EFFECT OF MAGNESIUM ENHANCEMENT ON MECHANICAL PROPERTY AND WEAR BEHAVIOUR OF LM6 ALUMINUM ALLOY
For last several decades aluminium and aluminium alloys are widely used in automotive industries because for their favourable properties like low density (about 2700 Kg/m 3 ), good malleability, high formability, high corrosion resistance and high electrical and thermal conductivity. High machinability and workability of aluminium alloys are prone to porosity due to gases dissolved during melting processes. However, in the engineering application pure aluminium and its alloys still have some problems such as relatively low strength, unstable mechanical properties and low wear resistance. The microstructure can be modified and mechanical properties, wear resistance can be improved by alloying, cold working and heat treatment. In this regards, the present paper reports the influences of enhancement of magnesium contents on the mechanical properties and wear behavior of LM 6 aluminum alloy. Index Terms: LM 6 Aluminum alloy, wear rate 1. Introduction: Aluminium and aluminium alloy are gaining huge industrial significance because of their outstanding combination of mechanical, physical and tribological properties over the base alloys. These properties include high specific strength, high wear and seizure resistance, high stiffness, better elevated temperature strength, controlled thermal expansion coefficient and improved damping capacity (1). These properties obtained through addition of alloying elements, cold working and heat treatment. Alloying elements are selected based on their effects and suitability. For the purpose of understanding their effects and importance, alloying elements for majority of alloys are best classified as major and minor elements, microstructure modifiers or impurities, however the impurity elements in some alloys might be major elements in others (2). LM6 is one of the most important Aluminium alloy falls under Aluminium - Silicon alloying system in which aluminium is the predominant metal and high levels of silicon (4% to 13%) are added that contributes to give good casting characteristics and increases fluidity, by which we can produce castings of thick as well as thin sections according to the required design. Other typical alloying elements are Copper, Magnesium, Manganese, Silicon, Zinc, Iron, Nickel, Lead and Tin.
Effect of Magnesium on Wear Characteristics of Silicon Carbide and Alumina Reinforced Aluminum-Metal Matrix Composites
Magnesium (Mg) plays an important role in improving interfacial bond strength between reinforcing particles and aluminum (Al) matrix in aluminum-metal matrix composites (Al-MMC). Strong interfacial bond affects mechanical and wear properties of Al-MMC. The purpose of this work is to investigate the effect of Mg on wear characteristics of silicon carbide (SiC) and alumina (Al 2O3) reinforced Al- MMC. Al-MMC reinforced with varying wt. % of SiC and Al2O3 were prepared using stir casting fabrication technique. Hardness and wear characteristics of prepared composites were evaluated. Microstructural observation revealed random dispersion of reinforcing particles in Al matrix. Hardness test results indicated that hardness of both unreinforced Al and Al-MMC increased after Mg addition. Heat treatment increased the hardness of Al-MMC further. Pin-on-disc wear test results showed that Mg addition increased wear resistance of Al-MMC. Heat treated Al-MMC showed better wear resistance compared to as cast Al-MMC.
The Application of Using Bezier Curve to Design Turbine Blade
The blade of the turbine is analyzed,the principle and characteristics of the Bezier curve are elaborated,the paper presents a method of using Bezier curve to design turbine blade.It was proved that it's a good and simple way to design turbine blade.Through this way,you can build mathematics model easily.It's certainly had some superiority.