Penerapan Sistem Vakum HPDC Manual untuk Peningkatan Kualitas Produk IKM Pengecoran Aluminium ADC12

Abstract

The motorcycle industry in Indonesia is remarkable improvement, It is a great opportunity for
the aluminum casting industry to be able to supply the components of the motorcycle. IKM of foundries
have not been able to meet the technical requirements, so IKM has not dared to take part in this
opportunity. The purpose of this reaserch was to examine the effect of vacuum pressure on porosity, and
mechanical properties on manual high pressure die casting results. The specific objective of this research
is to enable IKM to improve the quality of castings, especially in reducing porosity and improving
mechanical properties by converting from sand molds (which have been used) to casting with metal
molds (high pressure systems) plus a vacuum system. The method of this research is: the selection of
ADC12 casting materials, the manufacture of precise casting machine, the making of vacuum metal
molding machine, specimen-making casting, porosity testing, mechanical properties testing (hardness).
Followed by data retrieval and data analysis. The variables of this research are fixed variable that is casting temperature 700 ^oC, and depend variable are that is the speed of injection casting and vacuum pressure that is: -250mbar, -350mbar, and -400 mbar. The average hardness of castings found with manual vacuum high pressure die casting system is 57.33 HRB, and the porosity level is 0.2015%. Thus there is a significant increase in mechanical strength and a significant decrease in porosity when compared to casting the vacuum gravity die casting system resulting in a porosity of 0.2097% and hardness of 52.45 HRB.