Creep fracture phenomena in iron embrittled by liquid copper

Tensile creep studies of the embrittlement of notched iron by liquid copper in the range 1100 to 1130° C have shown the embrittlement to be of the delayed failure type, from diffusion-controlled, grain boundary penetration by copper with accompanying extended surface notching. Linking of surface cracks and internal cavities along copper-penetrated grain boundaries was the final failure mode. Crack growth was determined by the rate and amount of copper diffusion ahead of a crack and not by the feed of liquid to the crack tip.