Study on the Time-Varying Characteristics of In-Situ State Temperature Field of Drilled Work Piece Based on Unsteady Heat Conduction

In-Situ state heat conduction in drilling workpiece results in time-varying temperature field, which affects the final machining accuracy. From the joint action of many factors, such as geometry, material, and thermal convection characteristics, it is difficult to accurately model and describe the time-varying characteristics of the temperature field. Therefore, the time-varying model of the In-Situ state temperature field is analyzed in this paper, which lays a foundation for establishing a high-precision multi-physical field model. First, following the geometric characteristics of the drilling hole and the three-dimensional heat transfer mechanism, the heat transfer model of the drilled part is established, and the relationship between the temperature field and the physical parameters of the workpiece is characterized. Then, combining radial and axial unsteady heat conduction mechanisms, the dimensionless temperature calculation method is adopted to realize the construction of a temperature time-varying model. After that, the model parameters are revised according to the In-Situ state evolution process of the checkpoints. Finally, the experiments are carried out to calculate the credibility of the model. The results show that the prediction model is consistent with the experimental data, and the credibility of non-room temperature dynamic interval is 99.23%, which can effectively reflect the real temperature field conduction process.