Hydrogen distribution and hydrogen cracking susceptibility of a martensitic-austenitic steel welding wire

Hydrogen distribution and cracking susceptibility of a martensitic-austenitic steel weld in ambient atmosphere and in aggressive chemical environment was evaluated by measuring hydrogen desorption at a constant heating rate. In ambient atmosphere, most of the hydrogen is trapped in austenite phase, thus the weld is not susceptible to hydrogen cracking. In chemical environment, diffusible hydrogen content of the weld is much higher than the critical hydrogen level to cause cracking, thus weld metal is highly susceptible to hydrogen cracking.