Effect of TiB2 Particles on the Morphological, Mechanical and Corrosion Behaviour of Al7075 Metal Matrix Composite Produced Using Stir Casting Process

Aluminium metal matrix composites are lightweight high-performance materials mostly applicable in aerospace, automobile and marine applications. In this study, the morphological, mechanical and corrosion behaviour of Al7075 metal matrix composites were investigated to find the effect of reinforcement of TiB2 particles for various weight percentage. Al7075-TiB2 composites were developed by reinforcing the 3-5 mu m size TiB2 ceramic particles using stir casting process. The particles with different weight percentage of 2, 4, 6 and 8 were uniformly reinforced with the help of the mechanical stirrer. The energy dispersive X-ray diffraction (EDAX) pattern confirms the presence of TiB2 particles in the composites. SEM and optical microstructures clearly revealed the uniform distribution of TiB2 particles in the aluminium matrix. The additions of TiB2 particles enhance the tensile strength and micro hardness due to the strong interface and load sharing between the matrix and the reinforcement particles. Dry sliding wear test was conducted by varying the applied load and sliding distance. SEM microstructure of worn surfaces shows that addition of TiB2 particles decreases the wear rate due to the presence of stiffer and stronger reinforcement particles. The electrochemical potentiodynamic polarization and salt spray test were also conducted to study the corrosion behaviour of the Al-TiB2 composites. SEM microstructures confirm the occurrence of pitting corrosion and shows that addition of TiB2 particles improves the corrosion resistance.

Automated summary

This study focused on investigating the morphological, mechanical, and corrosion behavior of Al7075-TiB2 metal matrix composites. The addition of TiB2 particles through stir casting process improved the tensile strength and micro hardness of the composites, while reducing the wear rate. Electrochemical potentiodynamic polarization and salt spray tests confirmed the enhanced corrosion resistance of the Al-TiB2 composites.