【摘要】 铝铌合金是具有较高强度及硬度的结构材料和涂层材料。采用 2kW连续波Nd YAG激光在AA60 61Al合金表面制备Al Nb金属间化合物激光合金化改性层。采用功率密度 62 .5J·mm- 2 ,交互作用时间 0 .0 65s ,保护气氩气流量为 2 0L·min- 1 的激光辐照处理工艺 ,可获得无孔洞及裂纹、致密的Al Nb金属间化合物改性层。采用光学显微镜、扫描电子显微镜、能谱仪、X射线衍射仪及显微硬度计 ,研究改性层的表面组织形貌 ,成分分布、组织结构及硬度分布。更多还原

【Abstract】 Al-Nb alloys present considerable strength and hardness, being promising materials for structural applications and for coatings. Al-Nb intermetallic compounds modification coating was fabricated by laser surface alloying using a continuous wave Nd-YAG laser on the 6061Al substrate. Surface alloyed coating was produced by a power density 62.5 J·mm -2, interaction time 0.065 s, shielding gas Ar flow 20 L·min -1, which has a good metallurgical bonding between the Al-Nb intermetallic compound layer and the substrate. A porous-free and crack-free surface layer was achieved by overlapping single tracks. The microstructure, surface appearance, composition distributing, hardness-depth profile were investigated by optical microscopy, scanning electron microscopy with an EDX electron probe microanalyser, X-ray diffractometry and microhardness tester, respectively.更多还原