Papers by Keyword: Machining Tool

Abstract: The various excitation effects are affecting the machining tools during the machining process. Cutting speeds, cutting forces, chip-making manner, the stiffness of MTW (machine-tool-workpiece) system are predominant effects affecting the dynamics of MTW system and also influencing the machining process (roughness of the machined surface, tool wear, tool or workpiece damage, noise generated by the machining process, etc.). In many cases, to achieve of adequate dynamic properties of the tool, the change of modal properties (mode shapes, natural frequencies) of the body tool must be performed using structural modification. The main objective of this paper will be to formulate, analyse and evaluate the proposed methods and procedures for structural modifications of the tool, represented as a beam. A modification of modal properties by insertion of non-uniform cross-section reinforcing core into body tool is studied and the effect of material properties and geometrical parameters of core on modal properties is analysed. The applications of structural modifications of tool body are leading to better conditions in the cutting process.

Abstract: By choosing appropriate annealing temperature and annealing time, diffusion couples made of aluminum bronze and tool materials were prepared to simulate the diffusion and phase formation during the actual machining. These results were compared to those obtained from turning experiments. In agreement with results obtained from diffusion couple experiments, all turning experiments showed that major elements in both tool materials and workpiece diffused into their counterparts. The diffusion of C away from the tool will reduce the tool strength. It is helpful to use diffusion couple results to comprehend the diffusion effect in the actual turning process.

Abstract: Machining of modern materials requires high performance tools. More than 60% of metal cutting tools used are coated to limit abrasive wear. As the harder material known to man, diamond and consequently Chemical Vapour Deposited (CVD) diamond coatings allow to increase performances of tungsten carbide tools, i.e. tool life, machined surface quality, and to decrease costs. However, CVD diamond coated tools quality is very dependent on the surface preparation as much as the fabrication process parameters. This paper aims to discuss the influence of pretreatments before deposition, and thermal stresses induced by the cooling operation. Diamond deposition process is described emphasizing the role of every step and its function. Some numerical simulations of the residual stresses at the interface are presented, enlightening that tool geometry is an important factor while using a coating, and that tools must be designed for the diamond coating.

Abstract: This study deals with the construction of network system for the production site, for the purpose of networking the machine tools as a part of the whole system. The Tele-monitoring for transformation of monitored information was studied. From the point of view of monitoring, the recognition of abnormal is very important in reducing the burden of an operator or for long-time unmanned operations. We then propose a method for the detection of abnormal in cutting process by analyzing the cutting sounds using Fourier transform, filtering, correlation analysis and statistic treatment. For the checking of tool wearing progressing, an experiment was arranged for the recognition of the sounds from a worn tip in comparison with a new one. On the detection of tipping of the cutter, a new tip is used for a long-time cutting without tool exchanging. The change of worn width and related values were compared with the original standard. It was found that the detection of tipping is possible by continuously sampling the cutting sounds and monitoring their correlation.