摘要
利用6kW光纤激光器,采用预置粉末法在304不锈钢表面激光熔覆制备Fe17Mn5Si10Cr5Ni记忆合金涂层。利用扫描式电子显微镜、X射线衍射仪及往复摩擦试验仪等设备对涂层的微观组织、相组成进行研究,对涂层及基材的耐磨性能、接触疲劳特性进行对比分析,并利用小孔法对试样的残余应力进行测量。结果表明:记忆合金涂层自界面到顶端分别由平面晶、包状晶、柱状晶组成;涂层磨损机制为磨粒磨损,基材磨损机制为粘着磨损,涂层磨损量仅为基材磨损量的三分之一,耐磨性优于基材;涂层接触疲劳强度优于基材;熔覆试样残余应力较基材低。应力诱发γ→ε马氏体相变是涂层力学性能优异的根本原因。
With a 6 kW fiber laser, Fe17MnSSi10CrSNi shape memory alloy coating is obtained by powder presetting and laser cladding on the 304 stainless steel surface. Microstructure and phase composition of the coating is studied by the scanning electron microscope, X-ray diffractometer and reciprocating friction tester. Wear resistance and contact fatigue strength of the coating and substrate are analyzed, and residual stress is measured with the orifice method. Results show that the coating is composed of planar crystal, cellular crystal and columnar crystal from the bottom of molten pool to surface; wear mechanism of the coating is abrasive wear, while that of the substrate is adhesive wear, and wear loss of the coating is nearly a third of that of the substrate; and wear resistance and contact fatigue strength of the coating are better than those of the substrate. Besides, residual stress of the coating is smaller than that of the substrate. The key reason for good mechanical properties of the coating is the stress induced γ→ε phase transformation.
出处
《中国激光》
EI
CAS
CSCD
北大核心
2017年第2期257-262,共6页
Chinese Journal of Lasers
基金
贵州省高层次创新型人才计划[黔科合人才(2015)4009]
贵州省科技厅工业攻关项目[黔科合GZ字(2015)3022]
贵州省科技厅--贵州大学联合资金项目[黔科合LH(2015)7650]
关键词
激光技术
激光熔覆
记忆合金
涂层
应力
laser technique
laser cladding
shape memory alloy
coating
stress
