Enhancement of fracture toughness of high-strength Cr–Ni weld metals by strain-induced martensite transformation

The effect of strain-induced martensite transformation from retained austenite was investigated on the fracture toughness of Cr–Ni weld metal, in terms of crack tip opening displacement, within the range of room temperature to 77 K. Strain-induced martensite transformation has a positive impact on fracture toughness and can change fracture mode. This effect generally increases with an increase in the amount of retained austenite, but it is weak at 77 K.