Investigation of the coarse grained heat-affected zone microstructure and hardness of multipass welded X65 linepipe steel.

In this thesis the effect of single and multipass welding on the microstructure and hardness of X65 linepipe steel of four different chemical compositions was investigated. The welding was simulated for three different heat inputs and two second pass peak temperatures. The thermal simulation has been achieved by simulating the CGHAZ with a...