Seetharaman Sankaranarayanan, Subramanian Jayalakshmi, Tun Khin Sandar, Hamouda Abdelmagid S, Gupta Manoj
Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117576.
Technology Development Centre, ITE College Central, H1-01, 2 Ang Mo Kio Drive, Singapore 567720.
Materials (Basel). 2013 May 10;6(5):1940-1955. doi: 10.3390/ma6051940.
In this study, magnesium composites with nano-size boron nitride (BN) particulates of varying contents were synthesized using the powder metallurgy (PM) technique incorporating microwave-assisted two-directional sintering followed by hot extrusion. The effect of nano-BN addition on the microstructural and the mechanical behavior of the developed Mg/BN composites were studied in comparison with pure Mg using the structure-property correlation. Microstructural characterization revealed uniform distribution of nano-BN particulates and marginal grain refinement. The coefficient of thermal expansion (CTE) value of the magnesium matrix was improved with the addition of nano-sized BN particulates. The results of XRD studies indicate basal texture weakening with an increase in nano-BN addition. The composites showed improved mechanical properties measured under micro-indentation, tension and compression loading. While the tensile yield strength improvement was marginal, a significant increase in compressive yield strength was observed. This resulted in the reduction of tension-compression yield asymmetry and can be attributed to the weakening of the strong basal texture.
