Interstitial N diffusion under low energy (≈700eV) Ar+ bombardment at 673K in ion-beam nitrided austenitic stainless steel was investigated. Ar+ ion bombardment increased the N mobility in depths far beyond the ion penetration depth, resulting in an increased broadening of the N depth profile as a function of Ar+ flux. This effect could not be explained by any established mechanism of radiation-enhanced diffusion. An explanation based upon quasi-particle-enhanced mobility was proposed.

Anomalous Ion Accelerated Bulk Diffusion of Interstitial Nitrogen. G.Abrasonis, W.Möller, X.X.Ma: Physical Review Letters, 2006, 96[6], 065901 (4pp)