Gauge Plate & Ground Flat Stock

Heat the O1 ground flat stock component slowly and if possible pre heat at 300-500°C before increasing to the hardening temperature of 780-820°C. Pre heating is highly recommended for complex sections. Soak the component thoroughly allowing thirty minutes per 25mm of ruling section before quenching. Light section tools should be quenched in oil from the lower end of the hardening temperature range. Tempering the heat treated tool is always necessary after hardening.

Martempering of O1 ground flat stock is an alternative hardening process which may be used when suitable salt bath equipment is available. With this method internal strain, distortion and risk of quench cracking are reduced to a minimum.

Pre heat the gauge plate tool at 360°C then raise to 800°C for sections 3mm thick or less, or to 820°C for sections over 3mm thick. Soak the component according to section then quench into molten salt, held at 210°C. Allow sufficient time for the centre of the tool to reach bath temperature, withdraw and cool in the air. Tempering of the tool will then be necessary.

Hardening the O1 ground flat stock component from a neutral salt bath, will reduce the possibility of scaling or decarburisation. Heat the component to 830-850°C and after equalisation quench in oil.

Tempering is recommended between 100-350°C. Soak the tool well at the selected temperature and soak for at least one hour per 25mm of total thickness.