The Design-expert software was adopted to design the response surface test with the heat transfer coefficient of each die and die temperature as the test factor and the sum of all pore volumes of the castings as the response index. ProCAST software was applied to simulate the experimental forming process

and the experimental data was obtained. Finally

the response surface test data was analyzed to obtain the influence law of heat transfer coefficient between the lower die and liquid metal on the molding quality of the castings. Moreover

water-based graphite coating and changing the coating thickness were presented to adjust the heat transfer coefficient.