摘要
采用超声波喷丸装置,对AA2024进行不同覆盖率(100%,200%,300%)和相同强度的超声波喷丸,研究了喷丸前后的表面粗糙度、显微硬度、残余应力场及半高宽等表面完整性特征参数以及覆盖率对疲劳寿命的影响。结果表明:覆盖率对表面完整性和疲劳寿命有重大影响,采用300%覆盖率喷丸,可以使AA2024保持较小的表面粗糙度值(R a=1.6μm),较高的显微硬度,较好的残余应力分布及稳定的表面层微观组织,这些因素使得AA2024的疲劳寿命提高了5倍以上;而100%和200%覆盖率对应的疲劳寿命则分别提高了2倍和4倍。
AA2024 was peened by ultrasonic shot peening machine,with the same peening intensity and the different coverages( 100%,200%,300%). The changes of surface integrity such as roughness,micro hardness,residual stress profile and full wave at half maximum caused by different ultrasonic shot pening coverage and their effects on high cycle fatigue life were studied. The results show that shot peening coverage has significant influence on surface integrity and fatigue life. Compared with the other shot peening coverage,AA2024 has the smoother surface( R a= 1. 6 μm),higher micro hardness,excellent residual stress profile and stable micro- structure when sample under 300% shot peening coverage. AA2024 fatigue life was improved by about 5 times by these factors influence. Moreover,the fatigue life was improved by 2 times and 4 times under 100% and 200% shot peening coverage respectively.
出处
《制造技术与机床》
北大核心
2013年第12期144-146,150,共4页
Manufacturing Technology & Machine Tool
基金
国家自然基金项目:高能高应变率金属板料超声喷丸成形的基础研究(51175257)
关键词
超声波喷丸
覆盖率
残余应力场
疲劳寿命
Ultrasonic Shot Peening
Coverage
Residual Stress Profile
Fatigue Life
