焊接热循环参数对大线能量焊接用钢EH40热影响区组织和性能的影响

利用热模拟技术及光学显微镜、透射电镜研究了焊接热循环参数对大线能量焊接用船板钢热影响区组织和性能的影响.发现模拟焊接热影响区组织主要由粒状贝氏体、铁素体和珠光体组成,且随着峰值温度和冷却时间的变化,热影响区的组织发生较大的变化;热影响区的冲击韧性总体水平较高,均在200 J以上,冲击韧性并不随着峰值温度和冷却时间的增加而单调变化;热影响区M-A岛的数量、尺寸、分布和形态影响热影响区的韧性. 

Effect of welding thermal cycle parameters in the heat affected zone of steel EH40 for on the microstructure and properties high heat input welding

The effects of welding thermal cycle parameters on the microstructure and properties in the heat affected zone (HAZ) of hull structure steel for high heat input welding were studied by thermal simulation technique, optical microscopy and transmission electron microscopy (TEM). It is found that the microstructure of the simulated HAZ is mainly composed of granular bainite, ferrite and pearlite, but it varies markedly with the change of peak temperature and cooling time. The overall level of impact toughness of the simulated HAZ is higher than 200 J, and the impact toughness does not monotonously change with the peak temperature and the cooling time increasing. The amount, size, distribution and shape of M-A constituents in the simulated HAZ are the main influencing factors on the impact toughness.