Abstract
An overpressurized bubble in an amorphous material (iron) is simulated, using a two-body potential method. Values for the surface energy γ of the bubble and the shear modulus μ of the material are derived. It is found that the excess pressure P exc at which gas bubbles grow under noble-gas implantation is of the order of μ/6 (∼ 75kbar). This value is of the order of the theoretical shear strength in crystalline metals. The calculated P exc is considerably larger than that observed in crystalline materials with the same μ value. The radius of He bubbles as a function of the implanted dose in an amorphous alloy is calculated, using the numerical results for γ and P exc, and using the constant-excess-pressure growth model. The agreement with the experimental results is good, other experimental facts also confirm the numerical results of the simulation.