Effect of Various Sizes of TiO2 Nano-Particulate Composites on Mechanical and Tribological Properties Synthesized by Bottom Pouring Stir Casting Method
Authors: Raghu S , Nanjundaswamy H M , Harti Jayasheel I , Manjunatha B , Sreeniv M , N Sujana 
Published: November 2022

Abstract
Nanocomposites are a combination of matrix and nanoparticle reinforcement. The general idea behind adding reinforcements at the nanoscale is to create synergies between the various components, allowing for new features that meet or exceed design expectations. The properties of nanocomposites is governed by a range of variables, particularly reinforcement materials that have nanoscale dimensions, dispersal, size, shape, and orientation of the reinforcements with secondary phase matrix materials. Recent researchers has focused on Nano Metal Matrix Composites (NMMC) because of their unique properties of high strength and lightness. However, because of the high cost of raw materials and processing technology, it is difficult to mix the nanoparticles with the matrix. Therefore, the practical application of nano composites in industry will differ from other Metal Matrix Composites (MMC), has not been realized. Nano-fillers such as particles, fibers, rods, etc. are too expensive to produce, even complex roots. The nature of NMMC as well as mechanical, tribology, electrical and thermal property will be significantly different from those of MMC. NMMC is different from micro- particle and macro-particle sized MMC because the surface area to surface ratio of the nanoparticles is very high. The sorts of nano reinforcements includes Nanoparticles, Nano-flakes, Nanotubes, Nano-rods, Nano-sheets etc. Due to the higher surface area of the nanoparticles, which consecutively increases in the interface surface area of the matrix and particles. The material properties of the NMMC are significantly superior to those of the traditional MMC. Nanocomposites are materials that integrate nanoparticles into a matrix of standard materials and alloys. The addition of nanoparticles results in a significant enhancement of performance, which may include strength, durability in addition to electrical or thermal conductivity. The efficiency of nanoparticles is such that the extent of added material generally represents merely 0.5 to 15% by weight. In MMC, Aluminium Metal Matrix Composites (AMMCs) have acknowledged specific consideration over the last three eras because of high specific strength, stiffness and their excellent wear resistance. However, their application is limited since of its low wear resistance. Currently Particle-reinforced aluminium matrix composites is well-thought-out to have higher mechanical and tribological properties than conventional alloys. As such, these composites are widely finds applications in the automotive and aerospace industries. The focus is on developing aluminium NMMC at a reasonable price, with numerous hard and soft reinforcements, such as SiC, Al2O3, TiO2, B4C, Zircon, Tungsten Carbide, Graphite and mica. There are generally two types of manufacturing techniques accessible: (i) Solid phase manufacturing route comprises diffusion bonding, extrusion, drawing, hot rolling, PM route ii) Liquid phase manufacturing system comprises liquid metal infiltration, squeeze casting, compo casting, pressure casting. Bottom pouring Stir casting is generally considered to be a promising approach in various manufacturing processes that can be used for short-fiber metal matrix composites because of its simplicity, its flexibility and its ability for mass production. Nanoparticles of TiO2 in the form of fibers or particles have long been considered as high-strength materials. Nano TiO2 particle reinforced with Aluminium matrix produced by the solidification technique represent an expensive class of custom made materials for various engineering applications such as automotive parts, bushes and bearings. The use of nano-TiO2 reinforcing materials in metal matrix can exhibit outstanding properties at high temperatures. But, the lack of wettability amongst the aluminium and the reinforcing material leads to manufacturing complications and cavitation of the material at high temperatures. Much work has not been carried out for analysing the effects of various sizes of nano TiO2 Particles reinforced with Al Alloy matrix, so it is necessary to evaluate the various properties of aluminium metal matrix nano composites to know the effect of various nano sized TiO2 reinforcement on base matrix. Mechanical properties like ultimate tensile strength, yield strength, percentage elongation, creep, fatigue and hardness, are assessed by very few researchers. During working numerous components are exposed to sliding or rolling contacts. Subsequently it is crucial to study the mechanical and wear behavior of AMNCs. In the current work an effort has been made to review the effect of different nano sized TiO2 particles reinforced with LM0 Al alloy synthesised by using bottom pour stir casting technique and Microstructure, EDS, XRD, Mechanical and Tribological behaviour have been evaluated.