工艺参数对TiAl合金激光表面合金化改性层组织与耐磨性的影响  

Effects of processing parameters on microstructure and wear resistance of laser surface alloyed layer on TiAl alloy

作　　者：何秀丽[1] 王华明[1] 

机构地区：[1]北京航空航天大学材料科学与工程系,北京100083

出　　处：《中国有色金属学报》2000年第6期790-795,共6页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目! (5 96 710 5 0 ) ;航空基础科学基金资助项目! (95G5 10 0 5 );教育部优秀年轻教师基金资助项目

摘　　要：利用元素氮和元素碳对γ TiAl合金 (简称TiAl合金 )进行激光表面合金化处理 ,分别制得了以TiN及TiC硬质耐磨相为增强相的快速凝固原位耐磨复合材料表面改性层 ,改性层与基体间为完全的冶金结合 ,其显微组织从熔池底部到自由表面具有梯度渐变特征 ,越接近自由表面 ,增强相越密集。较系统地研究了激光表面合金化工艺参数对改性层显微组织以及在磨料磨损及滑动磨损条件下耐磨性能的影响。激光束扫描速度越低 ,表面改性层增强相体积分数越高 ,材料显微硬度提高越多 。Laser surface alloying with nitrogen and carbon were employed to produce modified layers on TiAl alloy. The rapidly solidified in situ composites layers reinforced by titanium nitride and titanium carbide were gained respectively, and the interfaces between the layers and substrate were metallurgic bonds. From bottom of molten bath to free surface, there was gradient change characteristic in microstructures. The nearer the free surface, the higher the volume fraction of reinforced phase. The effects of laser processing parameters on microstructures and wear resistance of surface alloyed layer were studied. With decreasing laser beam scanning rate, the volume fraction of reinforced phase increases, the microhardness of the samples increases and the wear resistance is improved. [

关 键 词：Γ-TIAL合金 激光表面合金化 耐磨性 工艺参数 

分 类 号：TG174.445[金属学及工艺—金属表面处理] TG146.23[金属学及工艺—金属学]