Role of Surface Processes in the Gaseous Hydrogen Embrittlement of Steels

摘要

A brief overview of the gaseous hydrogen embrittlement (ghe) of iron-based alloys is presented. The central theme of the review is concerned with identifying the role of surface processes and exploiting this knowledge in the determination of bulk characteristic length scales associated with the phenomenon. In this regard, adsorption is shown to be the rate limiting process in ghe during Stage II crack growth in high strength steels. We also take this opportunity to clear up some misconceptions which have developed in the literature of this topic with regard to adsorption aspects of embrittlement. Here we consider the role of oxygen as an embrittling agent and limitations inherent in adsorption isotherms, often used in the calculation of reductions in surface free energy. Finally we consider some related work which we hope serves to illuminate our approach in studying gaseous hydrogen embrittlement. 28 references. (ERA citation 10:013351)