Microstructural Evolution and Corrosion Behaviour of Al7075 Metal Matrix Composites Reinforced With Hexagonal Boron Nitride V. Vignesh Kumar, K. Gomathi, T. Ramkumar, B. Balasubramanian, L. Karthikeyan Materials and Corrosion, 2026 This investigation focuses on enhancing the corrosion resistance of Al7075 metal matrix composites through reinforcement with hexagonal boron nitride (h‐BN) hard‐ceramic particles. Microstructural characterisation was carried out using optical microscopy and scanning electron microscopy (SEM) coupled with energy dispersive X‐ray analysis (EDAX). The findings indicate that localised corrosion in the Al7075 matrix originates primarily at the interfaces between the matrix and h‐BN particles. A significant improvement in corrosion resistance was observed with increasing reinforcement content, particularly at 9 wt.% h‐BN, where the corrosion rate decreased to 2.743 mm/a. Post‐solution treatment further reduced the corrosion rate to 0.8169 mm/a, demonstrating its effectiveness in enhancing durability. Overall, the results confirm that solution treatment substantially improves the corrosion resistance of Al7075/9 wt.% h‐BN composites. The corrosion behaviour was systematically evaluated using Tafel polarisation in a neutral chloride medium (3.5% NaCl).
Improving mechanical and tribological performance of TiB reinforced Cu composites through microwave sintering S. Ragunath, N. Radhika, Siddabathula Mahesh, T. Ramkumar Results in Engineering, 2026 • Reinforcements of 2.5 wt.% TiB in Cu-alloy increased microhardness to 190.6 HV, a 42.4% improvement over the unreinforced alloy. • The 2.5 wt.% TiB composite exhibited a minimum wear rate of 1.324 × 10⁻³ mm³/m, showing a reduction of 40.2% compared to the Cu alloy. • TiB particles significantly enhanced both hardness and tribological performance, with 2.5 wt.% TiB reinforcements. • Surface analysis revealed wear mechanisms such as groove formation, delamination, crack propagation, and tribo-oxidation. The present work explored the effect of TiB ceramic reinforcement on the wear behavior of Cu-15Ni-8Sn (Cu alloy) composites fabricated through microwave sintering. Composites were prepared with 1.5 and 2.5 wt.% TiB and assessed for their microstructure, hardness, and tribological performance. A 2.5 wt.% TiB-reinforced composite exhibited an improved microhardness of 190.6 HV, representing enhancements of 42.4 and 17.9% over the Cu alloy and 1.5 wt.% TiB composite respectively. Wear behaviour was evaluated through Pin-on-Disc tribometer under different process parameters of applied load (10–40 N), sliding distance (500–2000 m), and sliding velocity (0.5–2 m/s). The composite with 2.5 wt.% TiB displayed a minimum wear rate of 1.324 × 10 -3 mm 3 /m at 2 m/s, which was 40.2% and 24.1% lower than the unreinforced Cu alloy and 1.5 wt.% TiB reinforced composite respectively. Worn surface analysis revealed dominant mechanisms such as crack propagation, delamination, groove formation, and tribo-oxidation. The results highlight that TiB reinforcement significantly improves the wear resistance and mechanical performance of Cu alloys making them appropriate for high-performance tribological applications.
Investigation of mechanical and tribological behavior of Al-Ni-Co-MWCNT composites prepared by powder metallurgy technique Rama Thirumurugan, M Padmanaban, T Ramkumar, D Shanmugam Proceedings of the Institution of Mechanical Engineers Part E Journal of Process Mechanical Engineering, 2026 The intended research is to improve the mechanical and tribological properties of Al-Ni-Co alloy by reinforcing the alloy with multiwall carbon nanotubes (MWCNT) using powder metallurgy. In this work MWCNT content varied from 0.5, 1.0, and 1.5 as wt. % and mixed with the Al-Ni-Co matrix. The composites are fabricated by cold compaction and conventional sintering technique. The presence of homogenous distribution was analyzed by using scanning electron microscope (SEM) with energy dispersive spectroscopy. The hardness of the composites was also explored by using Vickers' indentation and found that porosity plays a vital role and it directly influences the hardness and the mechanical properties. The wear behavior of the composites was measured using the Pin-on-Disc method at room temperature. The results revealed that 84.5Al-10Ni-4Co-1.5MWCNT possessed less volume loss (0.458 mm3) and coefficient of friction (0.45) compared to other samples. After wear analysis, the surface morphology was analyzed using SEM. The outcome of the research is MWCNT plays a vital role to improve the mechanical and tribological properties of Al-Ni-Co composites.
A review on the factors influencing natural fiber composite materials K. Koppiahraj, S. Bathrinath, P. Narayanasamy, P. Balasundar, B.K. Parrthipan, S. Senthil, T. Ramkumar Hybrid Natural Fiber Composites Material Formulations Processing Characterization Properties and Engineering Applications, 2021
