X80管线钢焊接热影响区的二次脆化研究

Quadratic Short Study of Welding Heated Affect Zone on Grade X80 Pipeline Steel

采用热模拟技术研究了二次热循环对X80级管线钢焊接粗晶区性能的影响。试验结果表明,一次峰值温度1300℃作用后,再经过800℃二次热循环时韧性显著下降,发生严重脆化;经过1200℃二次热循环作用时韧性最好,断口形貌为韧窝状。一次热循环峰值温度800℃作用后,再经过1300℃的二次峰值温度作用,其冲击韧性远远低于母材,发生严重脆化,断口形貌为解理状。

To study quadratic heat circulation to the effect of welding wide crystal area performance of X80 pipeline steel by adopting thermal simulation technology.The experimental results show that it will occur seriously short after once peak value temperature 1300℃ and the toughness prominently decrease then through 800℃ quadratic heat circulation;the toughness is the best through 1200℃ quadratic heat circulation and the fracture appearance shows tight nest type.The impacting toughness is far off lower than that of parent metal and occurs seriously short and the fracture appearance shows unbind texture type after once peak value temperature 800℃ and then through 1300℃ quadratic peak value temperature.