摘要
Friction stir welding(FSW)was used to prepare Q235 low-carbon steel joint,and the microstructure of different zones of the joint was characterized.The electrochemical corrosion behavior of different macroscopic zones of the joint was evaluated in 3.5 wt.%NaCl solution.The results showed that the retreated-side heat-affected zone(HAZRS)and the advanced-side heat-affected zone(HAZAS)did not undergo phase transformation during FSW,and their microstructures were similar to those of the base material(BM),which was mainly composed of blocky ferrite and pearlite.The retreated-side thermo-mechanical affected zone(TMAZRS),the stirring zone(SZ),and the advanced-side thermo-mechanical affected zone(TMAZAS)underwent phase transformation,and the microstructure was mainly composed of proeutectoid ferrite and pearlite.The order of the corrosion resistance of different micro-zones from high to low was:HAZRS>BM>HAZAS>TMAZRS>SZ>TMAZAS.The corrosion mechanism for BM,HAZRS,and HAZAS was mainly the dissolution of ferrite.By contrast,the corrosion mechanism for TMAZRS,SZ,and TMAZAS was mainly galvanic corrosion between proeutectoid ferrite and pearlite.
基金
from the State Key Program of National Natural Science Foundation of China(Nos.U1760201 and 52034005)
the National Natural Science Foundation of China(Nos.51974220 and 52104383)
the Key Research and Development Program of Shaanxi Province(Nos.2020ZDLGY13-06 and 2017ZDXM-GY-037)
the Innovation Capacity Support Project of Shaanxi Province-Nova Program(No.2020KJXX-077)
the Science Fund for Distinguished Young Scholars in Universities of Shaanxi Province.
