Effect of composition of B₄C-aluminum composites on mechanical properties and resistance corrosion

Purposes of this work were to define the compositions which allowed removal of specimens from the die after pressing without crumbling, the only compositions which made this possible were those containing 3%, 5% and 7% in weight of B₄C (the rest was aluminum), and to determine the effect that B4C content has on the mechanical properties of the composites, resistance to corrosion, and examination by optical and scanning microscopies. Samples were prepared by a P/M technique. Compression properties were better in the composites than in aluminum and improved with carbide content. Samples of all the experimental compositions subjected to salty steam within a salty steam chamber did not show any corrosion. Optical microscopy revealed that Al and the composites have a like cell structure. Scanning microscopy revealed that morphology of the B₄C particles is polyhedral. There were identified also particles of SiC and A1₂O₃, coming probably from the mill.