Fabrication of a novel hybrid AlMg5/SiC/PLZT metal matrix composite produced by hot extrusion

Abstract

A novel type of piezoelectric aluminium-based hybrid composite containing silicon carbide (SiC) and piezoelectric lead lanthanum zirconate titanate (PLZT) was prepared using powder metallurgy technique followed by sintering at 630. °C and hot extrusion at 500. °C. The volume fraction of PLZT particles varied as 0%, 5%, 10% and 15% with fixed weight 1. wt.% of SiC respectively in the composite and its effects on the microstructure as well as the damping nature of the composite were studied. The microstructure of composites was analysed by scanning electron microscope (SEM) and electron microprobe, and damping behaviour was investigated using Dynamic Mechanical Analysis (DMA) as function of temperature. Microstructural results attested the homogeneity of two different reinforcements in the composite and thus confirmed hot extrusion process had shown promising route for obtaining homogenous and dense metal matrix composites. DMA studies of homogenous hybrid MMCs indicated that the increase in wt.% of piezoelectric PLZT particles improved the damping properties.