Studying the Effects of Welding Heat Input on CGHAZ of Q370qE Steel Plate
The thermal cycle process simulation test is carried out on 20 mm thick Q370qE steel plate at different welding heat inputs by means of Gleeble-3500 thermal simulation testing machine,the variation law of the microstruc-ture in the welding coarse grained heat affected zone(CGHAZ),the sectional Vickers hardness and impact property at different welding heat inputs are studied.The test shows that with the increase of welding heat input and microstructure coarsening,the Vickers hardness and impact absorbed energy value at the CGHAZ keep decreasing.Within the values ranging from 30 kJ/cm to 100 kJ/cm,with the increase of the welding heat input,the test steel plate shows a tendency of slow decline for the impact toughness at CGHAZ,which is related to the prior austenite grain refined by the ferrite in grain.