Vacuum Heat Treatment of Tools and Molds

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The vacuum heat treatment of the mold refers to the process of placing the mold parts in the vacuum heat treatment equipment for heating, heat preservation and cooling. It is one of the current advanced mold heat treatment technologies. Vacuum heat treatment is especially suitable for molds with high precision, stable size and performance. Mold vacuum heat treatment technologies include: vacuum quenching, vacuum tempering, vacuum carburizing, vacuum nitriding, etc.

Advantages of vacuum heat treatment:

With the increasing requirements of mold quality, it is difficult for general heat treatment to meet the technical requirements. After vacuum heat treatment, the surface of the mold is not oxidized or decarburized, the quenching distortion is small, the surface hardness is uniform, the performance is improved, and the service life of the mold is generally increased. Generally, it can be increased by more than 30%. In addition, vacuum heat treatment can reduce the machining allowance (grinding or polishing) by 1/3~1/2, thereby improving production efficiency and reducing mold manufacturing costs.

Process application:

1. Vacuum oil quenching: suitable for alloy tool steel, high carbon and high chromium alloy steel, high-speed tool steel and other mold steel, using special vacuum oil quenching. Vacuum oil quenching is especially suitable for molds that require high strength and toughness.

2. Vacuum air quenching: reduce mold distortion, shorten the process cycle, and achieve clean heat treatment production. Air-cooled quenching is increasingly used internationally. According to the different gas quenching pressure, it can be roughly divided into the following three categories:

(1) 0.2MPa vacuum air quenching: that is, low pressure vacuum air quenching, the maximum cooling pressure of nitrogen quenching is 0.2MPa, and the purity of nitrogen is above 99.95% (volume fraction), which is generally used for high-speed tool steel and Hot and cold working die steel.

(2) 0.6MPa high-pressure gas quenching: its nitrogen quenching pressure is 0.6MPa, which is generally used for the quenching of high-speed tool steel, high-carbon and high-chromium alloy steel, and some alloy tool steel to make molds.

(3) Ultra-high pressure gas quenching above 1MPa: generally used for all high-speed tool steel, hot work die steel, cold work die steel, Cr13 steel and some oil quenched alloy steel. It is also suitable for quenching of large and medium-sized molds.

3. Vacuum water quenching: used for quenching and cooling of non-ferrous metals, heat-resistant alloys, titanium alloys and carbon steel.

4. Vacuum nitrate quenching: The use of nitrate for mold classification or isothermal quenching can reduce mold distortion, avoid cracking, and prevent decarburization of high-strength structural steel. The total cooling capacity of a static nitrate bath is equivalent to that of oil. Stirring can improve the cooling capacity of the salt bath, and the temperature is generally controlled at 160~280℃.

5. Vacuum annealing: Die steel vacuum annealing is easy to achieve no oxidation and no decarburization heat treatment, which is conducive to improving the surface quality and production efficiency of the mold, shortening the process cycle, the surface of the mold can be bright, and the microstructure is uniform.

6. Vacuum carburizing: Vacuum carburizing is heating the mold to austenitizing state in a vacuum furnace, carburizing in a carburizing atmosphere, and then diffusing and quenching. Because the mold is heated in a vacuum state, the surface of the mold is very smooth, which is suitable for carburizing treatment of molds with high surface quality requirements.

Although the vacuum heat treatment of molds has various benefits, it is necessary to select a high-quality vacuum furnace that meets the needs of the process in order to produce a sufficiently good product.

SIMUWU provides a series of products for vacuum heat treatment including vacuum air quenching furnace, vacuum oil quenching furnace and vacuum carburizing furnace. The main models include RVGQ vacuum air quenching furnace series, VOGQ vacuum oil quenching furnace series, RVA vacuum annealing furnace series And RVC vacuum carburizing furnace series, etc., with its more than ten years of accumulated production and sales experience, to create easy-to-use and reliable products for manufacturers.

In addition to the standard models, it also provides a series of customized services. The furnace body size and components can be selected according to the process requirements, and a complete service process from installation to after-sales is provided. It is an excellent choice for various heat treatment plants.