The investigation of transient nucleate boiling is of great importance since knowledge of the laws of nucleate boiling processes are used to control phase transformations in metals. It is especially related to martensite transformations where the martensite start temperature MS is comparable to the boiling temperature of the boundary liquid layer. Since the self-regulated thermal process has been introduced, which is the main part of transient nucleate boiling where wall temperature changes very slowly and is supported at approximately the same level up to the start single-phase convection, it makes sense to use this discovery to control phase transformation in steel. It is necessary to develop a generalized equation for determination of the duration of transient nucleate boiling process.