摘要
评价了对300M合佥钢2种表面强化技术的疲劳性能。结果表明，HVOF WC／Co，电镀铬涂层和300M基体的疲劳极限强度分别为753．3MPa，600．0MPa和726．7MPa。HVOF WC／Co使基体疲劳寿命提高25％～150％；电镀铬大幅度降低基体的疲劳性能，疲劳寿命降低幅度达70％～95％。疲劳断裂分析表明，三者的主裂纹源均是基体内夹杂物质。电镀铬中的裂纹穿过界面并向基体中扩展，加快了裂纹源的形成和裂纹的扩展，而HVOF WC／Co涂层中的裂纹在经过界面时偏转向沿界面方向，这对裂纹源的形成和主裂纹的扩展没有影响。
The fatigue properties of surface-strengthened 300M low alloy steel are evaluated. The results show that the fatigue limit of substrate strengthened by HVOF WC/Co is 753. 3, substrate strengthened by Chromium electroplating 600.0 and bare substrate 726.7MPa. The fatigue life of HVOF WC/Co increases 25 -150% comparing with that of substrate. The Chromium electroplating greatly reduces the fatigue life by 70- 95%, Fracture analysis reveals that the main fracture is initiated at the subsurface under three conditions. The analysis also observes that the crack in the Chromium electroplating coating spreads through the interface and finally into the substrate, which hastens the formation of crack initiator and the extension of crack, however, the crack in the HVOF WC/Co coating deflects at the interface and crack spreads through the interface and finally leads to the formation of free -- standing coating, Therefore, the crack forming in the coatings has no negative influence on the main crack initiator and crack extension in the substrate.
出处
《新技术新工艺》
2006年第2期89-91,共3页
New Technology & New Process
关键词
表面强化
疲劳
断裂
surface-strengthening technique, fatigue, fracture
