Effect of Heat Treatment on Microhardness and Fracture Resistance of the NWZ of a Welded Joint of Microalloyed Steel EH36 with Thickness 150 mm for Offshore Oil-Gas Platforms

Resumo

The microhardness, microstructure and susceptibility to brittle fracture with respect to the CTOD parameter are studied for industrial specimens of welded joints of sheet low-carbon microalloyed steel VL EH36 Z35² with thickness 150 mm after normalizing and subsequent post weld heat treatment. It is shown that the treatment affects positively the lowering of local microhardness and elevation of resistance to brittle fracture in the coarse-grained region of the near-weld zone of the studied type of welded joint.