摘要
采用化学镀方法在TC4钛合金表面制备了Ni-P镀层,通过不同的退火温度处理试件,研究了影响镀层结合力的影响因素。用SEM分析了不同温度处理后镀层的结构从而建立不同热处理温度、保温时间与扩散层厚度的动力学方程;采用X射线衍射研究了扩散界面的产物及不同退火温度对镀层的热应力的影响。结果表明:400℃,2h、400℃,4h热处理之后无扩散层出现;在500℃,2 h、500℃,4 h、600℃,2 h、600℃,4 h、700℃,2 h、700℃,4 h热处理后均出现扩散层,并根据扩散层的厚度与热处理温度和时间的关系推导出其扩散的动力学方程:y=2.72 exp(-6353/T)t;不同温度热处理后Ni-P镀层的热应力显著增加;热处理后镀层的结合力有所增加,400℃,2h、400℃,4h、500℃,4h热处理后镀层与基体的结合力最好。
Ni-P alloy coating on TC4 titanium alloy was prepared by an electroless plating method.The influence of annealing temperature on the adhesion of the Ni-P coating was investigated.Dynamic equation to describe the interface layers thickness,diffusion heat treatment temperature and holding time were established by SEM analysis.The product of the diffusion interface and the influence of different annealing temperatures on thermal stress of the coating were studied by X-ray diffraction.The results show that the Ni-P coatings has no diffusion layers when treated at 400 ℃ for 2 and 4 h,while the diffusion layers appear when treated above 400 ℃.The dynamic equation,y=2.72exp（-6353/T）t,can be obtained according to the relations between the thickness of the diffusion layer and the time as well as temperature of heat treatment.The thermal stress of the coating increases significantly after heat treatment;the adhesion of the coating with heat treatment is much higher than that without heat treatment.The best adhesion of the coating can be achieved when the heat treatments are 400 ℃×2 h,400 ℃×4 h and 500℃×4 h.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2017年第2期433-438,共6页
Rare Metal Materials and Engineering
关键词
TC4钛合金
热处理
扩散层
热应力
结合力
TC4 titanium alloy
heat treatment
diffusion layer
thermal stress
adhesion
