Cracking resistance of welded joints of different steels

Welded samples made of the 38KhN3MFA and 15Kh5MF steels with the 10Kh25N13G2 type welded joints (O3L-6 electrodes) are tested both in initial and tempering state. Existence of diffusion and crystallization interlayers of increased hardness is shown to result in brittle fracture along a fusion zone in the certain temperature range. Growth of width and hardness of interlayers leads to widening of the indicated temperature range, thus increasing the transition temperature of brittleness for a welded joint of different steels and decreasing sharply its cracking resistance