Temperature-dependent Ta hydride formation for recycling of Ta scraps: Experimental and thermodynamic investigations

•We report on the Ta-hydride formation depending on the temperature for recycling of Ta scraps.•Structural investigations showed that the amount of hydrogen incorporated into the Ta matrix varied with hydridation temperature.•The amount of hydrogen incorporated into the Ta matrix varied with hydridation temperature.•The H/Ta mole ratio in Ta-hydride increased with increasing the hydridation temperature up to 700 °C.

We report on the theoretical and experimental investigations about the Ta-hydride formation depending on the temperature for recycling of Ta scraps. The structural investigations based on scanning electron microscope and X-ray diffraction (XRD) showed that the amount of hydrogen incorporated into the Ta matrix varied with hydridation temperature. The XRD measurement showed that the H/Ta mole ratio in Ta-hydride increased with increasing the hydridation temperature up to 700 °C and then decreased with increasing the temperature furthermore. Depending on the hydridation temperature, various phase of Ta-hydride, such as TaH0.93 and Ta2H were formed and this hydride process was verified by thermodynamic analysis.