Operation handles produced from C45 steel showed many fine cracks at the flame hardened noses. The cracks ran from the corners of indentations caused by the tool during alignment. Metallographic investigation showed the nose was overheated during flame hardening. It was concluded that the numerous hardening cracks were caused by abrupt quenching from over-heating temperature and by local stress concentrations due to indentations of the tool caused during alignment.
Egon Kauczor, Cracks in Flame Hardened Operation Handles, ASM Failure Analysis Case Histories: Processing Errors and Defects, ASM International, 2019, https://doi.org/10.31399/asm.fach.process.c9001212
Download citation file: