【摘要】 对刀具涂层技术的发展现状与趋势进行了综述,提出了提高涂层刀具性能的"五化"措施:沉积工艺复合化、薄膜组成多元化、薄膜结构多层化、薄膜组成和显微结构梯度化、薄膜晶粒纳米化。基于这个思想,提出了用高能量密度脉冲等离子体技术进行陶瓷刀具表面改性,并在最近几年用高能量密度脉冲等离子体同轴枪对硬质合金和氮化硅陶瓷刀具进行了镀膜改性尝试。使用该复合表面改性技术,所制备涂层刀具结构独特,很好地满足了"五化"思想,材料性能得到显著提高。在优化的工艺条件下,所得TiN、TiCN和TiAlN涂层刀具硬度高,纳米硬度分别为26～28GPa、50～53GPa和38～40GPa;膜基结合力强,纳米划痕临界载荷达80～110mN。所得TiN、TiCN和(Ti,Al)N涂层硬质合金刀具能够在工业条件下对硬度高达HRC58～62的淬硬CrWMn钢进行干切削,实用切削速度可提高2～10倍,且刀具磨损较小;涂层氮化硅陶瓷刀具加工淬硬钢和灰铸铁(HB2200～2300MPa)工件时,比未涂层刀具后面磨损降低6～10倍。预示该技术是一种非常有前途的陶瓷刀具改性技术。更多还原

【Abstract】 The progress of surface modification techniques for cutting tools was reviewed in this article. It was proposed that the performances of coated tools would be improved by the below methods,i.e composite deposition technique,multicomponent coating,multilayered coating structure,graded structures of coating composition and microstructures,and nanosized coating grains. It is well consistent with this idea using pulsed high energy density plasma (PHEDP) for the surface modification of ceramic cutting tools. With PHEDP,at room temperature,TiN,TiCN,and (Ti,Al)N coatings were deposited on WC-Co cermet and silicon nitride ceramic cutting tools. And under optimum deposition conditions,the nanohardness of TiN-,TiCN-,and (Ti,Al)N-coated cutting tools reached 26～28 GPa,50～53 GPa and 38～40 GPa,respectively; and the adhesion strengths of these coatings to tool substrates were high with critical loads in nanoscratch tests being 80～110 mN. Under industrial conditions,the obtained coated WC-Co cemented cutting tools can be applied for turning of hardened CrWMn steel (HRC 58-62) with improved cutting speed increased by 2～10 times,and the coated silicon nitride ceramic tools can be applied in turning of hardened CrWMn steel and grey iron (HB 2200～2300 MPa) with better wear performance improved by 6～10 times. This means that PHEDP is a promising technique for the surface modification of ceramic cutting tools.更多还原