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Cutting Tools (cutting + tool)
Selected AbstractsAnalyses of the Performance Potential of Oxidic PVD Wear-Protection Coatings on Cutting Tools Using the Example of Crystalline ,-Al2O3,ADVANCED ENGINEERING MATERIALS, Issue 7 2008F. Klocke This paper focuses on the high performance potential of oxidic PVD coatings on cutting tools using the example of crystalline ,-Al2O3. The materials used during the cutting processes were the nickel-based alloy, Inconel 718, in wet-cut drilling and milling as well as a quenched and tempered steel in dry-cut milling. The conclusion that may be drawn from these analyses is that oxidic PVD coatings are characterised by outstanding wear behaviour and can contribute to a significant increase in cutting performance. [source] Al2O3/TiC Based Metal Cutting Tools by Microwave Sintering Followed by Hot Isostatic PressingJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2000Adrian Goldstein The feasibility of producing Al2O3/TiC metal cutting tools by fast microwave sintering followed by hot isostatic pressing was examined. Microwave heating profiles able to ensure near-full densification of Al2O3/TiC ceramic components were determined. Simple-shape specimens could be sintered to a bulk density of 97% theoretical density (TD) while in the case of tool-shaped ones maximal densification levels attained were somewhat lower, i.e., ,95% TD. Temperature uniformization,within the heating chamber,by using a particulate SiC susceptor noticeably reduced tool cracking propensity. Densification levels in the range acceptable for commercial tool manufacturing (,98% TD) were achieved by hot isostatic pressing of the microwave-sintered parts. The isostatically pressed parts exhibited a Vickers hardness Hv, 2000 kg/mm2 and a fracture toughness KIC, 4.3 MPa·m1/2. [source] New tribometer designed for the characterisation of the friction properties at the tool/chip/workpiece interfaces in machiningLUBRICATION SCIENCE, Issue 1 2008F. Zemzemi Abstract This work deals with the development of a new tribometer designed for the characterisation of the frictional properties at the tool/chip/workpiece interfaces in cutting processes. Based on a plane,sphere contact configuration, the experimental set-up enables a continuous regeneration of the pin,workmaterial contact. The average contact pressure can be selected up to 3,GPa under sliding velocities reaching 16,m/s. Under such severe conditions, which are not reachable with conventional tribometers, the apparent friction coefficient is quantified in parallel to the heat flux transmitted to the pin. This new system has been applied to the characterisation of the frictional properties during the dry machining of a 27MnCr5 annealed steel with a carbide cutting tool. The influence of the sliding velocity and of an additional TiN layer deposited by PVD on the carbide pins has been investigated in dry conditions. It has been shown that the sliding velocity is the more influential parameter, followed by the coating. Copyright © 2007 John Wiley & Sons, Ltd. [source] Effect of Microstructure on Residual Stresses in Sintered Diamond,Metal Composites,ADVANCED ENGINEERING MATERIALS, Issue 6 2009U. Selvadurai-Laßl As residual stresses can reduce the lifetime of diamond-cobalt composite cutting tools, the composite stress state needs to be understood very well. Thus, the effect of microstructure on the residual stresses was investigated here. Stress measurements were carried out in the cobalt matrix by X-ray diffraction (XRD) and Synchrotron-XRD (SXRD). In addition to global stress measurements, investigations of stresses in small cobalt areas near the diamonds were performed by high brilliant synchrotron radiation using different apertures. [source] Analyses of the Performance Potential of Oxidic PVD Wear-Protection Coatings on Cutting Tools Using the Example of Crystalline ,-Al2O3,ADVANCED ENGINEERING MATERIALS, Issue 7 2008F. Klocke This paper focuses on the high performance potential of oxidic PVD coatings on cutting tools using the example of crystalline ,-Al2O3. The materials used during the cutting processes were the nickel-based alloy, Inconel 718, in wet-cut drilling and milling as well as a quenched and tempered steel in dry-cut milling. The conclusion that may be drawn from these analyses is that oxidic PVD coatings are characterised by outstanding wear behaviour and can contribute to a significant increase in cutting performance. [source] Influence of Surface Modification on the Cutting Performance of Reaction-Sintered Al2O3,TiOC CeramicsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2008Anup K. Bhattacharya Al2O3,TiC mixed ceramics are popular for dry cutting of hardened steel. In this work, the cutting performance of surface-modified mixed ceramic cutting tools has been studied. A 1-,m-thick modified surface has been obtained by CO2 posttreatment of the Al2O3,TiOC mixed ceramics. The cutting performance of the modified tools has been found to be much better than the precursor-mixed ceramics. The density of the modified layer also has an influence on the cutting performance. Modified ceramics with a dense surface layer show considerably improved wear resistance compared with that of ceramics with a porous layer. While plastic deformation of the TiC layer in the flank surface, followed by abrasive wear of the exposed substrate is responsible for flank wear, crater wear is caused mainly by diffusion reaction as well as by abrasion. In our system, it is mainly the flank wear that controls the cutting performance of the inserts. [source] Al2O3/TiC Based Metal Cutting Tools by Microwave Sintering Followed by Hot Isostatic PressingJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2000Adrian Goldstein The feasibility of producing Al2O3/TiC metal cutting tools by fast microwave sintering followed by hot isostatic pressing was examined. Microwave heating profiles able to ensure near-full densification of Al2O3/TiC ceramic components were determined. Simple-shape specimens could be sintered to a bulk density of 97% theoretical density (TD) while in the case of tool-shaped ones maximal densification levels attained were somewhat lower, i.e., ,95% TD. Temperature uniformization,within the heating chamber,by using a particulate SiC susceptor noticeably reduced tool cracking propensity. Densification levels in the range acceptable for commercial tool manufacturing (,98% TD) were achieved by hot isostatic pressing of the microwave-sintered parts. The isostatically pressed parts exhibited a Vickers hardness Hv, 2000 kg/mm2 and a fracture toughness KIC, 4.3 MPa·m1/2. [source] Pulsed Nanocomposite TiAlN Coatings on Complex Shaped Tools for High Performance Cutting OperationsPLASMA PROCESSES AND POLYMERS, Issue S1 2007Kirsten Bobzin Abstract The demand on high profitability in cutting operations has led to a variety of requirements for high performance tool coatings. Nanostructured coatings have shown most promising results in this connection. High oxidation resistance, hot hardness, and loW friction are just a few benefits that these coatings offer. The deposition of nanostructured coatings is only possible within a small deposition process window. Most cutting tool surfaces are complex shaped and include, for instance, small corner radii at the cutting edge or chip breakers. The local process window and the deposition parameters must be adapted to the actual shape of the cutting tools in order to obtain a hard nanocomposite coating with adequate adhesion properties. Finally, the performance of these coatings has been studied in machining tests. [source] | ||||||||||