Study of Hydrogen Induced Embrittlement of Ti-Al-Zr Alloys

The tensile and impact tests of the cathodic charging Ti-Al-Zr alloy were measured with the hydrogen concentration up to 1200 μg/g in order to study the behavior of hydrogen in titanium alloys.The results showed that the strength of the alloy had increased and this was the result of solid solution strengthen-ing.The total elongation exhibited a negative dependence on the hydrogen and decreased with the hydrogen monotonically from ~30% to 22% in the range.The absorbed energy also exhibited a negative dependence on the hydrogen and decreased by 80% at ~300 μg/g,which reflected that this alloy had much sensitivity to em-brittlement by hydrogen even in the slight increase of hydrogen content.The fracture characteristics for the tensile and impact specimens were analyzed,and it showed that there existed a lot of large secondary cracks in the impact specimens,and the fracture mode was changed from ductile to cleavage as the hydrogen content increases.However,there only had some small secondary cracks in the tensile specimens.