莫来石基复合陶瓷高温摩擦表面粘附机理的研究

STUDY ON ADHESIVE MECHANISM OF MULLITE BASED COMPOSITES AT ELEVATED TEMPERATURES

研究莫来石基复合陶瓷（ＺＴＭ、ＺＴＭ／Ａｌ）与氧化钇稳定氧化锆（ＴＺＰ）陶瓷构成的摩擦副，在干摩滑动条件下，ＺＴＭ、ＺＴＭ／Ａｌ陶瓷的磨损率随环境温度的升高而逐渐降低，其摩擦表面可生成粘附保护层并出现负磨损现象。ＺＴＭ、ＺＴＭ／Ａｌ陶瓷高温摩擦表面产生粘附保护层的主要机理是对偶件ＴＺＰ陶瓷中的Ｚｒ原子或磨屑向其摩擦表面扩散和吸附的结果。详细分析这种Ｚｒ原子表面扩散转移的主要影响因素，以及磨屑在摩擦表面物理吸附和化学吸附的机理，得出了“ＺＴＭ、ＺＴＭ／Ａｌ摩擦表面粘附层的形成，其实质是由‘被动受磨’向‘主动抗磨’的机制转变”的结论，并展望了该抗磨机理的工程应用前景。

The friction and wear properties of mullite based composites,such as ZTM and ZTM/Al,are dealt with when they wore against TZP cera mics under dry sliding.It is found that the wear rates of ZTM and ZTM/Al ceramic s decrease with the increase of temperatures and adhesive layers emerge on their surfaces. The main mechanisms of the formation of adhesive layers are surface d iffusion of Zr atoms from TZP to ZTM and ZTM/Al and/or the adsorption of debris on the surface of ZTM and ZTM/Al surfaces during the friction processes. The mai n factors affecting the Zr atom diffusion are analyzed. The physical and chemica l adsorption mechanisms of debris on ZTM and ZTM/Al surfaces are also studied. T herefore, a very important conclusion is that the formation of surfa ce adhesive protective layers on the surfaces of ZTM and ZTM/Al ceramics is the wear mechanism transition from `passive wear' to active anti wear'. The applie d fields of the anti wear mechanism are proposed as well.