HIGH-TEMPERATURE HYDROGEN DIFFUSION IN ZR0.33NI0.67-H-X AMORPHOUS-ALLOYS

The proton content in Zr0.33Ni0.67-H-X amorphous alloy was monitored b y changes in electrical resistivity and with the extraplated spin echo amplitude measured by the Carr-Purcell-Meiboom-Gill (CPMG) nuclear ma gnetic resonance pulse sequence in the temperature interval 300 to 450 K. Both methods show that the hydrogen desorption processes can be app roximately divided into two ranges. The first is a fast process which is at present not interpretable. In the second stage, the process is t hermally activated, and the activation energy calcualted from the resi stivity changes is equal to 0.32 +/- 0.04 eV. The CPMG spin echo measu rements also give the spin-spin relaxation time of diffusing protons a nd the activation energy of this process, 0.34 +/- 0.02 eV, is exactly the same as extracted from the resistivity measurements.