The study of the cavity inside heavy forgings based on the temperature field detection model

In the study of improving the forging quality and the defects repairing technology, the recognition of the cavities and large cracks inside heavy forgings is a key factor. To quickly acquire the geometric parameter information of the cavities and larger cracks inside heavy forgings, firstly, based on the heat conduction theory and the cavity closure theory, a series of cavities and larger cracks are analyzed and studied. Using the three-dimensional ellipsoid model and the symbolic function, the boundary model of the cavities and large cracks inside heavy forgings is constructed. Secondly, utilizing the homogenization method of equivalent thermal resistance, the thermal conductivity is modified. And the temperature field model of heavy forgings containing the internal cavities is established. Meanwhile, the defect information of position and size is obtained and it is considered as the initial recognition condition. Thirdly, combining the temperature field and the initial boundary, the boundary recognition model of the cavities is constructed based on the recursive search method. This model is utilized to further obtain the boundary information of the forging defects. Finally, utilizing the infrared temperature measurement experimental platform and the Software COMSOL, the feasibility of the temperature field model and the cavities boundary recognition model for forging is verified. Utilizing the combination of analytical solutions and numerical solutions, the two models can be used to obtain the geometric parameters information of defects inside heavy forgings. They are significant for improving the forging quality and the defects repair.