Author(s)

V. Bharat¹, B. Durga Prasad¹, K. Venkateswarlu²

¹Department of Mechanical Engineering, JNTUA, Anantapuramu, India.
²CSIR-National Aerospace Laboratories, Bangalore, India.

Beryllium aluminum cyclosilicate, an ore of beryllium was reinforced in Aluminum matrix to fabricate Al-beryl composites using powder metallurgy. Effect of the content of beryllium aluminum cyclosilicate on microstructural hardness and thermal expansion was studied. The coefficient of thermal expansion of Al-beryl composite was measured in the temperature range between 50^oC to 360^oC using dilatometer and was theoretically studied using thermo-elastic models, and these models were used to explain abnormalities observed experimentally. The hardness of Al-beryl metal matrix composites increased with the increase in beryl percentage. Vacuum sintering of Al-beryl metal matrix composites at 600^oC inhibited excellent bonding between the matrix and the particulate increasing the strength of the composite. The result shows the CTE significantly increased with increasing temperature but decreased with increasing reinforcement. At higher temperatures, CTE of Al-beryl metal matrix composites with 5 wt%, 10 wt% and 15 wt% of beryllium aluminum cyclosilicate was 21 ppm/K, 18.2 ppm/K, and 16.8 ppm/K. The CTE values were found to be comparable with theoretical results. The turner model showed conformance with experimental results, was well suited to the experimental results.

Al-Beryl MMCs, Powder Metallurgy, Hardness, Coefficient of Thermal Expansion (CTE), Thermo-Elastic Models

Bharat, V. , Prasad, B. and Venkateswarlu, K. (2017) Effect of Beryllium Aluminum Cyclosilicate on Thermal Expansion Behavior of Al-Based Composites. Journal of Minerals and Materials Characterization and Engineering, 5, 140-152. doi: 10.4236/jmmce.2017.53012.