Can't I accept the heat treatment hardness of my product only 60HRC, 59 or 61HRC?
Frequently, the hardness value of entrusted heat treatment products can only be on a certain value, and there can be no deviation! For example, if the heat treatment hardness is 60HRC, 59HRC after heat treatment, or 61HRC will be regarded as an unqualified product. Unexpectedly, the allowable deviation of the Rockwell hardness machine is still 1HRC. If you explain heat treatment to him, he will put on a God's face: Do you want to make my heat treatment product? Market competition! The heat treatment manufacturer has to stiffen his scalp to undertake it. As for the heat treatment manufacturer, how to do it? Peers can definitely guess!
It's really "how bold people are and how productive the land is."
2. The quenched workpiece is not cold to room temperature and cannot be tempered?
Some people think that after quenching, they cannot enter the tempering process before it cools to room temperature. In fact, the endpoint of many steel, especially low- and medium-carbon steel, is mostly higher than the room temperature. When it is cold to room temperature, it is easy to crack. After quenching, it can be transferred to the tempering process as soon as possible.
3. Must the quenched workpiece be tempered with temperature?
This method is not advisable. The furnace temperature before tempering after quenching should be determined according to the martensite transformation point of steel! In order to prevent quenching cracking, it cannot be speculated. In general, the method of temperature tempering is adopted!
4. After my product is annealed, it will take a week before you can heat treat the quenching?
Some bosses claim to have the secret to improve the service life of molds! What is his secret? After all, it is required that the heat treatmentr cannot be quenched and tempered immediately after annealing. The mold must be placed at room temperature for a week between annealing and quenching! Say yes: Release the annealing stress! I don't know which expert can answer this truth?!
The world is really amazing!
5. The product size processing has been completed, and heat treatment is required to ensure that it will not deform?
In order to save product processing costs, some people finish processing all sizes before heat treatment, and then quench and temper at heat treatment. The heat treater is required to ensure that it does not deform during the heat treatment process, or only allow the deformation amount to be within the tolerance band value of the last cold processing! The process of heat treatment is essentially a stage of tissue deformation. Who dares to ensure that it does not appear at the macro level to become dimensional deformation?
In order to save his own expenses and pass on the problem to the heat handlers, are these people "smart"?!
6. Are heat-treated products not hard?
Many enterprises entrusted products for external processing have learned to require purchase inspection. Since the leader put forward this request, the guys took it seriously. They also bought a Roche hardness tester, put it in the factory, and began to inspect the heat-treated products. These are reproachable, but they always fail to pass the inspection of heat treatment products! This is too busy with the heat treatment company. How come? It is clear that he has passed the inspection and left the factory. Why is it not qualified in the hands of the user? The company can't understand it from top to bottom.
The heat treatment company takes it seriously and urgently sends personnel to deal with this matter! I really don't know if I don't look at it. I'm shocked when I see it! It turns out that they do not remove the decarbonization layer of heat-treated products (the processing margin is enough to ensure that there will be no residual decarbonization layer after processing), so they directly hit the HRC hardness on the surface of the workpiece! How can there be high hardness? My god! Who on earth distrusts whom?
