Observations of mechanical and manual forging on bronze as a gamelan material

Abstract

Gamelan is a traditional musical instrument used by Hindu Balinese in religious and cultural activities. The process of making gamelan begins with the manufacture of copper alloy composition (Cu) and lead (Sn), melting, casting, forging and tone forming by grinding on the surface of the blades. The process of forging on the manufacture of bronze gamelan (CuSn) with an open casting method absolutely must be done because the casting results tend to cause the occurrence of porosity. Porosity that occurs in the bronze as a gamelan material will affect the sound produced. The research conducted is to compare the results of manual forging and mechanical means, where the observations are made on the percentage of deformation that occurs, the density, the hardness and the microstructure of the bronze material. The observations show that mechanical forging provides better mechanical properties, deformation rates, and product microstructure.