how hardened and tempered steel strip operate

How hardened and tempered steel strip operates

 

There are four steps in the process of hardneing and tempering. When steel strip has been well operated in cold rolling process, it goes to hardeneding process, which is heated gradually until it reaches a high temperature in hardening facility. When strip steel reaches a temperature, it turn red. At second step, strip steel are  put directly into cool water. At this point, the steel is very hard and brittle. After these two steps, the hardening process has ben done and strip moves to 3rd steps of tempering process. Steel are reheated to receive the most intense until steel tures blue color which means the tempering has occurred and heat source is cut off. The 4th step is to let strip steel after hardening and tempering process,cooling slowly on its own. Strip steel, after 4 steps of hardened and tempered process, has been improved in toughness and ductility.