Study on Micro - Nano Sized Al2O3 Particles on Mechanical, Wear and Fracture Behavior of Al7075 Metal Matrix Composites

Having Low density and being Light weight with better mechanical properties, aluminum is the most significant material and is universally used in highly critical applications like navy, aerospace and particularly automotive activities. This research work is aimed to investigate the effect of micro and nano boron Al2O3 (Alumina Oxide) to aluminium (Al) on the mechanical and wear properties of the Al composites. The micro - nano composites with 1, 2, 3 and 4 % of Al2O3 particulates in Al are fabricated using stircasting processes. It was found that an increase of Al2O3 both as micro and nano particulates content resulted in an improved hardness, enhanced tensile strength and high wear resistance. However, nano Al2O3 reinforced MMCs have better hardness, improved tensile strength and higher wear resistance as compared with micro sized Al2O3 reinforced MMCs. Grain refinement of composite and nano composite materials as compared with pure Al were observed from the microscopic images. Analysis of wornout surface and tensile fracture surface were studied by SEM analysis to examine the nature of wear and tensile fracture mode of composite samples

Investigations on tensile fractography and wear characteristics of Al7075-Al2O3-SiC Hybrid Metal Matrix Composites routed through liquid metallurgical techniques

The Al2O3-SiC reinforced Al7075 Metal Matrix Composite (MMCs) is fabricated through liquid metallurgical technique. Ceramic particulates were amalgamated into aluminium alloy to achieve improved mechanical properties and wear resistance. Al-7075/Al2O3/SiC hybrid MMCs were produced by reinforcing 2%, 3%, 4% and 5% of Al2O3 and 3%, 5% and 7% of SiC particles. Microstructural analysis was carried out to evaluate the uniform dispersal of reinforcing particulates within the base matrix. The output results indicate that the mechanical properties of the hybrid MMCs enhanced by increase the wt. % of ceramic particulates. Tensile fractography results show the internal fracture structure of the tensile test specimens in which the particulates fracture and pullouts were observed. The wear characteristics of developed composites are studied using pin on disc apparatus. The high wear resistance is observed at 5% Al2O3 + 7% SiC reinforced MMCs

Machinability study on Al7075/Al2O3-SiC hybrid composites

In the present research, the effects of volume fraction of SiC+Al2O3 particles and aging temperature on the machinability of stir-casted Al7075 metal matrix composites (MMC) have been investigated. The hybrid composites were fabricated using the liquid metallurgy route. Al7075 was reinforced with different wt. % of SiC (3%, 6%, and 9%) and Al2O3 (2%, 4%, and 6%) which were used to fabricate the hybrid metal matrix composites. The samples were aged at different temperatures (140 ºC, 160 ºC, and 180 ºC) for 4 h and cooled at furnace temperature (27 ºC). The machinability of hybrid metal matrix composites was studied by carrying out L27 orthogonal array experiments. Three process parameters were selected, such as 0.2 mm/min of the depth of cut, 0.1 mm/min of feed rate, and 1500 rpm of spindle speed. The obtained results indicate that the surface roughness and machining force of MMCs increase with an increase in weight percentage of Al2O3/SiC and decrease with the increase in aging temperature. Optimum machining force and surface roughness were obtained at 2% Al2O3 + 3 % SiC and 180°C of aging temperature

A Review on Plastic Deformation in Equal Channel Angular Pressing

Because of its potential to produce ultra fine grains Equal Channel Angular Pressing (ECAP) is widely being used now a day in almost all manufacturing sector. The physical and mechanical properties have been increasingly recognized by ECAP. In all most all manufacturing processes, with the help of plastic deformation the required shape and size are obtained for example ,sometimes products its self will be deformed through rolling, extrusion, drawing etc, and by another deforming process called the metal removal through grinding, milling and cutting operation. In these processes, load is applied on the material and the processes are continued till they get the required strain or grain refinement but it is not possible in conventional deformation. But in this sever plastic deformation process (SPD), we choose the channel angle of either 60º,90º, 112.5º, 120º, 135º and so on, that depends upon the type of material and if you are using composite material than the reinforcing particle will play an important role. There are 4 types of routes or process used in (SPD) are as follows Route A, Route BC, Route BA, Route C. In this paper we will discuss about the effect of all these channel angles (few of them) about their strain rate grain refinement etc. Along with these, we will also discuss regarding the microstructures of SPD processed samples with as cast samples

EFFECT OF AGING ON MECHANICAL AND WEAR PROPERTIES OF BERYL PARTICULATE REINFORCED METAL MATRIX COMPOSITES

This paper describes the study of effect of aging on mechanical and wear properties of ‘hot rolled’ Al6061-10% wt. of beryl particulate reinforced composites produced by stir casting have been examined. The result shows that hardness and tensile strength of ‘90% hot rolled and aged’ composites were increased by 10.28% and 3.78% as compared to ‘hot rolled’ composites respectively. The ‘hot rolled and aged’ composite shows significant decrease in specific wear rate when compared to that of ‘hot rolled’ composites