Pengaruh Perbedaan Ukuran Diameter 5mm, 7,5mm, 10mm Saluran Masuk (In-Gate) Terhadap Hasil Coran Aluminium (Al) pada Produk Pipa dengan Cetakan Pasir Merah

This study aims to determine the effect of different inlet size on chemical composition, porosity defects, micro-photos and hardness. The raw material of this research is used aluminum or rubbing from various components which are repainted. This study will examine the size of the inlet 5 mm, 7.5 mm, 10 mm. Tests carried out include chemical composition tests, porosity observations, micro-photo tests with Metallographic Microscopes, and brinell hardness tests (ASTM E-10 standard. The results showed that the results of the chemical composition were found to be found in the chemical elements (Al) 81,86%, (Si) 9,84%. So that from the elements present this material includes aluminum alloy silicon metal (Al-Si). The highest hardness price is in the in-gate 10 mm size of 98.68 BHN, while in-gate 7.5 mm is 84.46 BHN, and in-gate 5 mm is 73.07 BHN, it occurs because the porosity defect causes violence reduced metal