Processing and characterization of Cu-Al2O3 and Al-Al2O3 composites: an evaluation for micro- and nano- particulate reinforcements

摘要

Composites are formed by the physical association of matrix and reinforcement and possess intermediate properties of the components’ it is constituted of. Metal matrix composites (MMCs) reinforced with ceramic particles furnishes ductility along with strength and has been into practice since decades. The applications cater the aerospace and automobile industries such as turbine rotatory machinery components, rocket turbine housing, cryostat, cryo-pump impeller and cryo-pump inducer. Powder metallurgy has been a conventional still inevitable technique to serve the automotive and aerospace industries with components of utmost importance. The powder metallurgy process consists of several steps which are crucial to the end products’ properties. This work aims at investigating some of the steps to assess the microstructure and properties of copper and aluminium based composites varying the reinforcement particle size and volume fraction. Structural integrity is a vital factor of a composite which accounts for the physical intimate bonding of matrix and reinforcement. This factor varies with the fabrication parameters and techniques which are also fundamental for effective stress transmissibility from matrix to reinforcement. Structural integrity of a composite material also fluctuates within the service life of the material, for eg. during harsh and hostile environment thermal exposures.