TC4钛合金表面激光合金化制备Ti-Si涂层

Ti-Si coating by laser alloying on TC4 titanium alloy

摘要:

以Ti、Si单质元素混合粉末为原料,采用激光合金化技术在钛合金表面成功制备出了Ti-Si合金涂层。分析了涂层的组织形貌、成分和物相组成,测试了涂层的显微硬度及与YG6在干摩擦磨损条件下的摩擦磨损性能。结果表明：在合适的激光合金化参数下制备的Ti-Si涂层整体均匀致密,无裂纹且与TC4基体呈良好的冶金结合；涂层组织主要由针状的α-Ti基体和网状分布的Ti₅Si₃/β-Ti共晶体(室温下为Ti₅Si₃/α-Ti)组成；自下而上涂层组织细化,硬度在HV 660 ~ 730之间,与TC4钛合金相比,平均摩擦系数降低(0.39VS0.45),耐磨性提高2.4倍。

Abstract:

Using Ti and Si elemental elements mixed powder as raw material, Ti-Si alloy coating was successfully fabricated on the surface of titanium alloy by laser alloying. Microstructure morphology, composition and phase of the coating were investigated. Microhardness and tribological properties under dry friction and wear conditions were tested. The results show that: the Ti-Si coating under the appropriate parameters of laser alloying prepared is uniform and dense, crack-free, and combined with a generally good metallurgical TC4 base; coating microstructure is consisted of needle-like α-Ti matrix and network distribution of Ti5Si3/β-Ti eutectic (room temperature is Ti5Si3/α-Ti) composition; the hardness of the coating is between HV 660 ~730;compared with TC4 titanium alloy, the average friction coefficient decreases (0.39VS0.45) and wear resistance increased 2.4 times.