Title: Cutting performance and wear characteristics of Al2O3/TiC/CaF2 ceramic tools in dry cutting of hardened steel
Authors: Deng Jianxin, Zhao Jinlong, Wu Fengfang
Addresses: School of Mechanical Engineering, Shandong University, Jinan 250061, Shandong Province, PR China. ' School of Mechanical Engineering, Shandong University, Jinan 250061, Shandong Province, PR China. ' School of Mechanical Engineering, Shandong University, Jinan 250061, Shandong Province, PR China
Abstract: Al2O3/TiC ceramic cutting tools with the additions of CaF2 solid lubricants were produced by hot pressing. Dry machining tests were carried out on hardened steel. The tool wear, the cutting forces and the friction coefficient between the tool–chip interface were measured. It was shown that the crater wear of Al2O3/TiC/CaF2 tools were reduced compared with that of Al2O3/TiC tools under the same test conditions. The mechanism responsible was explained as the formation of a self-lubricating film on the tool–chip interface under high cutting speed conditions. The appearance of this self-lubricating film contributed to the decrease of the friction coefficient at the tool–chip interface. Cutting speed was found to have a profound effect on the friction coefficient. The additions of CaF2 solid lubricant to Al2O3/TiC led to an increase in flank wear. This may be attributed to the degradation of mechanical properties compared with Al2O3/TiC tools. Microstructure analysis of the wear surface showed the self-lubricating film on the tool rake face experiences a four-stage cycle, that is, forming, fracture, falling off and reforming. Therefore, this kind of ceramic tool has self-lubricating behaviours during its full lifetime.
Keywords: ceramic tools; cutting performance; self-lubricating; solid lubricants; tool wear; wear characteristics; dry cutting; dry machining; hardened steel; pressing; cutting forces; friction coefficient; tool–chip interface; crater wear; cutting speed; flank wear; microstructure analysis.
International Journal of Machining and Machinability of Materials, 2006 Vol.1 No.3, pp.301 - 312
Published online: 24 Nov 2006 *Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article