The hardness of SUS630 is directly related to its heat treatment state, ranging from 28–32 HRB (solution-treated) to 30–45 HRC (aged), with lower aging temperatures producing higher hardness.
Hardness in different states:
Solution-treated: Heated to 1040–1060°C and rapidly cooled, hardness is 28–32 HRB. The material has good plasticity and is suitable for machining and stamping.
Aged state (typical process: hold 4 hours + air cooling):
480°C aging: 39–45 HRC, suitable for applications requiring high strength and hardness.
550°C aging: 36–42 HRC, balances strength and toughness, widely used industrially.
590°C aging: 33–38 HRC, better toughness with medium strength.
620°C aging: 30–32 HRC, good toughness, suitable for low-temperature or impact-resistant applications.