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• What does the heat treatment of Q690 Steel include?
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What does the heat treatment of Q690 Steel include?

In order to obtain good mechanical properties, many high-strength steels use a combination of multiple heat treatment methods. For Q690 steel, the suitable heat treatment methods include normalizing, quenching and tempering (including medium temperature tempering and high temperature tempering).

As far as normalizing is concerned, it is necessary to heat Q690 steel to above 860°C, then keep it warm for a specified time, and then cool Q690 steel by air cooling.

The quenching treatment of Q690 steel is usually heated to above 860 ° C, and after a period of time, the Q690 steel is cooled to room temperature with quenching oil or brine containing 10% NaCl at room temperature.

Generally, after quenching, Q690 steel needs to heat the material again and keep it warm for a period of time before air cooling, so as to reduce the internal stress and brittleness of Q690 steel due to quenching, that is, tempering treatment.

This article briefly introduces the three heat treatment processes of Q690 steel. BBN is committed to professionally manufacturing high-quality steel. If you have any needs, please feel free to contact us.