Ag／Bi2Sr2CaCu2Ox复合材料摩擦学特性  

Tribological properties of Ag/Bi_2Sr_2CaCu_2O_x composites

作　　者：董丽荣[1,2] 李长生[1,1] 王旻璐[1] 彭义[1] 

机构地区：[1]江苏大学材料摩擦学省重点实验室,镇江212013 [2]吉林师范大学物理学院,四平136000

出　　处：《复合材料学报》2009年第2期125-130,共6页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金资助项目(50372026)

摘　　要：釆用固态反应法合成超导体Bi2Sr2CaCu2Ox(Bi2212),使用摩擦实验机从液氮温度至室温对其摩擦学特性进行研究。研究表明:室温Bi2212与不锈钢盘对摩时摩擦系数约为0.35,当温度降至超导转变温度以下(液氮温度),摩擦系数大幅度降低至0.11,非常稳定。为改善Bi2212常温摩擦性能,添加Ag制备出Ag/Bi2212超导复合材料,XRD、SEM和EDS分析表明,Ag未进入Bi2212晶格,保证了Bi2212的超导电性,Ag的添加提高了复合材料密度和韧性,在正常载荷和滑行速度下Ag质量分数为10%时摩擦系数为0.2,15%Ag/Bi2212磨损率最低,为9.5×10-5mm3(N.m)-1。分布基体中的Ag能有效抑制裂纹萌生和扩展并在摩擦作用下向表面转移,在摩擦表面形成一层Ag转移膜,其低剪切强度起到很好的润滑作用,同时将摩擦产生的热量及时传导出去,使复合材料表现出良好的减摩耐磨性能。The superconductor Bi2Sr2CaCu2Ox （Bi2212） samples were synthesized by the solid-state reaction method, and the tribological properties were investigated on the friction and wear tester from ambient temperature to liquid nitrogen temperature. The results indicate that the friction coefficient of the Bi2212 against stainless steel is about 0.35 at ambient temperature and abruptly decreases when the temperature is cooled below superconducting transition temperature of the Bi2212, as low as 0.11. Ag/Bi2212 composites were prepared by sintering Bi2212 with Ag at different mass fractions to improve the tribological properties of Bi2212 at ambient temperature. The structure and morphology were investigated by means of XRD, SEM, and the elemental compositions of the worn surfaces of Ag/Bi2212 composites were determined using energy dispersive X-ray analysis （EDS）. The results show that the Ag particles distribute in the Bi2212 matrix, improving the density, flexibility and toughness of Ag/Bi2212 composites, and a soft metallic Ag film forms on the surface of Ag/Bi2212 composite during friction process and lowers the friction coefficient. The friction coefficient of 10%Ag/Bi2212 against stainless steel shows a lower value （0.2）, and the wear rate of 15%Ag/Bi2212 is minimum （9.5 × 10^-5 mm^3 （N.m）^-1） at ambient temperature. Ag/ Bi2212 composites show improved tribological properties.

关 键 词：Bi2212 AG 复合材料 超导转变温度 摩擦学特性 

分 类 号：TB332[一般工业技术—材料科学与工程]