Effect of Mechanical Mould Vibration on Solidification Behaviour and Microstructure of A360-SiC_p Metal-Matrix Composites

Abstract

In this work the microstructural evolution of an A360 alloy reinforced with 10vol.% SiC particulate is described. During the material solidification, mechanical vibration, in the range of 0-41 times the gravity acceleration, g, has been applied to a steel die. It has been observed that vibrations can promote a quite homogeneous SiC dispersion on macroscopic scale. On the other hand, by using too high vibrations’ intensity, segregation phenomena have been pointed out in the castings. Furthermore, it has been evidenced that the reinforcement distribution is influenced by mechanical entrapment of the particles at grain boundaries and in the interdendritic channel. The metallographic analysis has emphasized a finer microstructure with increasing vibrations’ intensity. By comparing simulated and experimental temperature curves of the mould in the different cases, different HTC made the best fit. By increasing the vibrations’ intensity, the HTC increases in the temperature range of solidification of the composite.

Microstructural Changes and Quality Improvement of Al7Si0.2Mg (356) Alloy by Die Vibration

“…This is due to the forced convection effect induced by die vibration, which increased the heat transfer coefficient. It is reported that the heat transfer coefficient of casting A360-SiCp composites in stationary die was in the range of 1000-2700 W/m 2 K and that with intensity of die vibration of 29 g was in the range of 1000-10,000 W/m 2 K. 29 It is well known that higher heat transfer coefficient during solidification increases undercooling, which consequently refines microstructure and reduces microsegregation of solutes in a-Al phase.…”

Response analysis of a continuously-cast billet under the impact vibration of the solidification end

“…As an effective research method, numerical simulation is widely used in various fields. Some scholars have used commercial software to simulate the temperature field and flow field of ingots under the vibration condition, which effectively supplements the theory of improving the quality of ingots with vibration technology [7][8][9][10]. However, simulation studies on the impact vibration applied to the solidification end of the continuously-cast billet are rare.…”