Free forming of locally induction heated specimens

Okman, Oya
Hot forming is highly utilized in manufacturing of complex shapes. Relatively low flow stresses of materials at elevated temperatures provide ease of manufacturing. On the other side, the current trend is to replace hot forming with cold forming due to the superior mechanical properties and higher dimensional accuracy of the products and less energy consumption. However, cold forming requires high tooling costs and forming loads. In this study, a new process is proposed for production of complex shaped products where the disadvantages of both of the alternatives are tried to be minimized. The basic idea is to control the mode of deformation by heating the specimen locally prior to forming. Electromagnetic induction is used for local heating. Numerical simulations are carried out by finite element method (FEM) for further investigation on the effect of parameters. Thermo-mechanical analysis of heat diffusion and upsetting is supported by electromagnetic analysis of induction heating. The failure modes and operational window of the novel process is established. Conclusions are drawn on the applicability of the process and the effect of process parameters on the efficiency.


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Citation Formats
O. Okman, “Free forming of locally induction heated specimens,” M.S. - Master of Science, Middle East Technical University, 2005.