Simulated heat affected zone hardness limits of C-Mn steels used in offshore structures

Abstract

The detrimental effect which hydrogen produces in metals, generally known as hydrogen embrittlement (HE), has always been one of the central problems of practical material technology of corrosion and protection of metals. In the present research, the influence of simulated heat affected zone (HAZ) hardness on susceptibility of a structural steel to hydrogen embrittlement was investigated mainly under slow strain rate testing (SSRT), although limited tests were carried out by means of small amplitude, cyclic (ripple) loading. These tests have been supported by detailed scanning electron fractography and hydrogen permeation measurements. A good correlation is observed between the degree of embrittlement in slow strain rate tests and the steady state hydrogen permeation current density.