On the Kinetics of the Order-Disorder Transformation in Cu3Au

1 November 1940

journal article
conference paper
Published by AIP Publishing in The Journal of Chemical Physics

Vol. 8 (11) , 860-866
https://doi.org/10.1063/1.1750595

Abstract

Using the elastic modulus S₁₁ as an indicator, the rate of the order‐disorder transformation of Cu₃Au has been investigated in the region near the critical temperature. The variation of S₁₁ with time, at constant temperature, of a [100] single crystal of the alloy has been measured, and all the data for the transformation from disorder to order can be represented in one curve by plotting the fraction of untransformed material against the ``reduced'' time, t/τ. The relaxation time τ decreases rapidly with increasing amount of undercooling below the critical temperature, and combined with the data of Sykes and Evans on the resistivity vs. time curves, points to a minimum in τ about 20°C below the critical temperature. The critical temperature for the ordering process was found to be 386.8°C, for the disordering process 388.0°C. The observed data on the variation of τ with temperature are discussed in terms of a mechanism of nucleation and growth for the transformation.

Keywords

This publication has 3 references indexed in Scilit:

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Physical Review B, 1940
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