Hydrogen trap phenomena in AISI 5160 spring steel HAZ and E308-16 type austenitic stainless steel weld deposit were investigated using thermal analysis technique.
The thermal analysis peak due to the ferrite-cementite interface increased its height toward the weld deposit. The thermal analysis peak due to the microvoid was the highest where the grain size was the smallest and decreased toward the weld deposit. The thermal analysis peak due to the oxides appeared dominantly apart from the weld deposit slightly.
It was suggested that the peak appeared after heat treatment at 700℃, 10hr in unmixed weld deposit zone be due to the $\sigma/\gamma$ interface trap. In dilusion zone of weld deposit martensite structure trapped a great amount of hydrogen.
From the facts discussed above the correspondence between the cold cracking and hydrogen trap nature was also investigated.
