Heat the steel slowly to 650-700°C and thoroughly soak. Continue heating the steel to the final hardening temperature of 870-930°C and allow the component to be heated through. Quench in oil. Temper the spring steel immediately after quenching whilst tools are still hand warm. Through Hardening for Medium Carbon & Spring Steel PartsAustempering for Spring Steel Parts like Circlips,Washer, Ground Disc,etc…..