Pengaruh Lapisan Karbon Terhadap Sifat Fisis Dan Mekanis Pada Solidifikasi Besi Cor Kelabu Dalam Cetakan Permanen Untuk Tapping Awal

This study aims to determine the effect of the carbon coating on the solidification of gray cast iron in a permanent mold for the initial tapping. This study uses a permanent mold cast iron ductile (FCD). The research methodology was conducted with cast iron melting in induction furnace and the poured in molds FCD coated carbon to make gray cast iron specimens were then tested the physical properties and mechanical. Test in liquid from gray cast iron using the CE Meter test equipment and then the specimens tested gray cast iron chemical composition with spectrometer then tested violence and a micro image taken from the direct contact with air and direct contact with the mold FCD. Results of the research is a chart obtained from CE Meter 1332.5°C indicates the temperature during tapping initial cast in the mold begins on the chart that reads CE Meter decreased temperature, in 1165°C liquid temperature shape is still liquid to solid temperature 1112.3°C in order to obtain a value of CEL=4,08% ; C=3,5% ; and SI=2,3% in which iron solid starts but still the red until 1060°C temperature and hardens within 180 seconds, while the chemical composition of the test results in the form of solid or solid without carbon Fe 93,47% ; C 3,50% ; Si 1,97% and coated carbon Fe 93,25% ; C 3,69% ; Si 1,94% for other elements under 1%. The test results microstructure upper direct contact with the air contained in the form lamellar graphite while the mold directly with FCD looks cementite and the results of hardness test specimens without carbon by 229,50 kg/mm² while the carbon coated by 163,05 kg/mm². Based on these data we can conclude that the permanent mold coated carbon speeds the freezing section direct contact with the mold to form clots FCD white