Effect of particle additions on microstructure evolution of aluminium matrix composite

• Published in: Journal of alloys and compounds Vol. 525; pp. 137 - 142
• Main Authors: DURISINOVA, Katarína, DURISIN, Juraj, OROLINOVA, Mária, DURISIN, Martin
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 05-06-2012; Elsevier
• Subjects: Aluminium alloy; Applied sciences; Dislocations; Dispersion hardening metals; Dispersion strengthening; Evolution; Exact sciences and technology; Metal matrix composites; Metals. Metallurgy; Microstructure; Nanostructure; Particulate composites; Powder metallurgy; Powder metallurgy. Composite materials; Production techniques; Surface layer; Texture; Thermal stability; Aluminium alloy; Dispersion strengthening; Microstructure; Powder metallurgy; Thermal stability; Dislocation motion; Volume fraction; Metal matrix composite; Nanoparticle; Aluminium carbide; Hardness; Texture; Composite material; Dispersion strengthened metal; Grain boundary; Dislocation density; Dispersion hardening; Extrusion
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2012.02.098

► Effect of different fractions of particles on microstructure of aluminium alloy. ► Dispersed nano-particles strengthen grain boundaries at elevated temperatures. ► Particle additions provide thermal stability of matrix up to 500°C. ► Higher particle contents refine the microstructure and suppress the texture.
The study investigates the influence of different fractions of particles (1, 2.5, 5, 8 and 10vol.%) on microstructure of the as-extruded Al–Al4C3 composite as well as on the microstructure evolution at elevated temperatures and after cooling to room temperature. The results indicate that all the materials exhibit a stable microstructure up to 500°C. The excellent thermal stability is secured by the dispersed nano-particles that strengthen crystallite/grain boundaries by direct interaction of the particles with moving dislocations. In addition, the higher particle contents (8 and 10vol.%) help to suppress the deformation texture of the hot extruded solids and refine the matrix microstructure to a nanometric scale resulting in a marked enhancing of dislocation density and consequently hardness.