Study on the Effect of Die Coating Thickness on the Interfacial Heat Transfer Coefficient in Squeeze Casting of Aluminum Alloy

The effect of die coating thickness on the heat transfer at the metal-die interface in squeeze casting process was studied, where the interfacial heat transfer coefficient (IHTC) was determined by applying an inverse approach based on the temperature measurements inside the mold. The acquired data were processed by a low pass filtering method based on Fast Fourier Transform (FFT). The die coating used in these experiments was water-based graphite which was sprayed onto the surface of the die cavity. The die coating thickness was measured by using TT260B coating thickness gauge. The results showed that the peak and average value of the IHTC increased with the increasing of the die coating thickness when the die coating thickness was less than 32 μm. When it was more than 32 μm, the peak and average value of the IHTC decreased with the increasing of the die coating thickness. Besides, the effect of the applied pressure on the IHTC was getting smaller as the die coating thickness increased.