The following are some common serious misunderstandings of heat treatment:1. The heat treatment hardness HRC of my product can only be 60HRC. I can't accept 59 or 61HRC.
It is often encountered that the hardness value of the entrusted heat treatment product can only be at a certain value without deviation. For example, if the heat treatment hardness is required to reach 60HRC, if you reach 59HRC after heat treatment, or 61HRC, it will be regarded as an unqualified product. As everyone knows, the allowable deviation of Rockwell hardness machine is still 1HRC.2. The workpiece quenched by heat treatment is not cooled to room temperature and cannot be tempered?
Some people think that after the heat treatment has been quenched, it cannot enter the tempering process before it has cooled to room temperature. In fact, many steel grades, especially low- and medium-carbon steels, have a martensite transformation end point higher than room temperature. When they are cooled to room temperature, they are prone to cracking. After quenching, they can be transferred to the tempering process as soon as possible.3. The workpiece quenched by heat treatment must be tempered with temperature?
This approach is not advisable, and the furnace entry temperature before tempering after quenching should be determined according to the martensite transformation point of the steel. In order to prevent quenching cracking, we can not speculate arbitrarily, and adopt the method of tempering with temperature in general.4. After my product is annealed, can you heat-treat it after it has been placed for a week?
Some people think that after the heat treatment and annealing, the quenching and tempering treatment cannot be performed immediately. Said that this can increase the service life of the mold. This view is wrong.5. The product size processing has been completed, and the heat treatment is required to ensure that it is not deformed?
In order to save the cost of product processing, some people process all the dimensions before heat treatment, and then go to heat treatment, quenching and tempering. The heat treater is required to ensure that there is no deformation during the heat treatment process, or only allow the amount of deformation to be within the tolerance range of the last cold working. The process of heat treatment is essentially a stage of tissue deformation. No one can guarantee that the deformation accumulation at the microscopic level will not show up as a dimensional deformation at the macroscopic level.