If the compression of the sample is halted before the sample is completely broken up and then held, the stress which has built up during that compression will decay. The two binary models show characteristically different types of decay behavior. In the Voigt body the stress at any instant is due partly to the strain and partly to the rate of straining. At the instant of arresting the motion the strain rate falls abruptly to zero, so that its contribution to the stress disappears, leaving only the stress due to the amount of strain, which then remains constant. In the Maxwell body the stress decays progressively, ie, relaxes, falling exponentially to zero if followed indefinitely according to the equation
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