玻璃喷丸处理提高304不锈钢焊接接头抗应力腐蚀性能的研究

基于对304不锈钢焊接试板表面喷丸处理前后的表层残余应力X射线衍射测量，研究了在42％沸腾MgCl2溶液中，表面玻璃喷丸和铸钢喷丸对304不锈钢焊接试板应力腐蚀开裂敏感性的影响，比较了采用不同铸钢喷丸和玻璃喷丸处理工艺的304不锈钢焊接试板抗应力腐蚀开裂的能力．试验结果表明：未喷丸处理的焊接试板6h就发生开裂，50％、100％覆盖率的铸钢喷丸焊接试板分别在试验310h和3500h开裂，而200％覆盖率的铸钢喷丸焊接试板，50％、100％、200％覆盖率的玻璃喷丸焊接试板经历3500h也未见开裂．因此，喷丸处理工艺能够很好地提高焊接构件抗应力腐蚀开裂能力；且在同样喷丸强度下，焊接接头经玻璃喷丸工艺处理后的抗应力腐蚀能力明显优于铸钢喷丸处理工艺．

PREVENTION OF STRESS CORROSION CRACKING IN WELD JOINT OF TYPE 304 STAINLESS STEEL BY GLASS-BEAD PEENING

Based on X-ray measurements of the residual stresses of shot peened and unpeened welded plates of 304 stainless steel,effects of glass bead peening and cast steel shot peening on stress corrosion susceptibility of weld joints of AISI type 304 stainless steel in boiling 42% MgCl_2 were studied.Comparison of the potential against SCC of specimens peened by glass beads and cast steel shots were carried on.The test results show:unpeened specimens crack within 6 hours.The steel-peened specimens with 50% coverage crack in boiling 42% MgCl_2 after immersion for 310 hours,while the steel-peened specimens with 100% coverage crack after immersion for 3500 hours.However,cast steel-peened specimens with 200% coverage and glass-peened specimens with 50%,100% and 200% coverage are tested for a total of 3500 hours without visible stress corrosion cracks in the peened surfaces.In a word,shot peening is an effective method for protecting weldments against SCC,and weldments peened by glass beads resist SCC better than those peened by cast steel shots.