameters affecting the cutting temperature, while depth of cut and quadratic term of cutting speed had a moderate effect. The predictive model developed indicates the 99% desirability level in turning of AISI 52100 hardened steel under the MCFA environment. The predicted values of cutting temperature response are in close agreement with the experimental results.

Abstract: In cutting process, the wear of the tool remains posed, it describes their progressive failure in regular operation. The tool wear phenomena is mainly caused by abrasion of hard particles, shearing of micro welds between tool and work-material and the exchange of particles between the tool and work material leading to a several forms of tool wear, however, we focused in this study on the frontal wear, also called wear on clearance surface or flank wear. For efficient use of cutting tool according to the technical requirement, the comprehension and the knowledge of the cutting tool wear evolution is necessary. In order to meet this indispensable need, the present paper proposes a two-step tool flank wear monitoring technique based on vibratory signals analysis during the turning operation using a P30 grade metal carbide tool and C45 (XC48) steel. Firstly, discrete wavelet transforms (DWT), has been used to decompose the signal and extract the information, then the scalar indicator Root Mean Square (RMS) value has been used to evaluate the cutting tool stability level. The proposed method offers the possibility to accurately predict break-in tool wear phase, accelerated tool wear phase and the stability period, in which a high quality machining process is guaranteed.

Abstract: The high-performance machining of difficult-to-cut stainless steel (AISI 316) demands the development and optimization of high-performance tools that can withstand tool load without compromising the surface quality of the components been produced. To justify the optimization feasibility of coated carbide tool in end milling application for good surface quality, a material removal and Productivity approach by evaluating the tool life under optimized cutting condition were carried out in this current research. The objective of this study is to optimize flank tool wear in end milling of AISI 316 using Design of Experiment and box-Behnken method. Tool wear value of 0.174mm was achieved through optimization at low values of feed, speed, and depth of cut. However, an increased feed, depth of cut and speed promised to yield better volume removed in return making tool life to be truncated faster.

Abstract: Reaming is one of the finishing processes that has been widely applied in automotive industry. Reaming parameters were evaluated and optimized based on multiple performance characteristics including tool wear and hole quality. Taguchi’s L₁₆, 4-level, 2-factor orthogonal array (OA) was conducted for this test. It was shown that crater wear and flank wear were seen on the tool surface. Furthermore, the crater wear was also of major significance. Hole quality was discovered to be mostly dependent upon cutting speed and feed rate. TiAlN coated carbide reamer shows the best performance with respect to the tool wear as well as hole quality. Grey relational analysis used as a multiple-response optimization technique found that feed rate was the more influential parameter than cutting speed. The goal of the experimental results was to obtain both minimum diametral error and the value of surface roughness by adopting the optimal combination of the reaming parameters.

Abstract: Deep-hole machining is an important part in the field of mechanical processing of diesel engine. Gun drill has been widely used in deep-hole machining because of its high dimensional accuracy, high efficiency and good straightness. Through experiments on drilling compacted graphite iron with two different edge types of double-edged gun drills, the spindle power, axial force and tool wear were analyzed and found out one edge type which is more suitable for processing compacted graphite iron. This paper presents a simulation of deep hole drilling to validate the analysis. The research results have important guiding significance for deep hole processing of compacted graphite iron.

Abstract: This paper investigated the performance of ZTA cutting tool with the addition of different particle size of MgO additive. Therefore, the objective of this research is to compare the effects of machining parameters on tool wears of ZTA cutting tools added with micro and nanoparticle of MgO. The experiments were conducted using BridgePort-Romi Powerpath CNC machine using a tool holder Sandvik Coromant (CoroTurn CCLNR 164D-4) to hold the cutting tools properly. The parameters are set up as cutting speeds used between range 354 to 472 m/min, feed rate from 0.1 to 0.5 mm/rev with a constant depth of cut of 0.2 mm. Three types of wear were analyzed which are flank wear, crater wear and tool chipping. Flank wear and crater wear images captured using measuring microscope (NIKON MM-400/L) and the crater wear areas are analyzed using MatLab programming software. Tool chipping is observed via SEM (JEOL JSM-5600). The experimental result shows that flank wear and crater wear increase when cutting speed and feed rate increase. ZMN cutting tool shows lower value of flank wear at 0.143 mm and 3.741 mm² for crater wear than ZMM, 0.321 mm and 3.808 mm² respectively. On the contrary, cutting speed did not affect the tool chipping severely as feed rate. Moreover, ZMN also shows that the tool breakage occurred severely than ZMM due to the high load on the tool nose.

Abstract: One of the most significant factors in machining process or metal cutting is the cutting tool performance. The rapid wear rate of cutting tools and cutting forces expend due to high cutting temperature is a critical problem to be solved in high-speed machining process, milling. Near-dry machining such as minimum quantity lubrication (MQL) is regarded as one of the solutions to solve this problem. However, the function of MQL in milling process is still uncertain so far which prevents MQL from widely being utilized in this specific machining process. In this paper, the mechanism of cutting tool performance such as tool wear and cutting forces in MQL assisted milling is investigated more comprehensively and the results are compared in three different cutting conditions which is dry cutting, wet cutting (flooding) and MQL. The MQL applicator is constructed from a household grade low-cost 3D printing technique. The chips surface of chips formation in each cutting condition is also observed using Scanning Electron Microscopy (SEM) machine. It is found out that wet cutting (flooding) is the best cutting performance compare to MQL and dry cutting. However, it can also be said that wet cutting and MQL produced almost the same value of tool wear and cutting forces as there is negligible differences in average tool wear and cutting forces between them based on the experiment conducted.