A Leitz dilatometer was used to study the kinetics of the eutectoid reaction in the zinc-aluminum system and the effect of small additions of copper upon this reaction. Three alloys were investigated: a pure 78% zinc - 22% aluminum alloy; a 78% zinc - 21.9% aluminum - 0.1% copper alloy; a 78% zinc - 21% aluminum -1.0% copper alloy. It was found that this reaction was similar to the pearlite reaction in the iron-carbon system. The reaction occurred by diffusion processes and the products of the reaction looked similar to pearlite when examined under the microscope. Copper was found to impede the reaction by interfering with the diffusion of zinc and aluminum atoms. This effect was most pronounced at temperatures below 80° C. At higher temperatures, the copper atoms caused relatively little difference in the kinetics of the eutectoid reaction --Abstract, page ii
