Abstrak
Metal matrikkomposit (MMC) adalah material rekayasa, yang dibentukolehkombinasduaataulebih material tidaksejenisuntukmemperbaikisifatmekanisbahanmatriknya. Penelitianinibetujuanuntukmengetahuisifatmekanikkompositdenganpenguat SiO2terhadapvariasifraksimassa.
Penelitianinibertujuanuntukmengetahuipengaruhpenambahanfraksimassapenguatterhadapnilaikekerasandandensitasnya. Fabrikasi yang digunakandalampenelitianiniadalahdenganmetodestir casting, denganputaranpengadukan 800rpm, temperaturpengadukan 650oC dantemperaturpenuangan750oC. Pengujiandilakukandilaboratoriummenggunakanpengujianspesimen yang dibuatdenganpenambahanpartikelsilika (SiO2) denganvariasifraksimassa 0, 3, 6 dan 9% terhadapberataluminium. Proses pengujiankekerasanbrinellmenggunakanstandar ASTM-E10 menghasilkan data kekerasanbrinell (BHN).
BerdasarkanhasilujiBrinellterjadikenaikanseiringdenganpenambahanpenguat (SiO2), persentasepartikel 6% memilikinilaikekerasan yang tertinggiyaitu 92,37 BHN. Sedangkannilaidensitas yang terbaikdiperolehpadasaatpersentasepenguat 9%, halinidikarenakanmassajenispenguat yang lebihkecildaripadamatriknya.
Kata kunci: stir casting, SiO2, kekerasanbrinell, densitas
Abstract
Metal matrix composites (MMCs) are an engineering materials, it is formed by the combination of two or more dis-similar materials to obtain enhanced properties. This study aims to determine the mechanical properties of composites with SiO2reinforcement with variations in mass fraction.
This study aimed to determine the effect of adding mass fraction reinforcement against value of hardness and its density. Fabrication used in this research was the stir casting method, with stirring speed is 800rpm, stirring temperature is 650oC and pouring temperature is 750oC. Tests carried out in the laboratory used test specimens created with the addition of particles of silica (SiO2) with a variation of the mass fractions is 0, 3, 6 and 9% to the weight of aluminum. Brinell hardness testing process using the standard ASTM-E10 generate data Brinell hardness (BHN).
Based on the brinell test results, an increase in line with the addition reinforcement (SiO2), the percentage of particles 6% has the highest hardness value which is 92.37 BHN. While the density values are best obtained when the percentage of the reinforcement 9%, this is because the density of the reinforcement is smaller than in its matrix.
Keywords: stir casting, SiO2, brinell hardness, density