【摘要】 采用焊接热模拟试验和冲击试验,研究了X80管线钢焊接热循环对粗晶区组织性能的影响。结果表明,当焊接热输入为20 kJ/cm时,其热影响区粗晶区可获得最佳的韧性水平,其原因是产生了多位向分布的针状铁素体,它可作为X80管线钢埋弧焊的推荐焊接规范。在较高的焊接热输入下,X80管线钢的韧性降低,此时已开始出现对韧性构成损害的铁素体和珠光体。更多还原

【Abstract】 The influence of welding thermal cycle on structure and properties in grain-coarsening region of X80 pipeline steel was investigated by weld thermal simulation technique and the charpy test.The results show that the best toughness of the grain-coarsening region of X80 pipeline steel can be gotten when the welding heat input is 20kJ/cm.The reason is to produce acicular ferrite with multi-exposure distribution.It can be used as welding criterion of X80 pipeline steel submerged-arc welding.Under the higher heat input,the toughness of the X80 pipeline steel declines.At that time,ferrite and pearlite which are harm to the toughness appeare.更多还原