The gas quenching furnace is heat treated in die casting mould
The workpiece has no oxidation, no decarburization and degreasing in the vacuum heating.
The behavior is increasingly restricted or prohibited. Because the vacuum can be degassed (especially the harmful gas hydrogen in the mould), the surface is clean.
Heat treatment is free of pollution, so it has developed very rapidly in our country in recent years. The surface performance is improved obviously, and the wear resistance can be improved.
The first 6 bar real air quenching furnace is more common, but the large die is in 6 fatigue strength.
In bar real air quenching furnace, the cooling rate is not ideal, and the heating speed is controllable in the vacuum heating of the mold, and the temperature difference of the mold section is small.
The impact toughness and service life of the device have a great impact. In order to accelerate the cooling caused by thermal stress, the deformation is 70% less than that of salt bath quenching.
It is very effective to improve the air cooling pressure of vacuum furnace. When quenching, the cooling gas can enter the workpiece within 360 degrees.
10 bar real air quenching furnace has become a hot spot. Because of the time line jet cooling, the cooling is uniform, the workpiece will not appear soft spot, quenching.
In a short time, 6 bar real air quenching furnace and 10 bar true air quenching furnace have uniform hardness.
The comparison test has not been able to be filled in, and the collection of technical data is also owed.
Lack of. Therefore, this paper only serves as a vacuum high-pressure gas quenching furnace for 10 bar real air quenching furnace in pressure casting.
A superficial discussion of the application of mold heat treatment, the life of the die casting die depends on a variety of factors, such as the chemistry of the material.
Pray for your colleagues in the industry. Composition, smelting process, metallographic structure, mold design and machining,
Mold specification, mold use and maintenance, and forging process, hot spot.
1. Technology and technology of mass transfer.
There are two main failure modes for preventing the oxidation and decarburization of the surface and the die-casting die.
Shape and crack, the traditional process is to use deoxygenated barium chloride high temperature salt. The typical crack of thermal cracking is reticular distribution of tortoises.
Bath or protective atmosphere electric furnace heating, or box protection after the ordinary striated crack, also in the high temperature and stress concentration areas.
It is heated in a box-type electric furnace. Small crack.
We used to use high temperature salt bath to heat, there are many problems: severe cracking. Severe cracking occurs when the mold is used.
The heat treatment has a large labor intensity and harsh working environment. It is often found in the surface of the mold surface that the crack source is the most.
The exhaust gas, waste furnace slag, salt and old electric furnace caused pollution to the environment, and then the brittle fracture suddenly cracked, causing the die to be scrapped.
Salt bath treatment has been limited. ? Practical experience shows that the length of die depends on the material.
The surface of the workpiece after the quenching of salt bath is easy to be corroded by the salt bath. Even if the performance is good or bad, the mould material of the good and good should have the ability to delay the crack.
After the workpiece is cleaned and grinding, it is easy to rust in use, resulting in the ability of life and expansion. The key to improve die life is:
The working life of the workpiece is reduced. The ability of the material to resist plastic deformation at high temperature, namely, high temperature flexion.
Due to the fast heating speed, the temperature difference of the workpiece section temperature and the tempering ability of the materials under high temperature, the hardness is not easy to decrease.
Large, increased by thermal stress. The thermal conductivity is good and the thermal expansion is low.
In the quenching process of salt bath, the cooling is not uniform, easy to appear soft spots, and the ability to absorb plastic deformation is high, which is the ductility and impact.
The hardness is not uniform and the service life is decreased. Good toughness and fracture toughness.
The above performance of die material mainly depends on the chemical composition of steel.
2 vacuum heat treatment and metallographic structure, and the smelting process is to obtain the material quality performance.
Vacuum heat treatment has the following advantages: key. Although the cause of the die cracking is the use of the die in the process.
High efficiency, low energy consumption, no pollution, low labor intensity, thermal load and mechanical load of products, but the toughness of mold materials is poor, often.