Application of vibration to enhance efficiency of friction stir processing  

应用振动提高搅拌摩擦加工效率（英文）

作　　者：M. ABBASI M. GIVI B. BAGHERI 

机构地区：[1]Faculty of Engineering, University of Kashan, Kashan, Iran [2]Department of Mining and Metallurgy, Amirkabir University of Technology, Tehran, Iran

出　　处：《Transactions of Nonferrous Metals Society of China》2019年第7期1393-1400,共8页中国有色金属学报（英文版）

摘　　要：Friction stir processing (FSP) is a solid-state modification method to process the surface of metals. In this process, due to rotation and traverse motions of a non-consumable tool, metal surface microstructure is refined and its mechanical characteristics are improved. Different methods have been applied to improving the efficiency of FSP. In this research, a new method entitled friction stir vibration processing (FSVP) was presented to enhance the efficiency of FSP. In this method, metal workpiece was vibrated normal to processing line during FSP. Microstructure and mechanical properties including hardness, ultimate tensile strength (UTS) and elongation of Al5052 alloy specimens processed using FSP and FSVP methods were analyzed and compared. The results showed that grain size decreased by about 33% as vibration was applied. It was also observed that ultimate tensile strength as well as hardness increased by about 7% as FSVP was applied. This was related to the enhanced straining of metal surface material as vibration was applied. The increase in straining results in the increase of dislocation density. It leads to more development of high angle grain boundaries due to dynamic recrystallization. The results also showed that UTS and elongation of FSV processed specimens increased as vibration frequency increased.搅拌摩擦加工(FSP)是一种处理金属表面的固态改性方法。在此过程中,由于非自耗刀具的旋转和来回移动,使金属表面组织细化、力学性能提升。提高FSP 效率的方法较多,本研究中采用的是一种叫振动搅拌摩擦加工(FSVP)的新方法。在此方法中,金属工件在FSP 过程中与加工线垂直振动。分析比较FSP 法和FSVP 法加工的Al5052 合金试样的显微组织和力学性能,包括硬度、极限抗拉强度(UTS)和伸长率。结果表明,采用FSVP 后,振动可使材料的晶粒尺寸减小约33%,极限抗拉强度和硬度提高约7%。这与振动作用下金属表面材料的应变增强有关。应变增加导致位错密度增加,动态再结晶使大角度晶界进一步发育。结果还表明,FSV 加工试样的极限抗拉强度和伸长率均随振动频率的增加而增加。

关 键 词：friction stir vibration processing friction stir processing microstructure mechanical properties 

分 类 号：TG178[金属学及工艺—金属表面处理]