光学学报, 2017, 37 (9): 0914001, 网络出版: 2018-09-07
TC6钛合金激光喷丸组织演变与表面强化机理 下载: 1041次
Microstructure Evolution and Surface Strengthening Mechanism of TC6 Titanium Alloy by Laser Peening
激光技术 激光喷丸 TC6钛合金 组织演变 表面强度 laser technique laser peening TC6 titanium alloy microstructure evolution surface strength
摘要
研究了激光喷丸(LP)TC6钛合金的组织演变对表面强度的影响机理。结果表明,LP后材料表面的显微硬度和残余应力均随功率密度的增加而增大,LP引起的硬度影响层和残余应力影响层的深度也随功率密度的增加而增大,且影响层深度为500~600 μm。LP对TC6钛合金强度的影响机理包括细晶强化和位错强化,晶粒细化使大角度和小角度晶界增多,而晶界能阻止材料发生屈服;LP产生的高密度位错可使材料的屈服强度提高,阻碍位错的运动,抑制裂纹的萌生,从而使材料的力学性能提高。
Abstract
The mechanism and the effect of microstructure evolution on the surface microhardness of TC6 titanium alloys after laser peening (LP) are studied. The results show that both of the surface microhardness and the residual stress of materials after LP increase with the increase of the power density, and the depths of the microhardness effect layer and the residual stress effect layer caused by LP also increase with the increase of the power density, and the depths are 500-600 μm. The effect mechanism of LP on the microhardness of TC6 titanium alloys consists of the fine grain strengthening and the dislocation strengthening. The number of large and small angle grain boundaries increases because of the grain refinement and the grain boundary can prevent the materials to yield. High density dislocations produced by LP can improve the yield strength of materials, hinder the movement of dislocations and restrain the crack initiation, which can improve the mechanical property of materials.
杨祥伟, 周建忠, 盛杰, 孟宪凯, 黄舒, 杨颖秋. TC6钛合金激光喷丸组织演变与表面强化机理[J]. 光学学报, 2017, 37(9): 0914001. Xiangwei Yang, Jianzhong Zhou, Jie Sheng, Xiankai Meng, Shu Huang, Yingqiu Yang. Microstructure Evolution and Surface Strengthening Mechanism of TC6 Titanium Alloy by Laser Peening[J]. Acta Optica Sinica, 2017, 37(9): 0914001.