The interfacial heat transfer and pressure transmission in squeeze casting was studied through experimental and numerical approaches, especially the sensitivity to cast materials was focused via a case study on an aluminum alloy, A356, and a magnesium alloy, GW103K. The interfacial heat transfer coefficient (IHTC) at the metal-die interface was determined by employing an inverse approach based on the temperature measured inside the die. The pressure at the metal-die interface was measured by using Kistler pressure transducer. The pressure transmission in the solidification process of squeeze casting was solved by using a numerical model based on ANSYS software. The experimental results showed that the peak value and the duration time of the pressure at the casting-die interface of the aluminum alloy were higher than those of the magnesium alloy. The peak value of the IHTC of the magnesium alloy was about half of that of the aluminum alloy and the IHTC of magnesium alloy decreased more rapidly to a lower level. The numerical simulation revealed the whole process of how the solidification and mechanical properties of the materials affected the pressure transmission and the interfacial heat transfer in the solidification process. The latent heat of the aluminum alloy was higher than that of the magnesium alloy thus leading to a longer solidification time in the aluminum alloy. On the other hand, the magnesium alloy has a higher deformation resistance than the aluminum alloy under same temperature and strain rate conditions. These are the major factors resulting in the differences in the interfacial heat transfer and pressure transmission. It was also showed that these factors resulted in a higher tendency to form shrinkage defects in the magnesium alloy castings, thus higher process pressure is required for magnesium alloy castings. (C) 2018 Elsevier Ltd. All rights reserved.