Numerical Simulation of Infiltration of Carbon Fiber Preform in MMC Casting With Thermal Management

Abstract

In the casting of metal matrix composite, different processing parameters need to be controlled in order to promote the formation of primary alpha phase around the reinforcement. It has been shown [1–3] that when the reinforcement is allowed to be extended out of the cast mold and cooled by a heat sink, the microstructure of the composite can be improved due to faster heat extraction through the reinforcement. Thermal management of the reinforcement can eliminate a large portion of the eutectic phase during solidification, leading to an altered microstructure at the interface between the matrix and the reinforcement with the possibility of improved material properties. A companion paper [4] shows a comparison of the numerical simulation result of the casting of MMC by squeeze infiltration technique to the experimental work. The authors assumed that the solidification process started after the liquid metal has completely infiltrated the reinforcement. The simulation result gives a reasonable prediction to the experimentally measured cooling temperature profile. In this work, the effects of other processing parameters are analyzed to study the impregnation depth during squeeze infiltration. These processing parameters include the thermal conductivity of fibers, the initial (or preheat) mold temperature, the volume fraction of fibers, and the heat sink temperature. The study is based on the finite volume method for enthalpy formulated heat equation.