Hydrogen embrittlement of a TiAlZr alloy evaluated by impact test method

The characteristics of hydriding and hydrogen embrittlement of a TiAlZr alloy were evaluated by the impact test method. The results indicated that the hydrides in TiAlZr alloy formed as platelets and were identified as face-centered cubic δ-hydride. At room temperature, the specimen showed great sensitivity to embrittlement in ductility by hydrogen. The hydrides formed promoted the crack propagation in the presence of stress, leading to the cleavage failure mode. The impact toughness decreased dramatically with increasing hydrogen concentrations, indicated that the critical hydrogen concentration required to embrittle the alloy might be lower than 300 ppm.