Tracer Diffusion in the Ni-CoCrFeMn system: Transition from a dilute solid solution to a high entropy alloy

Kottke Josua, Laurent-Brocq Mathilde, Fareed Adnan, Gaertner Daniel, Perrière Loïc, Rogal Łukasz, Divinski Sergiy, Wilde Gerhard

Abstract

Tracer diffusion of Co, Cr, Fe and Ni is measured at 1373 K in Co20Cr20Fe20Mn20Ni20, Co10Cr10Fe10Mn10Ni60 and Co2Cr2Fe2Mn2Ni92 alloys. Diffusion retardation in the high-entropy Co20Cr20Fe20Mn20Ni20 alloy is most prominent in comparison to the Co2Cr2Fe2Mn2Ni92 solid solution, however the concept of ‘sluggish’ diffusion cannot be used as a blanket statement. The tracer diffusion coefficient drops either slightly (by a factor of three, Fe) or marginally (by a factor of 1.2, Ni) if compared at 1373 K. Alternatively, if compared on a homologous temperature scale, the diffusion retardation can be as large as a factor of 30 (Fe) or 10 (Ni).