摘要
设计了适用于强化疲劳试样的旋转辅助超声喷丸实验平台,采用技术手段对强化试样微观组织进行表征,结果表明:超声喷丸强化技术可以选取密度更大,硬度更高的喷丸小球来提高强化效率;超声喷丸处理对疲劳试样棒工作段硬度强化是非均匀的,强化区域沿层深方向硬度呈现梯度分布;强化区域表层呈现梯度纳米结构,晶粒细化机制为引入大塑性变形导致的连续动态再结晶;超声喷丸强化时间过长会导致过度喷丸,材料表面会萌生微裂纹。
A rotary-assisted ultrasonic shot peening experimental platform was designed for peening fatigue specimens and the features of the microstructure of reinforced specimens were investigated by technical means.The results show that:the ultrasonic shot peening technique can select the shot peening pellets with higher density and hardness to improve the peening efficiency.The hardness peening effect is not uniform for the working section of the fatigue specimen,and the hardness of the peening area shows a gradient distribution.The surface layer of the peening area shows a gradient nanostructures.The grain refinement mechanism is the introduction of dynamic recrystallisation caused by large plastic deformation.Excessive ultrasonic shot peening time will lead to excessive shot peening,and micro-cracks will develop on the material surface.
作者
尹飞
蔡旭阳
YIN Fei;CAI Xu-yang(School of Automotive Engineering,Wuhan University of Technology,Wuhan 430o70,China)
出处
《武汉理工大学学报》
CAS
2023年第6期1-11,共11页
Journal of Wuhan University of Technology
基金
国家重点研发计划(2020YFA0714900)
111学科创新引智计划(B17034)。
