Comparative Study on Microstructures of Zincalume Steel(G550)Welded Joint Between Metal Inert Gas and Laser Beam Welding  

作　　者：Walisijiang Tayier Shamini Janasekaran Syed Menhazul Bari 

机构地区：[1]Center for Advanced Materials and Intelligent Manufacturing,Faculty of Engineering,Built Environment and Information Technology,SEGi University Sdn Bhd,Petaling Jaya 47810,Malaysia

出　　处：《Journal of Harbin Institute of Technology(New Series)》2021年第5期89-96,共8页哈尔滨工业大学学报（英文版）

基　　金：This research was supported in part by the SEGi University Sdn Bhd(Grant Number:SEGiIRF/2018-10/FoEBE-17/80)and in kind contribution of University of Malaya.

摘　　要：Zincalume steel(G550)is commonly used in various construction fields because of its high corrosion resistance and good mechanical properties.In recent years,a number of steel companies have massively produced zincalume steel(G550)with large volumes of waste.For the reduction of massive industrial wastes,the zincalume steel(G550)was welded in the lap joint configuration using different welding parameters in the metal inert gas(MIG)welding and laser beam welding(LBW)process in this study.The MIG welding and LBW are more welcomed welding methods due to their high efficiency and low cost.However,they are different as the LBW offers welding speed three to five times faster than MIG welding,while LBW’s heat transfer to workpieces is much less than MIG welding,which can avoid some distortions.The microstructure of zincalume steel(G550)was investigated using scanning electron microscopy(SEM)and the microstructure characterizations of welded specimens were analyzed.The experiment found the columnar dendrites extended under the heat flow direction during the MIG welding and LBW process.Thus,the columnar grains were formed in between the equiaxed zone and fusion zone(FZ)at high heat input and slow cooling rate.Moreover,the grain size of FZ was comparatively smaller than heat affected zone(HAZ)and base metal(BM).

关 键 词：zincalume steel(G550) metal inert gas(MIG) laser beam welding(LBW) MICROSTRUCTURES 

分 类 号：TG44[金属学及工艺—焊接]