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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) was synthesized by the solid state reaction method. The tribological properties of the superconductor Bi2Sr2CaCu2Ox (Bi2212) were investigated by using a friction tester from liquid nitrogen temperature to room temperature. The results show that the friction coefficient between Bi2212 and stainless steel plate at room temperature is about 0.35. When the temperature is below the superconducting transition temperature (liquid nitrogen temperature), the friction coefficient is greatly reduced to 0.11, which is very stable. In order to improve the tribological properties of Bi2212 at room temperature, Ag / Bi2212 superconducting composites were prepared by adding Ag. XRD, SEM and EDS analysis showed that Ag did not enter into the lattice of Bi2212, which ensured the superconductivity of Bi2212. The addition of Ag increased the density of composites And toughness. The friction coefficient is 0.2 at 10% Ag and 10% Ag at normal load and gliding speed. The wear rate of Ag / Bi2212 is the lowest, 9.5 × 10-5mm3 (Nm) -1. The distribution of Ag in the matrix can effectively suppress the initiation and propagation of cracks and transfer to the surface under the action of friction, forming an Ag transfer film on the friction surface. The low shear strength plays a very good role in lubrication. At the same time, the heat generated by friction Conducted out in time, so that the composite material showed good anti-friction wear performance.