CN105648393A - Surface carburizing process for mold - Google Patents

Abstract

The invention discloses a surface carburizing process for a mold; 12Cr2Ni4A is adopted in material. The surface carburizing process for the mold is characterized by adopting the following steps: (1) a preparation stage; (2) a carburizing stage; and (3) a diffusing stage. The surface carburizing process for the mold, disclosed by the invention, is simple, and is capable of increasing surface mechanical property and abrasion resistance, shortening carburizing time and increasing service performance and a production effect of the mold.

Description

A kind of surface carburization process of mould

Technical field

The invention belongs to the surface carburization process of a kind of mould.

Background technology

Mould is the important process equipment producing various industrial products in modern production. Along with socioeconomic development, particularly automobile, household electrical appliances fast development industrial, aerospace, mould industry is had higher requirement. How to improve the problem that the quality of mould, service life and reduction production cost become currently in the urgent need to address. Mould is at work except requiring matrix and having the reasonable coordination of sufficiently high intensity and toughness, and its surface property is most important to service behaviour and the service life of mould. The improvement of mold performance, simple improving of matrix material of dependence is very limited amount of, is also uneconomic, and passes through process for treating surface, often can receive the effect got twice the result with half the effort, this also just process for treating surface in mould produces, obtain the reason that develops rapidly. Steel part is placed in certain active medium and is incubated by thermo-chemical treatment exactly, makes one or more active atomics penetrate into workpiece surface, thus changing the heat-treatment technology method of the chemical composition on top layer, tissue and performance. Different according to the element penetrated into, chemical heat treatment method can be divided into: carburizing, nitriding, carbo-nitriding, boronising, aluminising, vanadinizing etc. Thermo-chemical treatment can be effectively improved the wearability of die surface, fatigue strength, corrosion resistance and antioxygenic property etc. But existing die surface processes technique, and complex process, surface accuracy is not ideal enough, has had a strong impact on mould serviceability and production effect.

Summary of the invention

It is an object of the invention to for Shortcomings part in above-mentioned technology, the present invention provides the surface carburization process of a kind of mould, and technique is simple, can improve surface accuracy performance, improves mould serviceability and production effect.

The technical scheme realizing the object of the invention is as follows:

A kind of surface carburization process of mould, material adopts 12Cr2Ni4A, it is characterised in that adopt following steps:

(1) preparatory stage: carburizing advance line space stove heats up, after furnace temperature is raised to 650-700oC, start electric fan, open recirculated cooling water simultaneously, when furnace temperature reaches 820oC, in stove, instill the cracked gas such as carburizer and methanol carry out sky stove carburizing, furnace temperature reaches carburizing temperature 830-880 DEG C, insulation 2-3h, after furnace gas is normal, enters stove by workpiece, part enters furnace rear, temperature declines, and when temperature is lower than 800oC, drips methanol aerofluxus, when temperature recovery to more than 850oC, except continuing to drip methanol, then add instillation kerosene, and accelerate aerofluxus;

(2) carbon impregnation stage: after furnace temperature arrives carburizing temperature, change the carburizer amount of dripping, continue heat-preservation exhaust 25-38min, take edema caused by disorder of QI analysis, as furnace gas CO2 volume fraction < 0.45%, enter carbon impregnation stage, check furnace temperature, the furnace pressure table check and correction drop amount of dripping every 15min, fluctuation range must not exceed setting �� 5/min;

(3) diffusion phase: ooze by force the infiltration rate in stage by 0.14-0.23mm/h, during diffusion, diffusion period controling of the pressure of the oven is at 50-100Pa, after carburizing completes, temperature is down to 800-820oC, is incubated 20-40min, come out of the stove after part internal and external temperature is uniform and quench and slow cooling, when part is come out of the stove, first powering off, steam vent opened by power failure fan, turn off drop oiler, restart bell and take out workpiece.

The surface carburization process of a kind of mould of the present invention, has technique simple, can improve surface mechanical properties and anti-wear performance, and can reduce the time of carburizing, improves mould serviceability and production effect.

Detailed description of the invention

Below in conjunction with embodiment, the invention will be further described:

A kind of surface carburization process of mould, material adopts 12Cr2Ni4A, adopts following steps:

(1) preparatory stage: carburizing advance line space stove heats up, after furnace temperature is raised to 650-700oC, start electric fan, open recirculated cooling water simultaneously, when furnace temperature reaches 820oC, in stove, instill the cracked gas such as carburizer and methanol carry out sky stove carburizing, furnace temperature reaches carburizing temperature 830-880 DEG C, insulation 2-3h, after furnace gas is normal, enters stove by workpiece, part enters furnace rear, temperature declines, and when temperature is lower than 800oC, drips methanol aerofluxus, when temperature recovery to more than 850oC, except continuing to drip methanol, then add instillation kerosene, and accelerate aerofluxus;

(2) carbon impregnation stage: after furnace temperature arrives carburizing temperature, change the carburizer amount of dripping, continue heat-preservation exhaust 25-38min, take edema caused by disorder of QI analysis, as furnace gas CO2 volume fraction < 0.45%, enter carbon impregnation stage, check furnace temperature, the furnace pressure table check and correction drop amount of dripping every 15min, fluctuation range must not exceed setting �� 5/min;

(3) diffusion phase: ooze by force the infiltration rate in stage by 0.14-0.23mm/h, during diffusion, diffusion period controling of the pressure of the oven is at 50-100Pa, after carburizing completes, temperature is down to 800-820oC, is incubated 20-40min, come out of the stove after part internal and external temperature is uniform and quench and slow cooling, when part is come out of the stove, first powering off, steam vent opened by power failure fan, turn off drop oiler, restart bell and take out workpiece.

The surface carburization process of a kind of mould of the present invention, has technique simple, can improve surface mechanical properties and anti-wear performance, and can reduce the time of carburizing, improves mould serviceability and production effect.

The preferred embodiment of the present invention described in detail above. Should be appreciated that those of ordinary skill in the art just can make many modifications and variations according to the design of the present invention without creative work. All technical staff in the art, all should in the protection domain being defined in the patent claims under this invention's idea on the basis of existing technology by the available technical scheme of logical analysis, reasoning, or a limited experiment.

Claims (1)

1. a surface carburization process for mould, material adopts 12Cr2Ni4A, it is characterised in that adopt following steps:

(1) preparatory stage: carburizing advance line space stove heats up, after furnace temperature is raised to 650-700oC, start electric fan, open recirculated cooling water simultaneously, when furnace temperature reaches 820oC, in stove, instill the cracked gas such as carburizer and methanol carry out sky stove carburizing, furnace temperature reaches carburizing temperature 830-880 DEG C, insulation 2-3h, after furnace gas is normal, enters stove by workpiece, part enters furnace rear, temperature declines, and when temperature is lower than 800oC, drips methanol aerofluxus, when temperature recovery to more than 850oC, except continuing to drip methanol, then add instillation kerosene, and accelerate aerofluxus;

(2) carbon impregnation stage: after furnace temperature arrives carburizing temperature, change the carburizer amount of dripping, continue heat-preservation exhaust 25-38min, take edema caused by disorder of QI analysis, as furnace gas CO2 volume fraction < 0.45%, enter carbon impregnation stage, check furnace temperature, the furnace pressure table check and correction drop amount of dripping every 15min, fluctuation range must not exceed setting �� 5/min;

(3) diffusion phase: ooze by force the infiltration rate in stage by 0.14-0.23mm/h, during diffusion, diffusion period controling of the pressure of the oven is at 50-100Pa, after carburizing completes, temperature is down to 800-820oC, is incubated 20-40min, come out of the stove after part internal and external temperature is uniform and quench and slow cooling, when part is come out of the stove, first powering off, steam vent opened by power failure fan, turn off drop oiler, restart bell and take out workpiece.