Effect of electroceramic particles on damping behaviour of aluminium hybrid composites produced by ultrasonic cavitation and mechanical stirring

• Published in: Materials & design 2015-11, Vol.84, p.110-117
• Main Authors: Montalba, C., Eskin, D.G., Miranda, A., Rojas, D., Ramam, K.
• Format: Article
• Language: English
• Subjects: Aluminum base alloys; Casting; Cavitation; Ceramics; Damping; Dispersions; Hybrid metal matrix composite; Mechanical stirring; Particulate composites; Piezoelectric; Scanning electron microscopy; Silicon carbide; Ultrasonic cavitation; Wettability
• ISSN: 0264-1275; 1873-4197
• DOI: 10.1016/j.matdes.2015.06.101

In this study, electroceramics PBN and PLZT along with SiC were included in Al–3.96wt.%Mg (A514.0) master alloy. Ultrasonic cavitation (UST) and mechanical stirring (MS) were employed to improve wettability and dispersion during casting. Two composite systems were produced: PBN system (5wt.% PBN+1wt.% SiC and 15wt.% PBN+1wt.% SiC) and the PLZT system (follows the same designation). The influence of fabrication method on the microstructures, particle distribution and wettability as well as electroceramic impact on dynamo-mechanical properties of prepared composites were investigated. Optical microscope (OM) and scanning electron microscope (SEM) results indicate that the processing technique was effective as it promoted wettability and homogeneous dispersion of particles throughout the Al matrix. Dynamic mechanical analysis (DMA) study of the composites demonstrated that the addition of the functional particles to the Al alloy matrix improved damping capacity (Tan δ) at 200°C. The composites exhibited an increase in Tan δ of 24.3±0.3% and 91.4±0.2% for 5 and 15wt.% PBN+1wt.% SiC and an increase of 19.7±0.5% and 42.5±0.3% for 5 and 15wt.% PLZT+1wt.% SiC, respectively, when compared to the aluminium alloy matrix. [Display omitted] •Hybrid metal matrix composites with electroceramics and SiC particles were fabricated.•Particles were added in the melt via ultrasonic cavitation and mechanical stirring.•Particles achieve good dispersion and excellent wettability with aluminium matrix.•Damping exhibits an ample increase with the inclusion of piezoelectric particles.