Synthesis, Characterisation and Mechanical Behaviour of In-situ Al7SiMg/TiB 2 Composites Prepared by Salt-Metal Reaction

• Published in: IOP conference series. Materials Science and Engineering 2020-08, Vol.912 (5), p.52018
• Main Authors: Oommen, Niranjan, Ajayan, Sanjay, Sundaraman, Chellam, Sasikumar, S
• Format: Article
• Language: English
• ISSN: 1757-8981; 1757-899X
• DOI: 10.1088/1757-899X/912/5/052018

Aluminium based lightweight-high strength metal matrix composites are widely used in applications such as automotive, military, and aerospace because of their improved physical, thermal and mechanical properties. In this work, the synthesis, structural and mechanical characterisation of Al7SiMg/TiB 2 composites prepared by the in-situ route was studied. The composites with different amounts (4 and 9 wt. %) of TiB 2 particles were developed as a result of the reaction between the molten alloy and the K 2 TiF 6 and KBF 4 salts at 810 °C. These composites were examined by XRD and SEM/EDS. The elemental phases present in the composite and presence of TiB 2 were confirmed by XRD results. SEM micrographs showed the formation and distribution of micron-sized TiB 2 particles mostly along the grain boundary of the alloy matrix. The structure of TiB 2 particles was hexagonal. The effect of TiB 2 content on the hardness and wear resistance was investigated by using Vickers hardness tester and Pin-on Disc apparatus at room temperature. Increased hardness indicated increased wt. % of TiB 2 particles in the composites. The wear data indicated the amount of TiB 2 particles influence wear rate and mass loss values, while wear rate and mass loss of material increase with applied normal load and sliding distance.