FREE VOLUME CHANGE OF METALLIC GLASSES STUDIED BY THERMAL EXPANSION MEASUREMENTS

Abstract
A dilatation set up was designed and used to investigate the low temperature relaxation of amorphous Fe₄₀Ni₄₀B₂₀ and Fe₄₀Ni₄₀P₁₄B₆ through observed changes during isothermal annealing. In addition to the anticipated contraction on annealing, these amorphous alloys exhibited peaks in their dilatation curves brought about by a simultaneous but temporary expansion during structural relaxation. Although there was a considerable difference in the length change of Fe₄₀Ni₄₀B₂₀ and Fe₄₀Ni₄₀P₁₄B₆ samples, the low temperature relaxation behaviour of both alloys was qualitatively similar and the relaxation parameter could be described by an equation of the form : [MATH]