TEMPERATURE-DEPENDENCE OF GRAIN-GROWTH IN ZONE-REFINED TIN CONTAININGLARGE ADDITIONS OF ZINC IN SOLID-SOLUTION

Grain growth in zone-refined tin containing high concentrations > 0.05 < 0.40 wt% Zn in solid solution have been investigated in the tempera ture range 70-160-degrees. It has been found that increasing the zinc content by a factor of 8 decreased the rate of grain growth by approxi mately 30% at all annealing temperatures, and this was attributed to s mall variations of grain boundary mobility. In addition, the increase of annealing temperature from 70 to 160-degrees-C resulted in the incr ease of grain growth by a factor of approximately 50 at any given conc entration, which shows that the rate of grain growth is not strongly i nfluenced by increasing the zinc concentration. The energy activating the growth process was calculated for all concentrations investigated and had a nearly constant value of approximately 1 eV. An empirical fo rmula was proposed relating the rate of grain growth and the solute co ncentration.