Liquid metal embrittlement of an austenitic 316L type and a ferritic-martensitic T91 type steel by mercury

The susceptibility to liquid metal embrittlement (LME) of 316L and T91 steels by mercury has been studied at room temperature. A dedicated experimental device using center crack tension (CCT) specimens was built. We developed a specimen preparation procedure that must be rigorously applied in order to investigate the embrittling effect of Hg. The high strength ferritic-martensitic steel of type T91 is embrittled by Hg at room temperature over a large range of crosshead speeds,, between 6.67 x 10(-7) and 6.67 x 10(-3) m s(-1). More surprisingly, the austenitic steel of type 316L is also embrittled by Hg between 1.67 x 10(-8) and 2.5 x 10(-4) m s(-1). The fracture of the T91 and 316L CCT specimens in contact with Hg occurs by shear band decohesion over the above-mentioned range of crosshead speeds. (C) 2008 Elsevier B.V. All rights reserved.