论文部分内容阅读
为了研究X80管线钢在低温环境下焊接的接头性能,本文对X80钢采用焊条电弧焊模拟不同温度条件进行焊接,并对获得的焊接接头进行拉伸试验、冲击试验、硬度测试及金相观察,利用SEM观察焊接接头断口形貌。结果表明:X80钢在低温环境下焊接接头的拉伸强度、冲击韧性等力学性能都较常温环境下低,而硬度值有所上升;随着焊接温度的降低,X80钢焊接接头的断裂方式由韧性断裂逐渐转变为脆性断裂。
In order to study the joint performance of X80 pipeline welded at low temperature, X80 steel was simulated by different temperature conditions using arc welding. The tensile test, the impact test, the hardness test and the metallographic observation of the obtained welded joint were carried out. The fracture morphology of welded joints was observed by SEM. The results show that the mechanical properties of X80 steel such as tensile strength and impact toughness are lower than those at room temperature under low temperature, while the hardness value of X80 steel increases. With the decrease of welding temperature, the fracture mode of X80 steel is The ductile fracture gradually transforms into brittle fracture.