梯度功能陶瓷刀具材料的残余应力设计及制备

RESIDUAL STRESS DESIGN AND FABRICATION OF FUNCTIONALLY GRADIENTCERAMIC TOOL MATERIALS

根据陶瓷刀具切削时刀楔内的应力分布规律及刀具损坏机理的分析，首次提出对陶瓷刀具材料的组成分布进行设计以形成梯度的模型．通过对不同组成分布的刀具材料制备过程中的残余热应力及刀具切削过程中的热应力、机械应力进行模拟，以残余应力与外加应力部分抵消为目标优化设计了梯度组成分布．按设计结果，采用粉末铺填－热压烧结工艺研制成功Ａｌ２Ｏ３／ＴｉＣ系梯度功能陶瓷刀具材料．

Based on the analyses of stress distribution in ceramic inserts and their failure mechanisms, a model for designing compositional distribution of ceramic tool materials with gradient is proposed for the first time in this paper. By means of simulation of residual thermal stress in fabricating process as well as thermal stress, mechanical stress of cutting tools with different compositional distributions in machining, the optimum design of compositional distribution was carried out with the aim of partial relaxation of external stress by residual thermal stress in fabricating process. Al2O3/TiC functionally gradient ceramic tool materials were synthesized via HP(hot_pressing) accordingly.