G.B. Veeresh Kumar

Mechanical and dry sliding wear behavior of Al7075 alloy-reinforced with SiC particles

In this article, the experimental results of the mechanical and tribological properties of Al7075–SiC composites are presented. The composites of Al7075 containing 2–6u2009wt% SiC were fabricated by liquid metallurgy route. The experimental results showed that the density of the composites increase with increased SiC contents and are in line with the values obtained by the rule of mixtures. The hardness and tensile strength of the Al7075–SiC composites are found to be increased by increased volume percentage of ceramic phase at the cost of reduced ductility. The wear properties of the composites containing SiC exhibited the superior wear-resistance properties.

Studies on properties of as-cast Al6061-WC-Gr hybrid MMCs

Aluminum (Al) alloys started replacing cast iron and bronze alloys in the manufacture of wear-resistant parts and are materials of interest owing to their low density, higher strength to weight ratio, which is an additional advantage in aerospace, marine and automotive applications. Al-metal matrix composite (MMC) materials are very much popular due to the reason that these composites possess good mechanical properties and higher wear resistance. This article is aimed to present the experimental results of microstructure, hardness, tensile, yield and compression strength, percentagage elongation, volumetric wear loss, and wear rate of Al6061-Tungsten Carbide (WC)–Graphite (Gr) reinforced hybrid MMCs. The composites were prepared using the liquid metallurgy technique, in which 0 to 4u2009wt% of WC particulates were dispersed into the matrix alloy in steps of 1u2009wt% by maintaining the Gr to 4u2009wt% constant. The experimental results indicate that the density of the hybrid-MMCs increases with increased WC content and further, agree to the values obtained through the rule of mixtures. The physical, mechanical and the tribological properties of the Al6061-WC-Gr hybrid MMCs were found to increase with increased WC content in the matrix at the cost of reduced ductility. The WC and Gr reinforcements contributed significantly in improving the wear resistance of Al6061-WC-Gr hybrid MMCs.

Fracture Toughness of Glass Epoxy Laminates Using Carbon Nano Particles and ETBN Rubber

Fiber-reinforced laminated composites have excellent mechanical properties along the fiber in-plane direction. However, they do not have very good properties in the transverse direction. The objective of this research is to deal with this problem by using graphene oxide (GO), plasma-treated multiwall carbon nanotubes, and nanodiamond extra pure powder with epoxy-terminated butadiene nitrile liquid rubber to improve the through-thickness fracture toughness of glass/epoxy unidirectional pre-preg laminates. The experimental results show that by adding carbon nanoparticles with rubber in small quantities, the mode-I interlaminar critical energy release rate can be improved by 50 to 103 %. Furthermore, it was observed that there was an increase in flexural stiffness by 15 % with the addition of nanodiamond extra pure powder to rubber. However, when GO was used, the mode-I interlaminar fracture toughness improvement was reduced as compared to other nanoparticles modified by glass/epoxy fiber laminates. The fracture surfaces were analyzed using scanning electron microscopy to understand the increase in toughness in modified glass epoxy pre-peg laminate system.

Thermal analysis on x-ray tube for exhaust process

It is great importance in the use of X-rays for medical purposes that the dose given to both the patient and the operator is carefully controlled. There are many types of the X- ray tubes used for different applications based on their capacity and power supplied. In present thesis maxi ray 165 tube is analysed for thermal exhaust processes with ±5% accuracy. Exhaust process is usually done to remove all the air particles and to degasify the insert under high vacuum at 2e-05Torr. The tube glass is made up of Pyrex material, 95%Tungsten and 5%rhenium is used as target material for which the melting point temperature is 3350°C. Various materials are used for various parts; during the operation of X- ray tube these waste gases are released due to high temperature which in turn disturbs the flow of electrons. Thus, before using the X-ray tube for practical applications it has to undergo exhaust processes. Initially we build MX 165 model to carry out thermal analysis, and then we simulate the bearing temperature profiles with FE model to match with test results with ±5%accuracy. At last implement the critical protocols required for manufacturing processes like MF Heating, E-beam, Seasoning and FT.

Artificial Neural Networks for the Prediction of Wear Properties of Al6061-TiO2 Composites

The exceptional performance of composite materials in comparison with the monolithic materials have been extensively studied by researchers. Among the metal matrix composites Aluminium matrix based composites have displayed superior mechanical properties. The aluminium 6061 alloy has been used in aeronautical and automotive components, but their resistance against the wear is poor. To enhance the wear properties, Titanium dioxide (TiO2) particulates have been used as reinforcements. In the present investigation Back propagation (BP) technique has been adopted for Artificial Neural Network [ANN] modelling. The wear experimentations were carried out on a pin-on-disc wear monitoring apparatus. For conduction of wear tests ASTM G99 was adopted. Experimental design was carried out using Taguchi L27 orthogonal array. The sliding distance, weight percentage of the reinforcement material and applied load have a substantial influence on the height damage due to wear of the Al6061 and Al6061-TiO2 filled composites. The Al6061 with 3 wt% TiO2 composite displayed an excellent wear resistance in comparison with other composites investigated. A non-linear relationship between density, applied load, weight percentage of reinforcement, sliding distance and height decrease due to wear has been established using an artificial neural network. A good agreement has been observed between experimental and ANN model predicted results.

Influence of WC Particulate Reinforcement on the Mechanical Properties and Sliding Wear of Al6061 Alloys

The research community has acknowledged the superiority of composite material properties in comparison to conventional materials. Aluminum Metal Matrix Composites (MMCs) sought over other conventional materials in the fields of automotive, sports, aerospace and marine applications due to their admirable improved properties. These materials are of much interest to the researchers from few decades. In this paper, the investigational results of the sliding and mechanical properties of Al6061–WC metal matrix composites are presented. The Al6061 composites containing 0–3 wt% WC were dispersed in the base matrix in steps of 1 and fabricated by powder metallurgy technique. The experimental results revealed that with an increase in WC content there was an increase in the density of the composites and these values are in sync with the theoretical values determined by the rule of mixtures. The tensile strength and hardness of the Al6061–WC composites are directly related to weight percentage of WC and an increase was observed with a decrease in ductility was observed.Wear properties increased, compared to as-cast Al6061 with an increase in WC content in the matrix.