激光冲击处理对焊接接头力学性能的影响(Ⅰ)  

The Effects of Laser Shock Processing on Mechanical Properties of Welded Jionts(I)

作　　者：邹世坤[1] 王健[1] 王华明[2] 

机构地区：[1]北京航空工艺研究所,北京100024 [2]北京航空航天大学,北京100083

出　　处：《焊接学报》2001年第3期79-81,共3页Transactions of The China Welding Institution

摘　　要：当短脉冲、高峰值功率密度 (>10 13 W /m2 )的激光辐射金属靶材时 ,就产生高温、高压等离子体 ,该等离子体受到约束层的约束时产生高强度应力波冲击金属表面并向内部传播 ,在材料表面产生应变硬化 ,称这种表面强化技术为激光冲击处理或激光喷丸。激光冲击处理可以提高材料表层硬度、强度 ,并获得比传统的喷丸技术更深的硬化层或残余压应力层 ,从而更有利于材料疲劳性能的提高 ,为研究激光冲击处理在焊后强化方面的应用 ,本文对 1.6 6mm厚的镍基高温合金GH30、1.2mm厚的奥氏体不锈钢1Cr18Ni9Ti板材焊缝进行了激光冲击处理 ,对比了激光冲击处理试件和未经激光冲击处理试件焊逢的表层显微硬度、残余应力、抗拉强度和疲劳寿命 ,发现激光冲击处理能提高GH30氩弧焊焊接接头抗拉强度 12 % ,提高 1Cr18Ni9Ti等离子焊接接头疲劳寿命30 0 %以上。When a short pulse,high peak power (>10 13 W/m 2 ) laser irradiated to a metel surface,an impulsive wave,which is generated by a high pressure and high temperature plasma confined by the transparent medium,propagates into the material interior,thereby inducing strain hardening.We call this surface strengthening technology as 'laser shock processing' or 'laser shock peening'.The laser shock processing(LSP) can improve the surface hardness,tensile strength and gain a compressive stress layer or hardened layer with thickness much lager than that in the case of conventional peening,which is more benefit for the improvement of fatigue properties.In order to study the application of laser shock processing as a post weld treatment technology,the welded beads of a Ni base super alloy GH30 sheet with thickness of 1.66mm and a austenitic stainless 1Cr18Ni9Ti with thickness 1.2mm were shocked by pulse laser,then the surface residue stress,microhardness,ultimate tensile strength and the fatigue life were compared with those without LSP in this paper.The results show that the ultimate tensile strength of GH30 argon arc welded joints was increased by 12% and the fatigue life of 1Cr18Ni9Ti plasma welded joints was increased more than 300% after shocking.

关 键 词：激光冲击处理 激光喷丸 焊接接头 抗拉强度 疲劳寿命 力学性能 

分 类 号：TG407[金属学及工艺—焊接] TG441.8