Case of Unhomogeneity of Wearing and Local Melting on Train's Brake Block

• Main Author: JOKO BUDIMAN (NIM 13102033), MUHAMMAD
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/10983
• Institution: Institut Teknologi Bandung

Unhomogeneity of wearing and local melting were occur on braking surface of train's brake block. Visual examinations on its braking surface showed some mount profiles a long it's surface, initial estimation said that it's surface has hard points which the hardness of that point harder than wheel hardness. On the brake block case of local melting was found the melt material which had solid, the brake block melt because it's melting point lower than normal condition, initial estimation said that the brake block has equivalent carbon percent close to eutectic point. Some testing on the brake block applied for this research. From metallography testing, we can observe the micro structures on the failure sections. Spectroscopy used to find the chemical composition in the brake block which out of composition range of the specification, base on spectroscopy result also we can calculate the equivalent carbon percent. Hardness Brinell testing used to know the variant of the brake block surface hardness. Data from all testing and visual examination will used to find the failure causes. From the research, on the unhomogeneity brake block was found Fe3C at the braking surface, that caused by very low percent of silicon, the other reason is the fasten cooling rate. Percent of carbon content which more than the maximum percent from spesification caused by equivalent carbon percent too close to eutectic point. Ferro-silicon have to adding in liquid metal. Cast iron ex-machine part need to adding in liquid metal to decrease carbon content.