In a previous study, it was shown [1] that the creep rupture life, tR, as well as the creep rupture strain, ?R, were controlled by D2 in the [D2(nGaC)] and [D2/{nt_il)] ratios (at the creep conditions of 900 °C, 300 MPa), respectively, where D is the gauge diameter, nc, the number of grains per gauge cross-section, tic the cavity (or crack) size, and / is the intercavity spacing. The theoretical models developed by Dyson and co-workers [2, 3] predicted that the creep rupture life of environmentally damaged (such as by oxidation) solid specimens is controlled only by the square of specimen section size (i.e. x D1). At the same test temperature (900 °C), oxidation would not be expected to be the important mechanism for thin-section size effect [4] for MAR-M 002. Therefore, it is concluded that the thin-section size effect is an intrinsic (or inherent) [1] property of the present relatively complex alloy (MAR-M 002), rather than an oxidation property of the material.
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