Effect of processing parameters on the formation of composite-composite interfaces in bilayer AI/SiC_p composites

摘要

The effect of the following parameters on the infiltration height and microstructure of composite - composite interfaces created by the pressureless infiltration of superimposed SiC_p preforms by an Al alloy was investigated and quantified: processing temperature, infiltration time, preform layer height, percentage porosity and SiC particle size in the porous layers. Each of these parameters was tested at two levels: 1050 and 1250℃, 60 and 80 min, 10 mm and 20 mm, 40 and 60% porosity and, 20 and 75 μm, respectively. Results indicate that the interaction between porosity and preform layer height is the parameter that most significantly impacts the formation of a composite - composite interface and that infiltration time is the parameter that most significantly affects the formation of unwanted phases at the composite - composite interface. The optimum parameters for maximum height of infiltration and formation of a composite-composite interface are: 1250℃ and 60 min, using 20 μm particles in 60% porosity preforms (10 mm high) and 75 μm particles in 40% porosity preforms (20 mm high).