Hydrogen Permeation and Hydrogen-Induced Cracking

This chapter describes hydrogen permeation and hydrogen-induced damage in metals and alloys. The chapter discusses hydrogen evolution kinetics, theoretical diffusion solutions, and basic hydrogen permeation models. Models are used as a diagnostic tool to determine various metal and alloy effectiveness as hydrogen permeation inhibitors. It then explains experimental atomic hydrogen permeation transient determination and hydrogen absorption rate constants and diffusivity evaluation into metals through case studies. A discussion on hydrogen embrittlement, hydrogen-induced cracking (HIC), hydrogen blistering, and hydrogen stress cracking is included to show the relationship to hydrogen permeation and HIC mechanisms previously described in the chapter. The most recent research related to hydrogen kinetic parameters is reviewed in the chapter. The case studies and solved problems illustrate models to develop alloys that reduce hydrogen ingress.