An efficient closed-form method for determining interfacial heat transfer coefficient in metal forming

摘要

During hot/warm metal forming processes, interfacial heat transfer between work-piece and dies has an important effect on the temperature distribution, microstructure evolution and mechanical properties of formed parts. An efficient numerical model has been developed for the determination of interfacial heat transfer coefficient (IHTC) at different forming and contact conditions. Based on FE heat transfer analysis for a typical tester, a 1D heat transfer model is proposed. A numerical procedure has been developed and implemented for determining the surface temperatures of work-piece and die, the contact heat flux, and the IHTC. The numerical model has been validated by the comparison of experimental, numerical and finite element results. For gas turbine blade hot forging process, the effects of pressure, glaze thickness and surface roughness on the IHTC of Ti-6Al-4V work-piece and H13 steel die were investigated. The application results indicated that this numerical method can provide a reliable means of predicting the IHTC in hot metal forming conditions.