This work explores the mechanical, thermal, and tribological characteristics of carbon fabric reinforced epoxy (CF-Ep) composites filled with halloysite nanotubes (HNT). The mechanical properties were evaluated, including hardness, interlaminar shear strength (ILSS), tensile strength, and flexural strength. The enhanced curing and even dispersion of HNTs in the epoxy matrix were validated by DSC, FTIR, and SEM measurements. Thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA) demonstrated improved thermal stability and damping, especially for the 0.75 wt.% HNT composite. Tribological performance was investigated utilizing a pin-on-disc configuration (60 N, 3 m/s) and silica sand (212 µm, 30 N, 2.38 m/s) under three-body abrasion and dry sliding wear, respectively. Hardness was highest at 1.75 wt.% HNT, and wear resistance and mechanical performance were best at 0.75 wt.% HNT composite. Surface damage, including matrix separation, micro-ploughing, and fragmentation, was lessened in 0.75 wt.% HNT composites, according to scanning electron microscopy worn surfaces. Using Minitab 17 and the Taguchi approach, wear experiments was created using an L16 orthogonal array. There were four levels of variation in three factors: load (10–40 N), abrading distance (250–1000 m), and HNT content (0–2.75 wt.%). The most important variables influencing wear volume loss were found to be load + distance and load + filler interactions using ANOVA and regression analysis. Scanning electron microscopy revealed that H0.75% HNT-filled composites had the best resistance to wear because they showed less surface damage mechanisms, such as fragmentation, micro-ploughing, and matrix detachment, when they were worn-out by dry sliding or abrasion. Overall, by strengthening interfacial bonding, improving load transfer, and creating a protective tribolayer that decreased material loss and surface damage during abrasion, HNTs improved mechanical and wear properties. Specifically, the 0.75 wt.% HNT composite showed outstanding heat stability and wear resistance, which made it a good option for high-performance uses such as power plant chute and automobile liners.

Carbon nanotubes reinforced AA 7075 alloy was fabricated by powder metallurgy route. Multi-walled carbon nanotubes (MWCNTs) were synthesized by electric arc discharge method. Different mass fraction of CNTs was added to the AA 7075 and the powder mixtures were consolidated using uniaxial press. The consolidated samples were sintered at 600˚ C in inert atmosphere followed by hot compaction at 450˚ C. The electrochemical corrosion behaviour of AA 7075 and CNT reinforced AA 7075 was studied using Electrochemical Polarization Technique (ACM Gill) and Electrochemical Impedance Technique. The relative densities of the composites were measured. The phase analysis and surface morphology of the composites were done by XRD and scanning electron microscope (SEM). The corrosion behaviour of the composites and the possible mechanism for the effect of CNT in the properties have been studied in detail in this paper.

The role of metal matrix composites (MMCs) has gained huge momentum in various researches as well as in industrial applications due to their high stiffness and higher strength to weight ratio. It helps in achieving enormous weight reduction without compromising the strength of the material. In this study, a novel attempt was made to fabricate MMCs with martensitic stainless steel as matrix and titanium diboride (TiB₂) as reinforcement. The AISI 420 matrix with different weight percentages (1%, 2%, and 4%) of TiB₂ reinforcement was fabricated by vacuum induction melting technique (VIM). The aim of this study was to analyze the influence of TiB₂ particle addition on the mechanical and tribological properties of AISI 420 composites. X-ray diffraction studies revealed the presence of TiB₂ phase in the composite along with peak shifting and broadening of the steel matrix due to induced strain. Optical microscopy showed the distribution of TiB₂ particles in the matrix along with a significant amount of grain refinement of the composite due to the addition of TiB₂. Microhardness results showed that the presence of TiB₂ improved the hardness with AISI 420/4%TiB₂ composite possessing the maximum hardness. Tensile test results indicated a significant improvement in the ultimate tensile and yield strength of the composite with the addition of TiB₂. The wear tests were carried out on a pin on disc tribometer for various loads at a different sliding distance for steady sliding velocity. The dispersion of TiB₂ particle helped in achieving better wear resistance of the composites. Wear surface morphology was carried out to explore the wear mechanisms. Among the various wear mechanisms, abrasion and oxidation phenomena dominated in the composites. Taguchi optimization technique predicted that wt% of TiB₂ and applied load as influencing factors on the wear rate of the material.