Deformation mechanisms in a new disc superalloy at low and intermediate temperatures

The deformation microstructures of a new disc superalloy, TMW-4M3, have been investigated by transmission electron microscopy at temperatures ranging from 25 to 725 °C. Dislocation pairs cutting was the dominant mechanism at 25 °C, whereas stacking faults and deformation twinning were the main mechanisms at 650 and 725 °C, respectively. The factors that affect the transition of deformation mechanisms are discussed. The deformation processes involving planar defects may enhance the yield strength of TMW-4M3 at intermediate temperatures.

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