Microstructure and properties of hydrogenated TB8 alloy

Thermohydrogen processing can enhance workability, decrease flow stress and deforming tempera- ture of titanium alloys. In this study, thermohydrogen processing was carried out for metastable β-type TB8 alloy. The microstructures of hydrogenated TB8 alloy were investigated based on scanning electron microscopy （SEM）, transmission electronic microscopy （TEM） as well as X-ray diffraction （XRD） analysis. The results reveal that 6 hydride phase forms in the hydrogenated TB8 alloy, but the amount of β phase increases with hydrogen content increasing. Single β phase appears when the hydrogen content reaches 0.7 wt%. The alloying elements redistrib- ute in the hydrogenated TB8 alloy, and hydrogen leads to the reduction of the alloying elements in β phase. The room-temperature compression tests were performed on a MTS809 machine. It is found that the room-temperature yield strength of hydrogenated TB8 alloy decreases. And minimum yield strength is obtained at a hydrogen content of 0.5 wt%. The ductility does not decrease within 0.7 wt% hydrogen content. These results provide theoretical basis for improving the formability and promoting the applica- tions of TB8 alloy.