| In according to the technology curve of heat treatment of China First Heavy Machinery, temperature field simulation about the heat treatment process of turbine rotor is studied on with simulation software DeformSD, which is about to find the real temperature changes at the different location of the rotor. The result can bring process contrast between small samples and large rotor on the facet of structure and grain size changes, which offers similarity between them. It shows that the temperature field of both surface and inside change synchronously and have no exceptionality. In the following physical simulation, that is, during the experiment of small samples heat treatment, the result will be exact and reliable so long as the velocity of calefaction and cooling is slowed down and the heat preservation internal is shortened. What' s more, the temperature change from the surface to inside has the same direction except the slow velocity, and no matter that calefaction or cooling, the temperature inside will always slow and the delayed time is about lOh.During the simulation process, grain growth and structure inheritance phenomenon of the rotor steel 26Cr2Ni4MoV is studied by use of orthogonal calculation under several heat treatment process. With the note of grain size under certain condition of various calefaction and cooling method, the exact answer can be made for the previous forging stage, which helps to confer and research the grain growth and inheritance mechanism according to the metallography pictures. The experiment result shows that austenite recrystallization is one of the effective methods to eliminate structure inheritance and different calefaction and cooling method can refine grain sizeto different degree.Finally, Based on the experiment data being systemically analysed and the math model of grain growth being built,the experiment results will be a useful contribution to the simulation of grain growth(considering the grain inheritance).
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