熱處理工藝對FV520(B)鋼焊接接頭耐蝕性能的影響

熱處理工藝對FV520(B)鋼焊接接頭耐蝕性能的影響Effects of Heat Treatment Processes on Corrosion Resistance of Welded Joint of FV520(B) Steels

首先對FV520（B）鋼進行焊接，之后對母材及焊接接頭進行不同工藝的熱處理，然后將它們浸泡在質量分數為10%的H2SO4溶液中進行腐蝕試驗，研究了熱處理工藝對焊接接頭耐蝕性能的影響。結果表明：不同熱處理后的FV520（B）鋼焊接接頭的表面腐蝕形貌都較為均勻平整，但在熔合區附近存在較深的斷層，且有深陷的溝壑狀腐蝕坑；在相同的熱處理條件下，母材的腐蝕速率均高于焊接接頭的；在固溶處理與時效處理工序間增加調整處理工序可以提高焊接接頭和母材的耐蝕性能；在850℃進行調整處理后焊接接頭的表面腐蝕形貌要比在750℃進行調整處理的更均勻平整。

Welding experiment was carried out on FV520(B) steels, and then different heat treatments were carried out on base metal and welded joint. Then corrosion experiments of base metal and welded joint were executed in 10wt% H2SO4 solution to study the effects of heat treatment processes on corrosion resistance of welded joint. The results show that, after different heat treatments, the surface corrosion morphology of FV520(B) steel welded joint was relatively uniform, but deep fault and ravined corrosion pits were found near the fusion zone. Under the same heat treatment conditions, the corrosion rate of base metal was higher than that of the welded joint. The corrosion resistance of welded joint and base metal could be improved through adding intermediate treatment between solid solution and aging processes. After intermediate treatment at 850℃, the welded joint owned more uniform surface morphology than the welded joint after intermediate treatment at 750℃.