AB2-based metal hydrides have been studied in order to find high-capacity, low-hysteresis alloy-hydrogen systems for high-pressure applications with strict thermal boundary conditions. TiCrMn1-3xFe2xVx (x=0, 0.05, 0.1, 0.15 or 0.2) and Ti1-yZry(CrzMn1-z)2 (y=0.05 or 0.15 and z=0.5 or 0.6) alloys have been synthesized and characterised by XRD, ICP spectrometry and volumetric PCI measurements. In addition, the PCIs of two commercial (GfE) alloys, Hydralloy C2 and Hydralloy CO, have been measured and a PDSC study on Hydralloy C2 has been performed, in order to assess the feasibility of their basic hydriding properties for narrow temperature interval applications. In the Fe and V containing alloy-hydrogen systems, hysteresis can be overcome at the cost of reduced hydriding capacity, while in the Zr-containing hydrides, at the temperatures of this study (-80 to 60°C), hysteresis is not completely eliminated but the hydriding capacity remains good also at high temperatures. The interplay between these properties of hydrides is discussed, as well as the role of materials characteristics in specially constrained applications.
- High-pressure hydride
- Thermal boundary conditions