Synthesis and Characterization of Al7075/SiC Composite by Stir Casting

Abstract

In recent years, stringent requirements of material quality in automotive and aerospace industries have necessitated the development of lightweight aluminum alloys. In this context, it is known that the metal–matrix composites offer a spectrum of advantages that are important for their selection and use as structural materials. A few such advantages include the combination of high strength, high elastic modulus, high toughness and impact resistance, low sensitivity-to changes in temperature or thermal shock, high surface durability, low sensitivity to surface flaws, high electrical and thermal conductivity, minimum exposure to the potential problem of moisture absorption resulting in environmental degradation, and improved fabricability with conventional metal working equipment Metal matrix composites (MMC) are generally produced either by liquid metallurgy or powder metallurgy techniques. Stir casting is one of the most inexpensive tools for the production of particulate metal matrix composites . It is simplest and most commercially used technique for casting MMCs. This involves incorporation of ceramic particulate into liquid aluminum alloy in molten state and allowing the mixture to solidify. Here, the crucial thing is to create good wetability between the particulate reinforcement and the liquid aluminum alloy. In this proposed work , composites of Al7075 with SiC were fabricated using Stir casting method by using both upward and downward pouring methodology .The main objective of this research work are to achieve uniform distribution of SiC particles in the aluminum alloy matrix , characterization and analysis of mechanical properties of composites formed . Experiments were carried out with different stirring speeds and specimen of different %wt of SiC were cast . Microstructure , Tensile strength and hardness values were found by conducting the corresponding tests and results were analyzed and compared . Keywords - MMCs , Stir casting , Wire cut EDM , SiC reinforced metal matrix composites

Enhancing the fatigue strength of stir-casted Al7075-SiC composites through heat treatment and shot peening

“…One of the major factors that determine the properties of the resulting material is the uniform distribution of reinforcement within the matrix. This can be confirmed through various microstructural studies [20,21]. Researchers vary one or more parameters, such as stirring speed, time of metal melt, pre-heating temperature of reinforcement and die, processing temperature, time of holding the metal melt, and method of casting, in order to achieve maximum properties from the resulting material.…”

Effect of Shot Peening and Heat Treatment on Fatigue Strength and Microstructure of Stir Casted Al7075-SiC Composites

“…MMCs are fabricated by powder or liquid metallurgy methods. Stir casting is an economic, simple and commercially available method for producing metal matrix composites [5]. Mechanical, wear behaviour and microstructural analysis are usually carried out on composites made by this technique [6].…”

Machinability Study on AA6061/2 SiC / Graphite Hybrid Nanocomposites Fabricated through Ultrasonic Assisted Stir Casting

“…Vinoth et al [4] synthesized an Al 7075 / SiC composite via stir casting. Microstructure analysis conveyed that reinforcement particles were distributed uniformly since stir casting was chosen as the method of fabrication.…”