Accurate evaluation method for thermal fatigue degradation of hot work die steel

The invention discloses an accurate evaluation method for thermal fatigue degradation of hot work die steel, provides an electron back scattering diffraction characterization method based on a physical principle, and aims at carrying out orientation parameter test and dependent variable measurement before and after thermal fatigue damage of the widely applied hot work die steel. And the thermal fatigue damage degree of the die steel is evaluated by researching the function relationship between the orientation parameter and the dependent variable of the hot work die steel. Compared with a traditional mechanical property test, the method has the great advantages that the damage process of the hot work die steel is studied from the microscopic scale through an orientation parameter method with the resolution ratio being micron, accurate numerical information is provided for the degradation degree of the hot work die steel, and the purpose of providing an accurate numerical basis for follow-up die repair can be a