Processing of heat-treated silicon carbide-reinforced aluminum alloy composites

ABSTRACT

The present study investigates the processing of heat-treated silicon carbide (SiC) particle-reinforced 6061 aluminum alloy (AA) composites. As-received SiC powders were heat treated at 1300ºC, 1400ºC, and 1500ºC in nitrogen atmosphere for 2 h, and the 6061 AA–SiC composites were developed by spark plasma sintering at 560ºC and 60 MPa for 5 min in argon atmosphere. The amorphous silicon nitride is found to form in SiC particles as a result of heating at 1400ºC. The microstructure of the composites exhibited uniform distribution of SiC or SiC/Si₃N₄ particles in 6061 AA matrix. Further, the heat-treated SiC-reinforced 6061AA composites exhibited improved mechanical properties. A typical combination of UTS of 240 MPa and elongation of 21% is obtained for the 6061 AA composites prepared using SiC powders heated at 1400ºC.

KEYWORDS:

• Aluminum
• ceramic
• particles
• composites
• sintering
• XRD
• microstructure
• morphology

Acknowledgement

B. Venkata Manoj Kumar would like to acknowledge partial support from Indian Space Research Organization (ISRO), India through project No. ISRO/RES/3/680. S.R. Meka would like to acknowledge Max Planck Society for financial support to the Max-Planck Partner Group of the Department of Microstructure Physics and Alloy Design, Max Planck Institute for Iron Research, Dusseldorf, Germany at Indian Institute of Technology Roorkee, Roorkee, India.