Structure and Properties of the Bondage Area Between Steel and Superalloy

A superallon cast low-carbon steel to protect it from corrosion and wear. The bondage area has a complex structure: it is narrow (25-35 m wide) on the steel side and wide (250-350 m) on the superalloy’s. The part of the boundary area which is located in the superalloy consists of one sub-area and has no second-phase percipitations and two sub-areas containing various percipitations. The bondage strength turns out not to be lower than that of steel. Rupture initiates on fine second-phase particles. They contain AI, O and C distributed on the contact surface between steel and superalloy. Then rupture spreads from the contact surface into steel.