M. Wanner et al., THERMODYNAMIC AND STRUCTURAL-CHANGES OF VARIOUS INTERMETALLIC COMPOUNDS DURING EXTENDED CYCLING IN CLOSED SYSTEMS, Journal of alloys and compounds, 253, 1997, pp. 692-697
The application-relevant AB(5)-type intermetallic compounds LmNi(4.85)
Sn(0.15), LmNi(4.49)Co(0.1)Mn(0.205)Al(0.205) and LmNi(4.08)Mn(0.62)Al
(0.1)Co(0.2) underwent about 90 000 thermally induced hydrogen absorpt
ion-desorption cycles in closed systems at different cycling temperatu
res and pressures. Depending on the individual rates of decay, regener
ation procedures were carried out several times. After the half time a
nd after the end of cycling additional experimental techniques were em
ployed in order to determine possible structural and stoichiometric ch
anges. Among these X-ray powder diffractometry, magnetization, scannin
g electron microscopy including EDX and thermal desorption spectroscop
y were utilized. Besides the degradation behaviour of each material, n
ew results are presented about the degradation phenomena (structural c
hanges, disproportionation) and a comparison is given of various regen
eration procedures.