激光熔覆Ni_(59.35)Nb_(34.45)Sn_(6.2)非晶复合涂层组织与性能研究

Study on Microstructure and Performance of Ni_(59.35)Nb_(34.45)Sn_(6.2) Amorphous Composite Coating Prepared by Laser Cladding

为了达到研究预置激光熔覆可以在45钢上制备Ni基非晶合金涂层的目的,采用非晶形成能力三判据原则及非晶成分团簇线定律法则,选择了采用常规非晶合金制备方法中具有极大玻璃形成能力(GAT)的Ni59.35Nb34.45Sn6.2合金粉末,在保护气氛下,制备非晶涂层,并对不同输出功率下得到的涂层进行微观组织和结构表征及性能测试。结果表明:激光熔覆Ni59.35Nb34.45Sn6.2涂层中除含有非晶相外还含有Nb3Sn、Nb2Ni、Ni3Sn2及Ni和Sn的氧化物相。当激光功率为3300W时,熔覆层表层显微硬度值最大为1638.1HK;涂层由于非晶相的存在耐蚀性有明显提高,在该功率下致钝电流密度和维钝电流密度都达到最小,分别为1.3537mA/cm2和0.2652mA/cm2。

In order to reach the purpose of using pre-laser cladding method preparation of Ni-based amorphous alloy coatings on 45 steel substrate surface by the method was carried out. The principles of the three clusters and the amorphous line of the law of composition rules were used. The Ni59.35Nb34.45Sn6.2 alloying powder which has a great glass-forming ability （GAT） in conventional preparation methods of amorphous alloys was chosen. In the protection of atmosphere,the amorphous surface coating was prepared. The microstructure,micro-hardness and performance of the different output power of the laser cladding were analyzed. The results show that,the laser cladding Ni59.35Nb34.45Sn6.2 amorphous composite coating include amorphous and Nb3Sn,Nb2Ni,Ni3Sn2,Ni and Sn oxide phase. When the power is 3300 W,the micro-hardness of the coating surface reaches as high as 1638.1 HK; Coating has improved corrosion resistance due to the existence of amorphous. In the power,induced blunt-dimensional current density and current density reach a minimum,they are 1.3537 and 0.2652 mA/cm2.