铋锶钙铜氧超导陶瓷的低温摩擦学特性  

LOW TEMPERATURE TRIBOLOGICAL PROPERTIES OF Bi_2Sr_2Ca_2Cu_3O_y SUPERCONDUCTING CERAMICS

作　　者：董丽荣[1,2] 李长生[1] 唐华[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,江苏镇江212013 [2]吉林师范大学物理学院,吉林四平136000

出　　处：《硅酸盐学报》2009年第8期1385-1390,共6页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金50372026资助项目

摘　　要：釆用低温摩擦实验机,研究了Bi2Sr2Ca2Cu3Oy(Bi2223)超导陶瓷从液氮温度至室温的摩擦学特性。结果表明:室温下Bi2223超导陶瓷与不锈钢盘对摩时摩擦系数约为0.40,温度降到液氮温度后Bi2223超导陶瓷处于超导态,摩擦系数突然降到0.17,且非常稳定。为改善Bi2223常温摩擦性能,添加Ag制备了Ag/Bi2223超导陶瓷,对其进行了X射线衍射、扫描电镜和高分辨透射电镜分析。结果表明:Ag未进入Bi2223晶格,沒有影响Bi2223的超导性,Ag的添加提高了材料的韧性。在正常载荷和滑行速度下Ag的质量分数(下同)为20%时,Ag/Bi2223超导陶瓷的摩擦系数为0.27,5%Ag/Bi2223超导陶瓷的磨损率最低,为1.78×10–5mm3/(N·m),Ag/Bi2223超导陶瓷在摩擦的过程中,Ag转移到摩擦表面,其低的剪切强度起到润滑作用。The tribological properties of the Bi2Sr2Ca2Cu3Oy （Bi2223） superconducting ceramic samples were investigated using a friction and wear tester from liquid nitrogen temperature to ambient temperature. The results indicate that the friction coefficient of the Bi2223 against stainless steel is about 0.40 at ambient temperature and abruptly decreases when the temperature is cooled to liquid nitrogen temperature; at this temperature, the friction coefficient of the ceramic is about 0.17 and it is stable. Ag/Bi2223 superconducting ceramics were prepared by sintering Bi2223 with Ag to improve the tribological properties of Bi2223 at ambient temperature. The structure and morphology of the Ag/Bi2223 ceramics were investigated by means of X-ray diffraction, scanning electronic microscopy and high resolution transmission electron microscopy. The results show that the Ag particles are distributed in the Bi2223 matrix, improving the toughness of Ag/Bi2223 superconducting ceramics and a soft metallic Ag film forms on the surface of Ag/Bi2223 superconducting ceramics during the friction process. Ag/Bi2223 superconducting ceramics have improved tribological properties. The friction coefficient of 20% （in mass, the same below） Ag/Bi2223 against stainless steel is about 0.27 and the wear rate of 5%Ag/Bi2223 is the minimum （1.78 × 10^-5 mm^3/（N.m））.

关 键 词：铋锶钙铜氧 银 超导陶瓷 摩擦系数 磨损率 

分 类 号：TB34[一般工业技术—材料科学与工程]