To accurately calculate the mould temperature field during the spray process of die casting process

the interfacial heat transfer coefficient（IHTC） between the mould and the spray medium is an extremely important thermo-physical parameter. A spray experiment was conducted with different spray pressures

in which the temperature history throughout the spray cooling process of H13 steel plate was recorded. The IHTC at the different spray pressures was calculated by utilizing the nonlinear estimation method. The interface morphology and heat transfer characteristics within the spray cooling process were investiagted

and the influence of spray pressures on the IHTC was expounded. The results show that the interface can be divided into wet and dry zone

where the former significantly affects the heat transfer behavior on the interface. It is found that high spray pressure has a positive effect on improving peak IHTC

whereas it impedes the expansion of wet zone and delays the peak of IHTC.