摘要
利用溶胶-凝胶方法合成高温超导YBa2Cu3O7-δ(YBCO)纳米粉体,分别以纯Ag和AgNO3向YBCO中掺杂金属银,制备了具有超导性能的固体润滑复合材料,并对其组织和摩擦学性能进行了研究。结果表明YBCO室温下摩擦因数大,以2种方式加入适量Ag后,得到从室温至500℃摩擦因数在0.15左右的固体润滑材料。XRD、SEM、EDS金相分析表明,分布在YBCO晶粒间的Ag微粒有效抑制微裂纹的萌生和扩展,改善了陶瓷YBCO的脆性。常温和高温下,复合材料都表现出低而稳定的摩擦因数,其机制是Ag颗粒在复合材料基体上形成转移膜,Ag的加入量以质量分数10%为最佳,尤其是由AgNO3制备出的复合材料,Ag颗粒粒径更小,分布更加均匀,表现出更好的性能。
Two series of YBa2 Cu3 O7-δ （YBCO） with different dopant were prepared by the method of sol-gel through adjusting the content of Ag and AgNO3 ,which is added to YBCO as a second phase,and their structures, morphologies and tribological properties were studied. The results of XRD, SEM and EDS analysis show that the Ag particles are uniformly distributed in the YBCO matrix, and they can improve the flexibility, strength and fracture toughness of YBCO. The friction coefficient of the composite is low and stabile from room temperature to high temperature, and the friction coefficient can maintain in about 0. 15 during room temperature and 500 ℃. During friction process ,the soft metal Ag-film which formed on the composite surface is the main mechanism which leads low friction coefficient, and the content of Ag 10% （weight） is optimum. Due to the finer and disperser Ag particles in matrix, composite mixed AgNO3 solution shows better overall properties.
出处
《润滑与密封》
CAS
CSCD
北大核心
2007年第9期64-67,144,共5页
Lubrication Engineering
