Vacuum heat treatment process flow

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Vacuum heat treatment process:

The development of the vacuum heat treatment process of the mold heat treatment is accompanied by the development of the machinery manufacturing industry and development, machinery manufacturing and put forward higher requirements for heat treatment, mold heat treatment is the highest technical content of the heat treatment department.

As we all know, the mold heat treatment is to display the potential of the mold material, the use of the improvement of the mold function. The function of the mold must be satisfied with: high strength, (including high temperature strength, cold and hot fatigue resistance) high hardness (wear resistance) and high toughness, and also requires a good mechanical processing, (including good polishing) weldability and corrosion resistance and so on.

The biggest impact on the life of the mold is mold design (including accurate selection of materials) mold materials, mold heat treatment, mold use and maintenance. If the design of the mold is fair, the material is high grade, so the stand or fall of heat treatment decided the service life of the mold directly.

At present, both at home and abroad are trying to use more advanced heat treatment methods to improve the function of the mold to extend the service life of the mold. The vacuum heat treatment is one of the ways to improve the predecessor in the mold heat treatment. So from the mold heat treatment, heat treatment processing equipment, heat treatment technology, production process control is particularly important.

And the improvement of the predecessor of the equipment is to ensure the realization of the conditions to improve the predecessor. Vacuum high pressure gas quenching furnace is the most ideal equipment to realize vacuum heat treatment.

Vacuum furnace has the effect of non-decarbonization and non-oxidation, with average temperature, controllable heating and cooling rate, and different technological processes can be realized. Vacuum furnace is internationally recognized “green heat treatment” because it has no pollution.

Now there are 2-20bar vacuum high-pressure gas quenching furnaces in the world, which can fully meet the requirements of vacuum heat treatment of molds.

In the process of mould heat treatment, the technological parameters adopted have a crucial impact on the mould function: it includes heating temperature, heating speed, holding time, cooling mode, cooling speed and so on. Accurate heat treatment process parameters can ensure the mold to obtain the best function, otherwise, will produce adverse or even severe consequences.

The practice shows that the accurate heat treatment technology can obtain the fine structure, the fine structure shape can guarantee the fine mechanical function. The proper process method can effectively control the deformation and cracking of the mold during heat treatment. It is found from practice that the difference between the surface temperature and the core temperature (the unevenness of heating and cooling) is the main factor that causes the mold deformation during the heating and cooling process. The vacuum furnace has the ability to control the heating and cooling rates.

Different process methods can make the mold to meet the different premise of use and different functional requirements.

From the service life of the mold, to meet the requirements of hardness is only a mold technical requirements, it is not easy to measure some functional requirements, such as strength and toughness, and so on.

Mold quality is not entirely to investigate with hardness index, it can not use the ultimate hardness measurement method to repair the mould service life, as a special heat treatment process (i.e., special process), it can only through the process validation, functional experiment, confirm the reasonable process parameters, and strictly implement the process parameters of the confirmed process (process control) to ensure the reliability of the product quality and not random.

A large number of data show that the cold stamping die processed by vacuum heat treatment has a small deformation, and the phenomenon of linear cutting cracking and grinding is rare. The die-casting die adopts the advanced technology to reduce the cracking of die and the phenomenon of sticking die in use to some extent.

In a word, the vacuum high-pressure gas quenching process has the advantage of free control of heating and cooling speed, and different process parameters can be programmed to obtain the expected microstructure and function.

After the vacuum heat treatment, the distortion is small, the quality is high, and the process itself is flexible and pollution-free. Therefore, vacuum heat treatment is not only a necessary means for the heat treatment of some special alloys, but also has been applied in the heat treatment of general engineering steel, especially for tools, molds and precision couplings.

Main business scope:

1. Vacuum heat treatment and conventional heat treatment of mold materials such as D2 SKD11 xw-5 SKD61 H13 8407 gsw-2379 gsw-2510 K100 K100 K460 P20 718;

2. Gas nitriding, liquid nitriding and QPQ treatment of various plastic molds 420 718 and other materials;

3, stainless steel SUS302 SUS304 SUS631, stainless steel 420J1J2 and other materials bright quenching, bright annealing, solid solution treatment;

4. Solid solution and aging treatment of aluminum alloy 6061, beryllium copper QBe2 QBe1.9, etc.