Unisothermal Austenite Decay in Electric Arc Welding

Thermal Cycle Effect on Parent Material Structure in a Welded Joint

Abstract

The thermal cycle and microstructure in each portion of the weld heat-affected zone of a steel are examined.
The CCT diagrams in the case of the max. heating temp. 1050°C for two steels, which one contain 0.27%C, 1.05%Mn, 1.3%Si, 0.3%Cr, 0.27%Ni, 0.20%Mo and the other 0.31%C, 0.63%Mn, 0.25%Si, 2.0%Cr, 0.5%Ni, 0.3%Mo, are plotted.
The microstructure and hardness in the weld heat-affected zone are in a good accordance with those of the specimen subjected to the thermal cycle of the same max. heating temp. as above (1050°C).
It seems to be reasonable to use CCT diagrams for the development of the welding technology of the low alloy and alloy steels and to be effective for the choice of the adequate welding conditions.