Experimental Study and Numerical Verification of Heat Transfer in Squeeze Casting of Aluminum Alloy A443

Abstract

As an effective tool, simulation helps do the analysis and optimization in advance and undertake preventive action. A critical portion of casting simulation is the heat transfer at the metal/mold interface. However, it is difficult to determine the values of interfacial heat-transfer coefficients (IHTCs) in squeeze casting of aluminum alloys due to many influence factors. In this work, IHTCs were determined by using the inverse algorithm based on measured temperature histories and finite-difference analysis in a five-step squeeze casting of aluminum alloy A443. The results showed the IHTCs initially reached a maximum peak value followed by a gradually decline to a lower level. Similar characteristics of IHTC peak values were also observed at 30, 60, and 90 MPa applied pressures. With the applied pressure of 60 MPa, the peak IHTC values of aluminum alloy A443 from steps 1 to 5 varied from 5629 W/m2K to 9419 W/m2K. The comparison of the predicted cooling curves with the experimental measurement manifested the cooling temperatures calculated by the IHTC values determined in the current study were in the best agreement with experimental ones. The verification of the determined IHTC values demonstrates that the inverse algorithm is an effective tool for determination of the IHTC at the squeeze casting–die interface.