The Effect of Element (Sr, Ti, B, and Mg) Modification on Microstructure to Increase Micro-Hardness of A356 Aluminum Alloy

Afghany Mostavan; Asep Ridwan; Arif Basuki; Husaini Ardy

Afghany Mostavan Doctoral Program of Materials Science and Engineering, Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40132, Jawa Barat, Indonesia
Asep Ridwan Department of Materials Science and Engineering, Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40132, Jawa Barat, Indonesia
Arif Basuki Department of Materials Science and Engineering, Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40132, Jawa Barat, Indonesia
Husaini Ardy Department of Materials Science and Engineering, Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung, 40132, Jawa Barat, Indonesia

Keywords: A356 alloy, microstructure modification, micro hardness

Abstract

It is known that Sr, Ti, B, and Mg can modify the microstructure of the A356 aluminum alloy, and the heat treatment process causes spheroidization of eutectic silicon. This experiment presents the effect of modifier elements and heat treatment on microstructure and microhardness. The A356 aluminum alloy is modified with a combination of elements containing Sr, Ti, B, and Mg. The microstructure analysis of the modified A356 aluminum alloy revealed that the size distribution of the α-phase and eutectic silicon particles that form spheroid Si particles varies depending on the combination composition. Comparisons between unmodified and modified alloys show that the aspect ratios of the α phase and the eutectic silicon particles are different. The modified A356 aluminum alloy's microhardness can be improved. This could be related to the aspect ratio of the α phase and eutectic silicon phases, spheroidization of fine eutectic silicon, and precipitation hardening.

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