The main parameters involved in squeeze casting process include: applied pressure, pouring temperature, initial mold temperature and coating thickness. These process parameters have different effects on the heat transfer behavior of the interface between the casting and the die. It is of great significance to systematically study the effects of these parameters on the heat transfer behavior of the interface for controlling the casting quality and optimizing the squeeze casting process.
Based on the established method to obtain the interface heat transfer coefficient and interface pressure, a large number of squeeze casting experiments were carried out to obtain the first-hand data to study the relationship between the interface heat transfer coefficient and interface pressure. The effects of different applied pressure, pouring temperature, mold initial temperature and coating thickness on the interface heat transfer were studied.
Through a large number of squeeze casting experiments, the effects of different process parameters on the interfacial heat transfer coefficient were studied
(1) After the applied pressure, the interface heat transfer coefficient and the interface pressure almost reach the maximum at the same time; in the subsequent pressure holding stage, with the decrease of the interface pressure, the interface heat transfer coefficient decreases sharply at the initial stage, and then remains a downward trend, but the rate of decline gradually decreases; in addition, the larger the applied pressure is, the larger the average interface heat transfer coefficient is, and due to the pressure of 70 MPa The effect of interface pressure on the heat transfer coefficient is the most significant.
(2) The pouring temperature has little effect on the interfacial heat transfer coefficient and pressure;
(3) With the increase of die initial temperature, the peak value and average value of interface heat transfer coefficient increase, and the peak value and action time of pressure increase obviously.
(4) The coating thickness has a great influence on the interfacial heat transfer coefficient. When the coating thickness is thin, the effect of applied pressure on the interfacial heat transfer coefficient is obvious. When the coating thickness increases to about 125 μ m, the effect of applied pressure on the interfacial heat transfer coefficient is very small.