Study on Liquid Metal Embrittlement of Steels (Report 1)

Penetration Behavior of Liquid Metals

Abstract

The effect of penetration of liquid metal on the flow stress and fracture properties in LME of carbon steels by Cd-5Zn, Cd-50Zn and pure Cd.was studied. Using smooth and notched specimens, experiments were conducted just above the melting points of the embrittlers, at 350°C, and crosshead rate in a tensile test was 5 mm/min.
It is shown that apart from the reduction in ductility, the stress-strain curves are slightly altered due to the grain boundary penetration of liquid metals. The results of tensile test with notched specimen also indicate that for the occurrence of LME, the stress or load has to exceed a critical value. Moreover, the mean penetration length of liquid metal at fracture could be estimated, assuming that the fracture stress of steel with liquid metal equals to the ultimate stress (i.e. actual stress) without liquid metal. The data suggest that LME can be evaluated by the mean penetration length.