氢脆导致Q235B钢板断后伸长率不合格

Hydrogen embrittlement leads to failure of Q235B steel plate elongation at break

某南方钢厂,于梅雨季节期间持续出现Q235B钢板断后伸长率不合格的现象。为查清断后伸长率不合格原因,将同批次断后伸长率不合格与合格的试样进行力学性能试验、化学成分分析、断口形貌分析、金相检验等对比分析。结果表明:钢板中残留的氢元素,最终导致该Q235B钢板断后伸长率不合格,而钢中非金属夹杂物也是断后伸长率不合格的影响因素之一。为了验证上述分析,将该批次钢板进行去氢处理,经处理后的钢板氢脆现象消失,断后伸长率不合格现象得以消除。

A southern steel mills,in the rainy season during the continued emergence of Q235B steel plate elongation at break unqualified phenomenon.In order to find out the reason for unqualified elongation after break,the same batch of unqualified elongation after break and qualified specimens for mechanical properties test,chemical composition analysis,fracture morphology analysis,metallographic examination and other comparative analysis.The results show that:the residual hydrogen element in the steel plate ultimately leads to the unqualified elongation at break of the Q235B steel plate,and the non-metallic inclusions in the steel is also one of the influencing factors of the unqualified elongation at break.In order to verify the above analysis,the batch of steel plate was dehydrogenated,and the hydrogen embrittlement phenomenon disappeared after treatment,and the unqualified elongation at break phenomenon was eliminated.