Hydrogen Embrittlement of Titanium: Phenomena and Main Ways of Prevention

Abstract

This work deals with the issue of the deterioration of the mechanical properties of metallic materials (on an example of Ti) in the presence of hydrogen (hydrogen embrittlement). Three main forms of fracture caused by the presence of hydrogen in metallic materials are distinguished. The first one is the damage in internal pores and cracks, which appear when bubbles of gaseous hydrogen are trapped during melt solidification or hydrogen diffusion through the metal lattice. The second one is associated with hydrogen that forms hydrides and changes the type of crystal lattice of the metal. The third one includes other types of fracture associated with hydrogen in the bulk material under long-term static loads. The main methods of preventing the interaction of metallic materials with hydrogen are determined as follow: (i) alloying that reduces the rate of interaction of the metal material with hydrogen, (ii) surface modification by methods of high-energy impact, (iii) application of protective coatings, and (iv) heat treatment of final products.

Keywords

• titanium
• hydrogen embrittlement
• protective coatings
• surface modification
• structure
• hydride