An investigation into the weldability of SA-738Gr.B steel

作者:Ding L Z; Lei Y; Zhang J; Meng Q S*
来源:Materials Research Innovations, 2015, 19(sup5): 1197-1201.
DOI:10.1179/1432891714z.0000000001277

摘要

In this experiment, the microstructure and toughness of the heat-affected zone of samples under different t(8/5) times were monitored. According to the results, 100% bainite transformation took place in the heat-affected zone under a rapid cooling rate. The bainite content decreased, and the ferrite content increased with prolonged t(8/5). The impact toughness of the heat-affected area was shown to vary with its microstructure. The tests demonstrated that the normalised zone showed good weldability with a fine microstructure, and the impact toughness was optimised when t(8/5) of the over-heated and partial transition zones was between 10 and 15 seconds. Cooling cracks could be prevented by preheating at a temperature of 50 degrees C, and was shown using the oblique Y test. This study supports the high weldability of SA738Gr.B steel.