Contribution of grain boundary fracture into variation of the critical brittle point of steel 15Kh2NMFA and its welds

Fracture surfaces of Charpy test pieces are studied and the proportion of grain boundary fracture is determined for 15 groups of pieces of steel 15Kh2NMFAin the state as delivered and after special embrittling treatment in the temperature range of the development of reversible temper brittleness. Welds of steel 15Kh2NMFA are studied for determining the causes of changes in the fracture energy upon formation of segregations over grain boundaries. It is shown what parameters should be allowed for in evaluation of the contribution of grain boundary fracture into the change in the critical brittle point.