A simple model, based on thermoelastic force balance, is suggested for the part of the stabilization of martensite resulting from pinning of interfaces, which is complementary to atomic reordering. A simple static solution is obtained for the overheating required to initiate the motion of an interface, pinned by quenched-in defects. Qualitative analysis of the pinning-induced stabilization in polyvariant sample is performed, assuming fractal fragmentation of variant structure. The model predicts that: shift to higher temperatures and broadening of the reverse transformation range occurs during pinning-induced stabilization; if the reverse transformation remains complete, pinning-induced stabilization does not break the thermoelastic sequence of the transformation; kinetics of shift and broadening of the reverse transformation can be different; the shift of the reverse transformation start temperature first reaches saturation value, whereas the increase of the transformation finish temperature is a more long-term process. Numerical estimates show that pinning can easily account for the experimentally observed values of the thermal stabilization ofmartensite.
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