Kajian Letak Saluran Masuk (Ingate) Terhadap Cacat Porositas, Kekerasan, Dan Ukuran Butir Paduan Aluminium Pada Pengecoran Menggunakan Cetakan Pasir

Abstract

Abstract : This study aims to determine the effects of ingate position to porosity defect, hardness, and grain size of aluminum alloys in casting by using sand molds. The raw material of this study is aluminum alloy. This reasearch will be assessed position of ingate in top and bottom. Porosity testing is conducted by comparing the real density to the apparent density. Grain size testing is conducted by using image analysis software with perimeter approach. And hardness testing is conducted by using microvickers hardness test in accordance with ASTM E92-82. The results showed that the average percentage of the highest porosity found in the position of the ingate in top 10.34% while in bottom just 8.16% Hardness increases as the percentage decrease in porosity defects that occur. The position of ingate in top has a hardness 94.06 HV while in bottom 102.1 HV. The average perimeter of grain size of position ingate in top 25.39 μm while in bottom 22.77 μm. The greater the percentage of porosity and the grain size, the lower hardness values of these metals.

Keywords : Sand casting, Ingate, Porosity, Hardness, Grain size, Aluminum alloy