激光熔敷Ti5Si3/NiTi金属间化合物复合材料涂层组织与高温抗氧化性能研究  

Microstructure and Oxidation Resistance of a Laser Clad Ti5Si3/NiTi Intel-metallic Composite Coating

作　　者：刘元富[1] 赵海云[1] 张凌云[1] 王华明[1] 

机构地区：[1]北京航空航天大学材料学院,北京100083

出　　处：《应用激光》2002年第3期269-271,274,共4页Applied Laser

基　　金：国家自然科学基金(50101001);航空基础科学基金(00H51013);北京市自然科学基金(2022012)资助项目

摘　　要：以Ti—Si—Ni混合合金粉末为原料,利用激光熔敷技术,在高温、高强钛合金BT9表面制得了以金属间化合物Ti5Si3为强化相、以金属间化合物NiTi为基体的金属间化合物快速凝固高温抗氧化复合材料涂层。在1000℃恒温氧化50小时的试验条件下测试了涂层的抗氧化性及氧化动力学曲线,分析了复合材料涂层及氧化膜的显微组织结构及相组成。An oxidation resistant Ti5Si3/NiTi intermetallic matrix composite coating was fabricated on substrate of a titanium alloy BT9 by laser cladding using the Ni - Ti-Si alloy powders. The oxidation resistance of the laser clad intermetallic composide coating was investigated under the testing condition of 1000℃ and 50 hours. The results indicate that the laser clad intermetallic composite coating has a rapidly solidified homogeneous microstruc-ture consisting of Ti5Si3 primary particles uniformly distributed in the Ti5Si3/NiTi eutectic matrix and it is metal-lurgically bonded to the titanium substrate. The isothermal elevated -temperature oxidation resistance of the laser clad intermetallic composite coating is enhanced significantly. Oxidation resistance of the laser clad intermetallic composite coating was up to 1. 79 times higher than that of the original titanium alloy BT9. The oxidation kinetics of the laser clad γ/NiTi intermetallic composite coating is conforming to the parabolic-rate law equation at the testing condition. The excellent oxidation resistance of the coating is mainly attributed to that the relatively continuous oxide scales which mainly consist of TiO2, A12O3 and SiO2 prevented the inner part of the laser clad intermetallic composite coating from being further oxidized.

关 键 词：复合材料 涂层组织 高温抗氧化性能 激光熔敷 金属间化合物 金属硅化物 硅钛合金 

分 类 号：TB331[一般工业技术—材料科学与工程] TF19[冶金工程—冶金物理化学]