Quenching medium selection principles for steel plant

Quenching medium selection principles for steel plant

Quenching was Ms point temperature of the steel above the appropriate speed to slow cold cold Ms point or less, achieve superior organizational performance. Need to quench quenching medium, a common cooling medium is quenching oil, water-soluble quenching agent, water and saline and alkaline, but no matter what kind of media should follow the principle of choice:

The temperature, the lower the carbon content of steel due to possible precipitation of eutectoid ferrite and austenite its supercooled pearlite transformation most likely to occur at high temperature, the martensite start (Ms) and higher order so that such artifacts fully hardened steel, quenching medium used should have a shorter vapor film stage and appear highest cooling rate of temperature should be higher. Of high carbon content steel, film vapor phase quenching medium may be longer, the highest temperature of cooling rate appear correspondingly lower.

When the workpiece relatively large and thick as a hardened layer depth sufficient thickness, quenching medium used should have a fast low. Temperature and cooling rate. In contrast, the thin workpiece hours, you can use low-temperature cooling rate smaller quenching medium.