PRODUCT CATEGORIES

Vacuum Heat Treatment Furnace

Vacuum Sintering Furnace

Vacuum Brazing Furnace

What is vacuum heat treatment

What is heat treatment?

It refers to a method of changing the internal structure of metals and alloys and changing the physical, chemical and mechanical properties of metals and alloys through solid metals at a certain heating temperature, heat preservation for a certain period of time and cooling at a certain speed. To put it simply, machining is surgery, while heat treatment is internal medicine.

What is vacuum heat treatment

Vacuum heat treatment refers to the combination of vacuum technology and heat treatment technology, and metal workpieces are heat treated in a vacuum state. Compared with heat treatment, vacuum heat treatment can improve the quality of metal workpieces. In short, vacuum heat treatment is like an upgraded version of heat treatment, or heat treatment 2.0.

Characteristics of vacuum heat treatment:

High quality: no oxidation, no decarburization, and small deformation on the surface of the parts;

Improve mechanical properties and extend service life: The obvious improvement in plasticity and toughness is due to the degassing effect of vacuum heat treatment;

Low energy consumption: The use of insulating materials with good thermal insulation performance and small heat capacity makes the furnace heat storage and heat dissipation losses very small, and the thermal efficiency is high.

Reduce pollution, no pollution: Vacuum electric heating, there is no furnace gas and no combustion exhaust gas, so there is no pollution to the atmosphere

High cost.

Benefits of vacuum heat treatment

1.Stronger protection: Vacuum heat treated workpieces will not be oxidized or decarburized, and have better gloss and quality. Moreover, in a vacuum state, no reduction reaction will occur when the metal is heat treated, so carburization will not occur.

2.Improve performance: Vacuum heat treatment can effectively improve the overall mechanical properties, degassing, and promote the purification of metal surfaces.

3.Reduce the probability of deformation: Vacuum heat treatment of workpieces can effectively reduce the probability of deformation, and the product qualification rate is greatly improved.

4.Reduce volatility: Vacuum heat treatment can be heated and vacuum quenched in a controlled atmosphere to reduce the volatility of alloy elements in the workpiece and ensure the heat treatment quality of the workpiece.

5.Higher efficiency: The vacuum heat treatment furnace has high thermal efficiency and can achieve rapid heating and cooling; it has good stability and repeatability; it has a good working environment, safe operation, no pollution, and no pollution.

Special effects and associated phenomena of vacuum heat treatment:

Surface protection;

Surface purification effect: while preventing oxidation, it will decompose oxidized substances; Degreasing effect: the oil dirt brought in during machine processing will be decomposed into oxygen, water vapor and carbon dioxide after being heated;

Degassing: The gas in the metal diffuses to the surface, the gas escapes from the metal surface, and the gas is discharged from the vacuum furnace.

Evaporation (evaporation) phenomenon of elements: Alloy elements with high vapor pressure evaporate from the surface of the workpiece, resulting in a reduction in material properties; at the same time, vacuum evaporation may occur, affecting the quality of vacuum heat treatment.

Vacuum heating oil quenching causes carburization of steel parts:

For example, for 30CrMnSiA and 30CrMnSiNi, steel A was oil quenched at a vacuum of 10×133.3Pa and a heating temperature of 900°C, and carburization was found.

The vacuum system of the vacuum heat treatment furnace must meet the following three basic requirements.

1.The vacuum heat treatment furnace can be quickly pumped to the required ultimate vacuum degree. 2. It should be possible to promptly discharge the gas continuously released from the workpiece being processed and the structural parts in the furnace, as well as the gas that penetrates into the furnace due to vacuum leakage. 3. The operation, installation, maintenance and repair should be simple, and the entire system should occupy a small area. Vacuum heat treatment is a new heat treatment technology that combines vacuum technology with heat treatment technology. The vacuum environment in which vacuum heat treatment occurs refers to an atmosphere environment below one atmospheric pressure, including low vacuum, medium vacuum, high vacuum and ultra-high vacuum. The actual vacuum heat treatment It also belongs to atmosphere controlled heat treatment. Vacuum heat treatment means that all and part of the heat treatment process are performed in a vacuum state, and the quality of heat treatment is greatly improved. Compared with conventional heat treatment, vacuum heat treatment can achieve no oxidation, no decarburization, and no carburization. It can remove phosphorus chips on the surface of the workpiece and has degreasing and degassing functions, thereby achieving a bright and purified surface.

Composition of vacuum system: The vacuum system of vacuum heat treatment furnace generally consists of vacuum pump, vacuum valve, vacuum measuring instrument, cold trap, pipeline and other parts. Vacuum degree: the degree of negative pressure in a vacuum state. Classification of vacuum: According to the degree of vacuum, it is divided into four categories: low vacuum: (10-10^-2)×133.3Pa; medium vacuum: (10^-3-10^-4)×133.3Pa; high vacuum: (10^-5-10^-7)×133.3Pa; ultra-high vacuum: 10^-8×133.3Pa.

The vacuum heat treatment process plays a vital role in the field of machinery manufacturing, providing powerful power output for building materials, aerospace, railways, petroleum, military, etc.