ENHANCEMENT OF CARBIDE-FREE HADFIELD STEEL HARDNESS FOR FROGNOSE RAILWAY APPLICATIONS

• Main Author: Viegho Anthory, Mohamad
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/82892
• Institution: Institut Teknologi Bandung

Hadfield steel, an austenitic manganese steel with 1,2% C and 12% Mn, is renowned for its exceptional toughness and wear resistance, making it suitable for high-impact applications such as frognose railway components using solution treatment and shot peening techniques. According to the technical requirements for railway tracks that comply with EN 15689, the microstructure of Hadfield steel must be free of carbide. This research involves the preparation of Hadfield steel specimens, followed by solution treatment at 1150°C to dissolve carbides, and then shot peening with varying times and intensities to induce strain hardening. The characterizations conducted include hardness testing, surface contour analysis, surface roughness measurement, and metallography. The research results show a significant increase in surface hardness after shot peening, with all treated specimens meeting the minimum hardness requirement of 370 HV (37-38 HRC) in accordance with the Minister of Transportation of the Republic of Indonesia Regulation No. 60/2012 and the technical standards of EN 15689. Microstructural analysis revealed the formation of twinning mechanisms contributing to the hardness increase. This study concludes that the combination of solution treatment and shot peening effectively optimizes the mechanical properties of Hadfield steel, making it a viable material for frognose applications.