Q690CFD热影响区粗晶区再热脆化研究

来源期刊：钢铁2010年第11期

论文作者：张熹 董现春 陈延清 章军

文章页码：86 - 89

关键词：Q690CFD； 粗晶区； 再热脆化； 焊后热处理

Key words：Q690CFD； coarse grain zone； reheat embitterment； postweld heat treatment

摘    要：讨论了焊后热处理制度对Q690CFD粗晶区冲击韧性的影响,发现焊后热处理温度在500℃附近存在脆韧转变点。金相、SEM、能谱试验结果表明碳化物在原奥氏体晶界析出是导致脆韧转变的原因,并利用Thermo-calc计算了碳化物的析出规律,与试验结果符合很好。最终根据试验结果优化了首钢Q690CFD焊后热处理工艺。

Abstract: The influence of postweld heat treatment system on the impact ductility of Q690CFD in coarse grain zone was discussed.The results indicate that the point of 500 ℃ is brittle ductile transition temperature.According to the experimental results of metallurgical structure,SEM and energy spectrum,the carbide precipitation at original austenite grain boundary results in the brittle ductile transition.The carbide precipitation regularity was computed by Thermo-calc.The calculated results have good relationship with the test results.Finally,the postweld heat treatment regime of Shougang′s Q690CFD was optimized.