PERCOLATION MODEL FOR ELASTIC SOFTENING IN INTERMETALLIC COMPOUNDS DURING SOLID-STATE AMORPHIZATION

By using isobaric-isothermal molecular dynamics and an n-body effective potential, we show that the amorphization of NiZr2, mediated by chemical disorder, is preceded by an elastic softening and begins at the percolation threshold of the strain distortion regions associated with the antisite defects. The percolation model provides a unified description of the elastic softening and loss of crystalline order in intermetallic compounds resulting from irradiation or hydrogenation.