Effects of Pressure on the Mechanical Properties and Microstructure of Die Cast Aluminum A380 Alloy

Kenneth N. Obiekea, Shekarau Y. Aku, Danjuma S. Yawas

Department of Mechanical Engineering, Ahmadu Bello University, Zaria, Nigeria.

DOI: 10.4236/jmmce.2014.23029                

Abstract

In this paper, the mechanical properties and microstructure of die cast aluminium A380 alloy casts produced under varying pressure was investigated experimentally and compared. The results obtained show better mechanical properties i.e. hardness, tensile strengths and impact strengths in the die cast A380 alloy sample that solidified at high pressure when pressure was regulated across five samples of the castings. The hardness of the die cast A380 samples that solidified under different applied pressures varied from 76 to 85 HRN. Also tensile strength, yield strength and elongation of the samples showed an increase with increased pressure. Also the results of SEM and metallography show that at high pressure, structural changes occurred as a fine microstructure was obtained with increase of pressure.

Keywords

A380 Alloy, Die Casting, Microstructure, Pressure

Conflicts of Interest

The authors declare no conflicts of interest.

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