Accession Number : AD0718825

Title :   Ternary Diffusion.

Descriptive Note : Technical rept.,

Corporate Author : FLORIDA UNIV GAINESVILLE DEPT OF METALLURGICAL AND MATERIALS ENGINEERING

Personal Author(s) : DeHoff,Robert T. ; Guy,Albert G.

Report Date : 1969

Pagination or Media Count : 86

Abstract : Tracer diffusion coefficients were determined for the three isotopes, Zn65, Cu67, and Ni66, in homogeneous copper-nickel-zinc binary and ternary alloys as a function of composition, to 30% nickel and zinc, and as a function of temperature, within about 250C of the solidus surface. Activation energies and D sub o factors were determined as a function of composition from these measurements. It is found that as the composition plane is traversed in the general direction from higher nickel compositions on the copper-nickel binary to high zinc concentrations on the copper-zinc binary, i.e., as nickel is replaced by zinc, the diffusivity of all three tracers increases, and the activation energy for diffusion decreases. The total change in diffusivity across the composition plane is about two orders of magnitude. The three diffusivities are always in the order: D* sub Zn>D* sub Cu>D* sub Ni, with the ratio being 9:3:1 at 900C for all compositions. The three activation energies are usually in the order Q* sub Ni>Q* sub Cu>Q*n. These results are shown to be consistent with atom size and electron-to-atom concentrations of the three species in this alloy system. (Author)

Descriptors :   (*COPPER ALLOYS, *DIFFUSION), NICKEL ALLOYS, ZINC ALLOYS, TRACER STUDIES, HEAT OF ACTIVATION, COPPER, ZINC, NICKEL

Subject Categories : Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE