Welding of defects in cast cases of turbines with perlite electrodes without heating and thermal processing

The regularities of structural formation of the weld metal and HAZ during multilayer welding, made by the transverse humping method, with short sections of defects on cast steel 15Kh1M1FL with perlite electrodes without heating and heat treatment are considered. It has been established that the structure of all the studied zones of the welded joint is represented by upper granular bainite of varying degrees of dispersion. The difference in the hardness of the structures in the upper and middle parts of the welded joint is insignificant (3I4 and 296 HV, respectively). In the upper part, the formation of a hypereutectoid ferrite is found, which is located along the grain boundaries, which is also related with edge effect. The plastic properties of the weld metal are increased by more than 1.5 times, KCV – by more than 3 times in comparison with the base metal. (author)