Damping behaviour of cast and sintered aluminium

Abstract

Estimating damping in structures made of different materials and processes still remains as one of the biggest challenges. Aluminium is one such pioneer material which is being used extensively in aerospace, automotive and the manufacturing industry. Aluminium components are mainly manufactured by traditional casting and powder metallurgy process. The main objective of this paper is to estimate the damping ratio of aluminium manufactured through powder metallurgy (P/M) process and compare it with the commercially available Cast aluminium. Aluminium powder is compacted, sintered and then it is extruded to the required geometry. Cantilever beams of required size and shape are prepared for experimental purpose and the damping ratio is investigated. Damping ratio is determined by sweep sine test using half power bandwidth method. Free vibration tests also confirmed the damping ratios obtained by sweep sine method. It is observed that damping ratio is higher for sintered aluminium than cast aluminium which may be attributed to increased porosity. © 2006-2009 Asian Research Publishing Network (ARPN). All rights reserved.