A Hydrogen Embrittlement is the process of less resistant and ductility in tensile strength of a metal caused by the presence of hydrogen.
Reference Definition by NACE: A Hydrogen Embrittlement is a type of deterioration which can be linked to corrosion and corrosion-control processes. It involves the ingress of hydrogen into a component, an event that can seriously reduce the ductility and load-bearing capacity, cause cracking and catastrophic brittle failures at stresses below the yield stress of susceptible materials. Hydrogen embrittlement occurs in a number of forms but the common features are an applied tensile stress and hydrogen dissolved in the metal. Examples of hydrogen embrittlement are cracking of weldments or hardened steels when exposed to conditions which inject hydrogen into the component. Presently this phenomenon is not completely understood and hydrogen embrittlement detection, in particular, seems to be one of the most difficult aspects of the problem. Hydrogen embrittlement does not affect all metallic materials equally. The most vulnerable are high-strength steels, titanium alloys and aluminium alloys.
Related Definitions in the Project: The Metallurgy (Corrosion and Cracking)
