1. One divides into two: different materials, equipment, and process parameters leads to different organization and quality
after heat treatment. Even if the material brand, equipment, process parameters are the same, because of the upper and lower
content of chemical composition, heat treatment temperature and heat preservation time are different, the organization and
the quality will be different after the heat treatment. Even if the upper and lower content of chemical composition, heat
treatment temperature upper and lower limit, heat preservation time upper and lower limit are the same, because of the
previous hot and cold processing technology, quality, organization are different, organization and quality can also be different
after heat treatment. Therefore, specific analysis to specific problems. That is one divides into two.
2. Two figures: Fe-C phase diagram and C curve, Fe-C phase diagram is the essential knowledge of dealing with steel,
C curve is organization transformation diagram of steel after heating cooling, these two figure is the basis of the heat
treatment foundation. Only a grasp of the two figure, insight into them is likely to deal with heat treatment and get the work
started.
3. Three processes: the heating, heat preservation and the cooling. The three process throughout all of the heat treatment
process, the stand or fall of the three process determines the quality of the final heat treatment. Understanding these three
processes thoroughly is the introduction to the heat treatment.
4. Four fires: annealing, normalizing, quenching and tempering. The four fires is one of the most conventional heat
treatment, the stand or fall of them, to some extent reflects the level of heat treatment. Someone can be a heat treatment
technician with grasping these fires well.
