Squeeze casting technique for fabricating SiCp/Al composites with lower volume
fractions of SiC particles
fractions of SiC particles
(School of Materials Science and Engineering,
Harbin Institute of Technology, Harbin 150001, China)
Harbin Institute of Technology, Harbin 150001, China)
Abstract: A practical avenue was pointed out to fabricate SiCp/Al composites with low volume fraction by a modified squeeze casting technique in which aluminum powders were mixed into the SiC particle perform. The effects of ball milling conditions, such as rotating speed, ball milling time and the ratio of the amount between SiC particle and aluminum powder, on the size of the mixed particle were investigated. The results indicate that the distribution of SiC particles is homogeneous in the different groups of the mixed particles. The mixed particles scaled between 56μm and 125μm were used to produce preform by dry forming. The SiCp/Al composites with low volume fraction (15%) were fabricated by squeeze casting method. The microstructure of the composites was observed and analyzed by using SEM, indicating high relative density and homogeneous distribution of the SiC particles in the SiCp/Al composites. The results of tensile tests of the composites indicate that the mechanical properties of the composites are higher than those of the unreinforced aluminum matrix.
Key words: SiCp; particle distribution; SiCp/Al composites; squeeze casting