Theory of amorphization kinetics in intermetallics

An examination of amorphization kinetics in intermatallic alloys indicated that both a criterion based on cascade-induced point defects and a criterion based on a uniform production of point defects rationalized observed amorphization kinetics in ion irradiated NiTi. The dose dependencies of average defect concentrations were calculated and the fluctuations in concentration were simulated using a Monte Carlo technique. Assumed low interstitial mobilities and high sink strengths promoted amorphization. Faster interstitial mobilities caused shorter lifetimes for cascades and lesser accumulation of damage. Assuming uniform production of point defects, the prediced dose exponent for amorphization increased with critical defect concentrationand increasing critical cluster size. (orig.)