论文部分内容阅读
为研究焊接热输入量对SMA490BW耐候钢粗晶区(CGHAZ)低温韧性的影响,利用Gleeble-1500热模拟试验机对SMA490BW耐候钢进行CGHAZ的热模拟试验,并对不同热输入量下的热模拟CGHAZ进行-40℃低温冲击试验。结果表明:随着焊接热输入量的增加,焊接热模拟粗晶区的低温冲击韧性降低,但当热输入量不超过30 k J/cm时,其冲击功均符合标准规定的不小于27 J的要求。焊接热模拟粗晶区粒状贝氏体增多、羽毛状贝氏体形成以及晶粒粗大是导致低温冲击韧性下降的主要原因。
In order to study the influence of welding heat input on the low temperature toughness of CGHAZ in SMA490BW weathering steel, the thermal simulations of CGHAZ on SMA490BW weathering steel were carried out by Gleeble-1500 thermal simulation testing machine. The thermal simulation under different heat input CGHAZ -40 ℃ low temperature impact test. The results show that with the increase of welding heat input, the low temperature impact toughness of the welding heat-treated coarse grain zone decreases. However, when the heat input does not exceed 30 kJ / cm, the impact energy of the welding heat treatment line meets the standard requirement of not less than 27 J Request. Welding thermal simulation of coarse grained granular bainite, feathery bainite formation and coarse grains are the main reasons leading to the decline of impact toughness at low temperature.