The Beck's nonlinear reverse estimation method is a robust and accurate method for identifying the IHTC in hot stamping operations. The error between the estimated and measured die surface temperatures is less than 5%.

The IHTC correlates highly with contact pressure by a positive power function. The IHTC increases rapidly with decreasing surface roughness when Ra > 1.0 μm, but when Ra < 0.9 μm, the pace slows down and the IHTC tends to saturate, especially under high contact pressure.

The IHTC of #45-tool-steel is about 2.1 times that of H13-tool-steel. Among the material thermo-physical properties, the thermal conductivity and specific heat capacity are the primary influencing factors on the IHTC.

The martensitic transformation yields a positive gain on IHTC by approximately 30%. The combination of phase transformation induced thermal conductivity increasing and latent heat releasing results in a sharp increase of the IHTC near the Ms point.

Although the oxidation preventive oil coating can reduce oxidation of the blank, it reduces the IHTC significantly. Under the same contact pressure, the IHTC of the 22MnB5 blank coated with 42-μm thick oil is about 1/3 that of the bare blank. The IHTC decreases more with a thicker coating.