阅读说明：本技术 一种主体模具的压铸工艺 (Die casting process of main body die ) 是由 胡海央 于 2020-11-18 设计创作，主要内容包括：本发明公开了一种主体模具的压铸工艺,首先通过浇料口对合模后的腔室填充过滤后的氧气,并从浇料口注入对应的金属液体；接着,根据设定的第一速度,控制压射冲头对所述浇料口进行封闭,同时启动真空泵对所述腔室进行抽真空处理,并根据所述腔室内的压降速率,控制所述压射冲头对所述金属液体进行加压充型；然后,通过调整所述压射冲头位置,对所述金属液体进行保压结晶,并对得到的压铸件进行三次不同的热处理温度下进行回火保温；最后,根据设定的压力值,利用获取的填补料对热处理后的所述压铸件进行表面处理,喷涂检验合格后,封装入库,能够提高压铸模具的产品质量。(The invention discloses a die casting process of a main body die, which comprises the steps of filling filtered oxygen into a cavity after die assembly through a pouring gate, and injecting corresponding metal liquid from the pouring gate; then, according to a set first speed, controlling an injection punch to seal the sprue gate, simultaneously starting a vacuum pump to vacuumize the cavity, and controlling the injection punch to pressurize and mold the metal liquid according to the pressure drop rate in the cavity; then, performing pressure maintaining crystallization on the metal liquid by adjusting the position of the injection punch, and performing tempering and heat preservation on the obtained die casting at three different heat treatment temperatures; and finally, according to the set pressure value, carrying out surface treatment on the die casting subjected to heat treatment by using the obtained filling material, and packaging and warehousing after the spraying inspection is qualified, so that the product quality of the die casting die can be improved.)

1. A die casting process of a main body die is characterized by comprising the following steps:

oxygenating the cavity after die assembly, and injecting corresponding metal liquid from a pouring gate;

controlling an injection punch to enter the cavity at a set speed for filling, and simultaneously vacuumizing the cavity;

performing pressure maintaining crystallization on the metal liquid, and performing heat treatment on the obtained die casting for multiple times;

and carrying out surface treatment on the die casting subjected to heat treatment by using the obtained filling material, and packaging and warehousing after the spraying inspection is qualified.

2. A die casting process of a body mold according to claim 1, wherein the closed chamber is oxygenated and the corresponding molten metal is injected from the sprue, comprising:

after the die-casting die is fixed in position, the die-casting die is closed, and pure oxygen is filled into a cavity in the die-casting die through a pouring gate, wherein the pure oxygen is gas obtained by filtering and removing impurities from oxygen.

3. A die casting process for a body die as set forth in claim 2 wherein controlling the shot punch at a set speed into said chamber for mold filling while evacuating said chamber comprises:

and controlling the injection punch to seal the sprue according to the set first speed, and simultaneously starting a vacuum pump to vacuumize the cavity.

4. A die casting process for a body die as set forth in claim 3 wherein controlling the shot punch at a set speed into said chamber for mold filling while evacuating said chamber comprises:

and controlling the injection punch to pressurize and mold the metal liquid according to the pressure drop rate in the cavity and in an equal ratio or an equal differential speed ratio.

5. A die casting process of a body die according to claim 1, wherein the dwell-pressure crystallization of the metal liquid and the heat treatment of the obtained die casting are performed a plurality of times, including:

and (3) keeping the pressure in the cavity constant by adjusting the position of the injection punch until the metal liquid is crystallized, and tempering and preserving heat at different heat treatment temperatures for three times on the die casting obtained by crystallization.

6. A die casting process of a main body die as claimed in claim 5, wherein the die casting after heat treatment is subjected to surface treatment by using the obtained filler, and after passing the spray inspection, is packaged and warehoused, comprising:

coating and wrapping the preprocessed die casting by using the obtained filling material according to a set pressure value until the filling material is dried and solidified, and carrying out flatness processing on the die casting.

7. A die casting process of a body mold according to claim 6, wherein the die casting after the heat treatment is subjected to a surface treatment by using the obtained filler, and after passing the spray inspection, is packaged and stored, further comprising:

and spraying and drying the die castings, inspecting the density and the surface flatness of the die castings, polishing and shot blasting the die castings qualified in pressure reduction, and packaging and warehousing the die castings qualified in secondary inspection.

Technical Field

The invention relates to the technical field of machining processes, in particular to a die-casting process of a main body die.

Background

Die casting molds are one type of tool for casting metal parts. The basic process of manufacturing the die-casting die comprises the following steps: molten metal is cast at low speed or high speed and filled into the cavity of the mold, the mold has movable cavity surface, and it is pressurized and forged along with the cooling process of the molten metal, so that the shrinkage cavity and shrinkage porosity defects of the blank are eliminated, and the internal structure of the blank reaches the broken crystal grains in the forged state.

After the common die-casting die is die-cast, the phenomenon that the hardness of each part is uneven still exists, the demolding effect and the wear resistance of the die-casting die are affected, the hardness and the strength of the die-casting die need to be adjusted, and the product quality of the die-casting die is reduced.

Disclosure of Invention

The invention aims to provide a die-casting process of a main body die, which improves the product quality of the die-casting die.

In order to achieve the purpose, the invention provides a die casting process of a main body die, which comprises the following steps:

oxygenating the cavity after die assembly, and injecting corresponding metal liquid from a pouring gate;

controlling an injection punch to enter the cavity at a set speed for filling, and simultaneously vacuumizing the cavity;

performing pressure maintaining crystallization on the metal liquid, and performing heat treatment on the obtained die casting for multiple times;

and carrying out surface treatment on the die casting subjected to heat treatment by using the obtained filling material, and packaging and warehousing after the spraying inspection is qualified.

Wherein, oxygenate to the cavity behind the compound die to pour into corresponding metal liquid into from the pouring head, include:

after the die-casting die is fixed in position, the die-casting die is closed, and pure oxygen is filled into a cavity in the die-casting die through a pouring gate, wherein the pure oxygen is gas obtained by filtering and removing impurities from oxygen.

The method comprises the following steps of controlling an injection punch to enter a cavity at a set speed for filling, and vacuumizing the cavity at the same time, and comprises the following steps:

and controlling the injection punch to seal the sprue according to the set first speed, and simultaneously starting a vacuum pump to vacuumize the cavity.

The method comprises the following steps of controlling an injection punch to enter a cavity at a set speed for filling, and vacuumizing the cavity at the same time, and comprises the following steps:

and controlling the injection punch to pressurize and mold the metal liquid according to the pressure drop rate in the cavity and in an equal ratio or an equal differential speed ratio.

The pressure maintaining crystallization is carried out on the metal liquid, and the obtained die casting is subjected to multiple times of heat treatment, and the method comprises the following steps:

and (3) keeping the pressure in the cavity constant by adjusting the position of the injection punch until the metal liquid is crystallized, and tempering and preserving heat at different heat treatment temperatures for three times on the die casting obtained by crystallization.

Carrying out surface treatment on the die casting subjected to heat treatment by using the obtained filling material, and packaging and warehousing after qualified spraying inspection, wherein the method comprises the following steps:

coating and wrapping the preprocessed die casting by using the obtained filling material according to a set pressure value until the filling material is dried and solidified, and carrying out flatness processing on the die casting.

The method comprises the following steps of carrying out surface treatment on the die casting subjected to heat treatment by using the obtained filling material, packaging and warehousing after the spraying inspection is qualified, and further comprises the following steps:

and spraying and drying the die castings, inspecting the density and the surface flatness of the die castings, polishing and shot blasting the die castings qualified in pressure reduction, and packaging and warehousing the die castings qualified in secondary inspection.

The die casting process of the main body die comprises the steps of firstly filling filtered oxygen into a cavity after die assembly through a pouring gate, and injecting corresponding metal liquid from the pouring gate; then, according to a set first speed, controlling an injection punch to seal the sprue gate, simultaneously starting a vacuum pump to vacuumize the cavity, and controlling the injection punch to pressurize and mold the metal liquid according to the pressure drop rate in the cavity; then, performing pressure maintaining crystallization on the metal liquid by adjusting the position of the injection punch, and performing tempering and heat preservation on the obtained die casting at three different heat treatment temperatures; and finally, according to the set pressure value, carrying out surface treatment on the die casting subjected to heat treatment by using the obtained filling material, and packaging and warehousing after the spraying inspection is qualified, so that the product quality of the die casting die can be improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic step diagram of a die casting process of a main body die according to a first embodiment of the present invention.

Fig. 2 is a schematic step diagram of a die casting process of a main body die according to a second embodiment of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

Referring to fig. 1, a first embodiment of the invention provides a die casting process of a main body die, which includes the following steps:

and S101, oxygenating the cavity after mold closing, and injecting corresponding metal liquid from a pouring gate.

Specifically, after the position of the die-casting die is fixed, the die-casting die is closed to form a cavity and a pouring gate, pure oxygen is filled into a cavity in the die-casting die through a pouring gate, wherein the pure oxygen is gas obtained by filtering and removing impurities from oxygen, and the obtained oxygen can be used for removing impurities in the oxygen and objects which can influence the die-casting material, such as reaction with the die-casting material, or drives the material into a chain reaction, produces harmful or useless by-products, affects the quality of the die casting, and utilizes the filled pure oxygen, the dust is removed from the pouring port and the pouring gate to ensure the cleanness of the pouring port and the pouring gate, and then injecting the smelted corresponding metal liquid into the chamber through the pouring gate, so that the purity and quality of the metal liquid are ensured. Oxygen is filled into the cavity to replace air in the cavity, so that the oxygen in the cavity reacts with the molten metal to generate oxide particles which are distributed in the casting in a dispersion manner, and the effect of eliminating pores of the casting is achieved.

And S102, controlling the injection punch to enter the cavity at a set speed for filling, and vacuumizing the cavity at the same time.

After the liquid is finished, pressing an injection punch into the cavity at a first speed, closing the sprue gate, stopping oxygenating the cavity and the pressure chamber (the cavity comprises the cavity and the pressure chamber), and simultaneously starting a vacuum pump to vacuumize the cavity and the pressure chamber; when the punch head travels to a preset position in the pressure chamber at a first preset speed, the injection punch head is controlled to pressurize and fill the metal liquid at an equal or unequal speed ratio according to the pressure drop rate in the chamber, and the travel speed of the injection conflict is controlled to be inversely proportional to the pressure drop, so that the pressure in the chamber is maintained, and the metal liquid can fill the whole chamber at a stable pressure.

S103, carrying out pressure maintaining crystallization on the metal liquid, and carrying out heat treatment on the obtained die casting for multiple times.

Specifically, the injection punch head transmits pressure to the cavity through the solidified residual material and the metal at the intersection part, so that the solidified metal is crystallized under the pressure; and materials are supplemented when the interior of the product is cooled and shrunk through pressure maintaining, shrinkage cavities are prevented and reduced, and the density of the product is improved.

S1, heating the die-casting die to 500-550 ℃, and then preserving heat. In the embodiment, the salt bath furnace is used for heating the die-casting die, and the heat preservation time after the die-casting die is heated to 500-550 ℃ is 2-3.5 min/mm.

S2, continuously heating the die-casting die treated in the step S1 to 800-850 ℃, and then preserving heat. In the embodiment, the salt bath furnace is used for heating the die-casting die, and the heat preservation time after heating to 800-.

S3, further heating the die-casting die treated in the step S2 to 1020-1040 ℃, and then preserving heat. In the embodiment, the salt bath furnace is used for heating the die-casting die, and the heat preservation time after the die-casting die is heated to 1020-1040 ℃ is 0.5-0.6 min/mm.

S4, carrying out oil cooling or air cooling on the die-casting die treated in the step S3 to 370-420 ℃, and then carrying out heat preservation. Preferably, the die-casting die is kept warm for 5-20min after being cooled to the temperature of 420 ℃ by oil or gas.

And S5, cooling the die-casting die treated in the step S4 in air. The hardness of the die-casting die after air cooling is 44-48 HRC.

The die-casting die is heated to 550 ℃, 800, 850 ℃ and 1020, 1040 ℃ respectively, then is insulated, is cooled by oil or air to 370, 420 ℃ and then is air-cooled, so that the die-casting die quickly avoids a bainite structure transformation area and enters a martensite structure transformation area, the microstructure of the die-casting die is transformed into martensite as much as possible, carbides, bainite and residual austenite precipitated along a grain boundary are reduced or avoided, the hardness of the die-casting die is uniform, the hardness difference of each part is small, and the demolding effect and the wear resistance of the die-casting die are improved; the residual stress is eliminated through three times of tempering treatment, the die-casting die is prevented from deforming and cracking, the hardness and the strength of the die-casting die are adjusted, and the product quality of the die-casting die is improved. The heat treatment process of the die-casting die is simple in treatment process and strong in operability, and is suitable for large-scale production of the die-casting die.

And S104, performing surface treatment on the die casting after heat treatment by using the obtained filling material, and packaging and warehousing after the spraying inspection is qualified.

Specifically, coating and wrapping the die casting after pretreatment by using the obtained filling material according to a set pressure value, and enabling the obtained filling material to conveniently enter holes of the die casting under a certain pressure, wherein the pretreatment is to carry out oil stain removal, rust corrosion removal, old paint film removal and moisture removal treatment on the surface of the die casting, and the surface of the die casting is completely treated, so that the adhesion between an ash material and the die casting can be effectively improved, and the ash material is more firmly filled in the holes of the die casting; the filling material is an atomic ash or aluminum repairing agent. The putty has the advantages of fine gray matter, easy scraping and coating, easy filling, easy polishing, high drying speed, strong adhesive force, high hardness, difficult scratching, good flexibility, heat resistance, difficult cracking and foaming, short construction period and the like, and is particularly suitable for filling holes of die castings. The aluminum repairing agent is suitable for repairing various metal surfaces, vertical surfaces, convex surfaces or concave surfaces, has high and low temperature resistance (about (-60 ℃ to +80 ℃), has excellent physical and mechanical properties, bonding strength, electrical insulation performance, chemical corrosion resistance, heat resistance and chemical stability, has low shrinkage and water absorption, has high mechanical strength, is mixed with two components, is hardened to form a firm material similar to a metal shape, can be machined, and has the characteristics of rapidness, economy, durability and the like.

After the die casting is wrapped by the filling material, baking the die casting for 30-60 minutes at the temperature of 200-400 ℃ to release residual water vapor and air in the ash material as much as possible; and after the ash of the die casting is dried and solidified, carrying out flatness treatment on the die casting, namely, smoothing the convex objects or concave positions formed on the die casting through baking until the surfaces of the convex objects or the concave positions are dry and flat, and polishing the surfaces of the convex objects or the concave positions of the die casting by using a scraper or sand paper to ensure that surface bulges are removed, filling holes which are not completely covered, so that the whole surface of the die casting is flat, and almost no bulges appear in the subsequent baking spray coating process.

Spraying the die casting to obtain a finished product; painting is the dispersion of a liquid coating (i.e. paint) into paint mist particles by means of compressed air which adhere to the surface of the die cast. The powder spraying is that powder fog particles are dispersed into powder fog by means of compressed air under the action of high-voltage static electricity and are adsorbed on the surface of a die casting through an electric field. Powder spraying, also known as electrostatic powder spraying, cannot be simply accomplished with a paint gun. The electrostatic powder spraying equipment generally comprises a powder supply barrel (supplying powder by using compressed air), a high-voltage electrostatic generator and an electrostatic powder spraying gun; according to different spraying treatments, the sprayed layer can be naturally dried, and the baking treatment can also be carried out in an oven. And after the density and the surface flatness of the die casting are inspected, the die casting which is qualified in decompression is polished and shot-blasted, and after the die casting is qualified again, the die casting is packaged and put in storage, so that the bulging phenomenon of the die casting can be avoided, and the product yield is improved.

Referring to fig. 2, a second embodiment of the invention provides a die casting process of a main body die, which includes the following steps:

s201, debugging, installing and preprocessing a die casting machine, and obtaining metal raw materials for smelting.

Specifically, before die casting, the die casting machine is tested for various functions to ensure the normal operation of the die casting machine; then, correctly installing the die-casting die; putting the required materials into a melting furnace according to a specific mass percentage for configuration; during configuration, the smelting temperature and the electromagnetic convection stirring temperature are set according to specific production; the time of injecting oxygen lasts 10-15 seconds, the pressure is 0.8-1.0MPa, and the temperature and the pressure are both interval values, and only the interval can be properly changed.

Preheating a die and discharging: preheating a mould, and putting the smelted material into the mould; the preheating temperature is kept between 170 ℃ and 210 ℃, and when the material is preheated in the temperature range, the phenomenon that the metal liquid after the material is configured is rapidly chilled and loses fluidity quickly to cause that the casting cannot be molded or the line shrinkage is increased due to the chilling to cause cracks and cracks even if the casting is molded is avoided; the die casting die is prevented from expanding and cracking due to shock heating, and the service life of the die casting die is prolonged; meanwhile, preheating is beneficial to removing gas in the cavity, and the gas density in the cavity is reduced, so that a casting with smooth surface, clear outline and compact structure is obtained.

The contents described in the embodiments of S202 to S205 are the same as those described in the embodiments of S101 to S104 in the first embodiment, and are not described herein again.

The die casting process of the main body die comprises the steps of firstly filling filtered oxygen into a cavity after die assembly through a pouring gate, and injecting corresponding metal liquid from the pouring gate; then, according to a set first speed, controlling an injection punch to seal the sprue gate, simultaneously starting a vacuum pump to vacuumize the cavity, and controlling the injection punch to pressurize and mold the metal liquid according to the pressure drop rate in the cavity; then, performing pressure maintaining crystallization on the metal liquid by adjusting the position of the injection punch, and performing tempering and heat preservation on the obtained die casting at three different heat treatment temperatures; and finally, according to the set pressure value, carrying out surface treatment on the die casting subjected to heat treatment by using the obtained filling material, and packaging and warehousing after the spraying inspection is qualified, so that the product quality of the die casting die can be improved.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.