NUMERICAL SIMULATION OF SOLIDIFICATION MICROSTRUCTURE WITH ACTIVE FIBER COOLING FOR MAKING FIBER-REINFORCED ALUMINUM MATRIX COMPOSITES

摘要

Solidification process is very important for making fiber reinforced aluminum matrix composites. Some recent studies have used cooling through reinforcing carbon fibers to obtain better control over the solidification microstructure in the post pressure infiltration process. The present work is focused on studying the effect of active cooling fiber on temperature, thermal stresses and microstructure of aluminum matrix composites. The predicted results show that the temperature gradients of both the matrix and the carbon fiber vary continuously before loading the stress field, while the temperature gradient between the fiber and Al2014 melt become steeper as a cliff after loading the stress field (when Al2014 melt solidified completely). The predicted results of temperature contour agree well with the result of references. The microstructure simulation results shows that grains grow along the opposite direction of heat flow, and form the finer equiaxed grains away from the cold end.