16Mn(HIC)钢硫化物应力腐蚀开裂实验研究

Experimental investigation on sulfide stress corrosion cracking of 16Mn hydrogen-induced cracking resistance steel

摘要: 采用恒应变和慢应变速率拉伸实验的方法,研究了16Mn(HIC)和16Mn钢母材、焊缝在H₂S环境中应力腐蚀开裂.结果表明两种材料在酸性H₂S介质中均发生穿晶型硫化物应力腐蚀开裂(SSCC);与16Mn钢相比,16Mn(HIC)钢有更好的抗SSCC性能,钢中的C,Mn,P和S的含量降低有利于提高钢的抗SSCC性能.焊缝及热影响区在焊接过程中,产生的粗大魏氏组织、偏析、缩孔和夹杂等缺陷,降低了焊缝的抗SSCC能力.但是,通过焊后热处理可以适当提高焊缝的抗SSCC能力.

Abstract: Constant strain bend and slow strain rate tests (SSRT) were used to investigate the resistance to sulfide stress corrosion cracking (SSCC) of 16Mn and 16Mn hydrogen-induced cracking (HIC) resistance steels and their welded seams in acid solutions with saturated hydrogen sulfide gas, The results show that all of sampies are sensitive to SSCC in the acidic solutions with H₂S. The mechanism of cracking is HIC and most cracks are transgranular type. The resistance to SSCC of 16Mn(HIC) steel with low content elements C, Mn, P and S is better than that of 16Mn steel. Otherwise, the welded seams have less resistance to SSCC than their matrix because of big crystals, inclusions, vacancies and defects produced in the process of welding, but the work of post welding heat treatment (PWHT) can increase the resistance of their welded seams.