A horizontal high-vacuum pressure casting injection device and die-casting method with pressurized solidification

Abstract

The present invention discloses a horizontal high-vacuum pressure casting injection device with pressure-boosted solidification and a die-casting method. The horizontal high-vacuum pressure casting injection device with pressure-boosted solidification includes: a pressure chamber, an injection punch, an injection piston rod, a diverter cone, and an injection device controller; the pressure chamber is provided with a pouring port communicating with a riser pipe and a vacuum extraction port communicating with a vacuum extraction device; the injection punch is arranged inside the pressure chamber and connected to the injection piston rod outside the pressure chamber; a four-stage seal is arranged in the gap between the outer surface of the injection punch and the inner wall of the pressure chamber; the injection end face of the punch has been pre-treated; an oily inert gas channel is arranged inside the injection piston rod and the punch; the diverter cone is arranged on the other side of the injection punch to open and close the pressure chamber; the injection device controller is electrically connected to the injection piston rod and the diverter cone respectively. The present invention can achieve good sealing performance and flexible passability of the injection device; while meeting the process requirements of high-vacuum pressure casting, it realizes pressure-boosted solidification of the molten metal, reduces the probability of shrinkage porosity formation during solidification of the molten metal, and produces castings with fine and defect-free structures.

Description

Technical Field

[0001] The present invention relates to the technical field of high-vacuum pressure casting, and particularly relates to an injection device for pressurized solidification that is easy to seal, resistant to high pressure, and conducts oil-free inert gas, as well as a die-casting method, which is suitable for die-casting and extrusion. Background Art

[0002] High-vacuum die-casting technology is an advanced die-casting process that eliminates or significantly reduces the pores and dissolved gases in die-cast parts by evacuating the gas in the die cavity during the die-casting process, thereby improving the mechanical properties and surface quality of die-cast parts. As an advanced special die-casting process, it enables the molten metal to fill the cavity under vacuum conditions and the vacuum pressure in the die cavity to be maintained below 5 KPa. High-vacuum die-casting has the same advantages as ordinary die-casting methods, but the internal quality and mechanical properties of the castings are greatly improved. The key technologies of high-vacuum die-casting are the sealing performance of the punch and the high-pressure effect generated by the punch, that is, how to ensure the vacuum degree of the pressure chamber and the die cavity and the end of the punch extrudes the casting with ultra-high pressure after the filling is completed, so as to reduce the probability of shrinkage porosity formation during solidification and obtain castings with fine and defect-free structures.

[0003] The research and development of the injection device for high-vacuum die-casting equipment has a long history, as described in Cited Patent 1 to Cited Patent 3.

[0004] Cited Patent 1. Chinese Patent: CN 103817308B, a punch for high-vacuum die-casting and a lubricating device for the punch. To extend the service life of the punch and ensure effective sealing between the punch and the pressure chamber, while necessary cooling and lubrication are carried out on the punch to meet the high sealing performance and good lubrication performance required by high-vacuum die-casting. This method is prone to having lubricant adhering to the places where lubrication is not required in the injection mechanism due to the use of atomized lubricant, making it difficult to clean after die-casting.

[0005] Cited Patent 2. Japanese Patent: 2007-268550A, an injection device in the invented high-vacuum die-casting method, which adopts a moving piston structure and uses the pressure of the molten metal to drive the injection punch to move. This method has the drawback that the molten metal enters the clearance between the punch and the pressure chamber under high pressure and jams the punch.

[0006] Cited Patent 3. Chinese Patent: CN106552917B, a high-vacuum die-casting mold for alloy die-casting forming, which discloses an injection device that realizes the sealing between the pressure chamber and the injection rod through a rubber ring. This method does not protect the rubber ring and is extremely prone to damage in a high-temperature and high-pressure environment, with a low service life.

[0007] In order to improve the quality and reliability of vacuum pressure casting while maintaining economy and production efficiency, the present inventor has separately developed a complete set of high-vacuum die-casting equipment and casting method, as well as a complete set of high-vacuum extrusion equipment and casting method. In the above two sets of equipment, requirements such as high sealing performance and high pressure resistance are put forward for the injection punch. To meet the technological requirements of the above equipment, while enhancing the sealing effect, without affecting the service life of the sealing element and the injection punch, an injection device applicable to high-vacuum pressure casting and a casting method of pressurized solidification have been developed. Summary of the Invention

[0008] (I) Technical Problems to be Solved

[0009] The technical problem to be solved by the present invention is that while meeting the general technological requirements of the injection punch, such as transmitting pressure, conveying molten metal, and wear resistance, in view of the characteristics of high-vacuum pressure casting, the reliability of the injection punch seal is particularly strengthened and the injection pressure is increased. It is necessary to invent corresponding injection devices and die-casting methods to meet the requirements of enhancing the punch seal and increasing the casting pressure, while enhancing the service life of the sealing element and the injection punch.

[0010] (II) Technical Solutions

[0011] To solve the above problems, the present invention provides a pressurized solidification horizontal high-vacuum pressure casting injection device and a die-casting method.

[0012] As the first aspect of the present invention, a design scheme of the injection device for high-vacuum pressure casting with pressurized solidification of the present invention is proposed. According to an embodiment of the present invention, the injection device includes: a pressure chamber, which is horizontally arranged and fixedly positioned for storing high-temperature molten metal; a pouring port is provided below the pressure chamber, and the pouring port is communicated with a riser pipe; a vacuum pumping port is provided above the pressure chamber, and the vacuum pumping port is communicated with a vacuum pumping device; an injection punch, which is located inside the pressure chamber, and one side of the injection punch is threadedly connected with an injection piston rod extending to the outside of the pressure chamber; a flow dividing cone is provided on the other side of the injection punch; the movement of the injection piston rod drives the injection punch to move inside the pressure chamber; a flow dividing cone, which moves along the length direction of the pressure chamber; when the flow dividing cone moves towards the pressure chamber to the limit position, the flow dividing cone closes one side of the pressure chamber; when the flow dividing cone moves in the opposite direction of the pressure chamber, the pressure chamber gradually opens; the injection device controller is respectively connected to the injection piston rod and the flow dividing cone, and simultaneously controls the movement of the injection piston rod and the flow dividing cone.

[0013] In addition, the injection device according to the above embodiment of the present invention further has the following additional technical features:

[0014] According to an embodiment of the present invention, the injection punch in the injection device further includes: the injection punch can generate a working pressure of 0 to 200 Mpa under the push of the injection piston rod, so stronger sealing performance is required. There is a four-stage seal provided in the gap between the outer surface of the injection punch and the inner wall of the injection chamber. From the side of the injection piston rod to the side of the sub-spindle, they are combined expansion ring seal B6, heat-resistant washer seal A7, heat-resistant washer seal B8, and combined expansion ring seal A5 respectively. The two combined expansion ring seals are composed of a beryllium bronze expansion ring 52 and a die steel expansion ring 51. The setting of the four-stage seal better enhances the reliability of the punch seal, and still can meet the seal effect of the punch after the pressure is increased, preventing external gas from entering the inner cavity of the injection chamber. At the same time, the combined expansion rings at both ends can prevent the molten metal from infiltrating into the gap between the punch and the injection chamber.

[0015] According to an embodiment of the present invention, the injection punch in the injection device further includes: to increase the service life of the sealing element under high temperature and high pressure, radial blind holes A210, radial blind holes B220, radial blind holes C230, and radial blind holes D240 are symmetrically arranged on the lower side and the upper side of the outer cylindrical surface of the injection punch; radial blind holes A210 and radial blind holes B220 are both communicated with the axial blind hole E260 inside the injection punch; radial blind holes C230 and radial blind holes D240 are both communicated with the axial blind hole F250 inside the injection punch; the axial blind hole E260 is further connected to the axial channel J310 inside the injection piston rod; the axial blind hole F250 is further connected to the axial channel H320 inside the injection piston rod; the ends of the axial channel J310 and the axial channel H320 are connected to an oil-based inert gas supply device; the opening positions of the radial blind holes A210 and radial blind holes C230 are located in the middle of the heat-resistant washer seal A7; the opening positions of the radial blind holes B220 and radial blind holes D240 are located in the middle of the heat-resistant washer seal B8; the oil and gas inert gas filled into the middle of the heat-resistant washer seal A7 and the heat-resistant washer seal B6 can play roles such as lubrication and anti-friction, auxiliary cooling and temperature reduction, and shock absorption and buffering.

[0016] According to an embodiment of the present invention, the injection punch in the injection device further includes: enhancing the service life of the injection punch. The injection end face of the injection punch is not a plane. As a preferred solution, a grid-shaped groove is provided on the end face, and the center distance between adjacent grids of the grid-shaped groove is less than 2 - 10 mm; the width of the spiral groove is 100 - 500 μm, and the depth of the groove is 10 - 100 μm. This solution is suitable for a relatively low-pressure environment in the injection chamber, that is, the casting pressure is less than 100 Mpa; as a preferred solution, a plurality of circular concentric grooves are provided on the end face; the diameter difference between two adjacent circular concentric grooves is 2 - 10 mm; the width of the groove is 50 - 500 μm, and the depth of the groove is 10 - 100 μm. This solution is suitable for a relatively medium-pressure environment in the injection chamber, that is, the casting pressure is between 100 - 150 Mpa; as a preferred solution, a spiral groove is provided on the end face; the center distance between two adjacent arcs of the spiral groove is less than 5 - 10 mm; the width of the spiral groove is 100 - 500 μm, and the depth of the groove is 10 - 100 μm. This solution is suitable for a high-pressure environment in the injection chamber, that is, the casting pressure reaches 200 Mpa and above; among them, the processing of the grooves all adopts laser processing to meet the accuracy requirements and processing performance requirements.

[0017] According to an embodiment of the present invention, the sprue bush in the injection device further includes: the cone of the sprue bush is designed in a trapezoidal shape with a narrower upper part and a wider lower part in cross section, and the bottom angle is set between 45° and 60°. The design of this sprue bush shape can ensure that when the sprue bush is not fully opened, the residual gas in the injection chamber is pumped away by the vacuum device in the cavity.

[0018] According to an embodiment of the present invention, the coating on the injection end face of the injection punch in the injection device further includes: as a preferred solution, the thickness of the coating on the injection end face is controlled between 0.1 - 0.2 mm, and the separation of the punch from the casting can still be ensured after pressure boosting.

[0019] In the second aspect of the present invention, the present invention proposes a die-casting method.

[0020] According to an embodiment of the present invention, the method uses the above-mentioned high-vacuum pressure casting injection device with pressurized solidification, and includes: (a) Before high-vacuum pressure casting, a high-temperature and high-pressure in-situ coating is sprayed on the injection end face of the injection punch. The thickness of the sprayed in-situ coating layer is controlled between 0.1 and 0.2 mm, which facilitates the separation of the punch from the casting and can better protect the punch; the pressure chamber is closed (including the shut-off of the diverter cone + the injection punch advances to close the pouring port of the pressure chamber), and the oil-based inert gas supply device is started to work. The oil-based inert gas flows through the blind holes of the injection piston rod and the injection punch to reach the middle of the two sealing gaskets, which lubricates, dampens, and cools the gaskets, can better protect the sealing elements, and at the same time, the generated pressure can prevent the molten metal in the pressure chamber from entering the mating gap between the pressure chamber and the punch and jamming the punch. (b) The vacuum port of the pressure chamber is opened, and vacuum pumping starts. The vacuum pumping device can achieve a vacuum degree below 5 kPa in the pressure chamber; after the vacuum pumping in the pressure chamber is completed, the vacuum port of the pressure chamber is closed, and the injection piston rod is pushed back by the injection device controller to drive the injection punch to retreat, and the pouring port of the pressure chamber is opened. Under the action of the pressure difference, the molten metal fills the pressure chamber. (c) At the same time as the pouring port of the pressure chamber is opened, the injection device controller controls the diverter cone to retreat and move 10-20 mm and stop, and controls the injection piston rod to drive the injection punch to slowly advance to re-close the pouring port of the pressure chamber, ensuring that the residual gas in the pressure chamber completely escapes, and the molten metal has not yet passed over the diverter cone. Then the diverter cone is completely opened, and the injection punch quickly advances to the end face of the pressure chamber. When it is preset that the injection punch reaches the end face of the pressure chamber, the instantaneous pressure of the punch reaches between 100 and 200 Mpa to complete the injection.

[0021] According to an embodiment of the present invention, the oil-based inert gas in the method further includes that the oil in the oil-based inert gas is micro-droplets of 10W-40 SAE lubricating oil, and the inert gas is argon.

[0022] (III) Beneficial effects

[0023] While meeting the general process requirements of the injection punch, such as transmitting pressure, conveying molten metal, and wear resistance, the present invention specifically enhances the reliability of the seal of the injection punch and increases the injection working pressure according to the characteristics of high-vacuum pressure casting. The vacuum degree of the mold cavity can reach below 5 kPa. By the smooth convenience of the through-hole of the pressure chamber and introducing the oil-based inert gas, it can play roles such as lubrication and anti-friction, auxiliary cooling and temperature reduction, and shock absorption and buffering, enhancing the service life of the sealing elements; through the design of the end face of the injection punch, the injection punch is easily separated from the casting, and at the same time, stress concentration phenomenon is not likely to occur on the end face under the high-pressure and high-temperature environment, increasing the service life of the punch. It fully meets the process requirements and can simultaneously achieve the effect of enhancing the solidification of the molten metal under pressure and reducing defects. Description of the drawings

[0024] Figure 1It is a schematic structural diagram of the injection device of the present invention;

[0025] Figure 2 It is a schematic structural diagram of the combined expansion ring of the present invention.

[0026] Figure 3 It is a schematic structural diagram of the groove on the injection end face of the punch of the present invention

[0027] In the figure: 1, pressure chamber; 2, injection punch; 3, injection piston rod; 4, sprue divider; 5, combined expansion ring A; 51, die steel ring; 52, beryllium bronze expansion ring; 6, combined expansion ring B; 7, heat-resistant sealing washer A; 8, heat-resistant sealing washer B; 9, injection device controller; 110, pouring gate; 120, vacuum extraction port; 210, radial blind hole A; 220, radial blind hole B; 230 radial blind hole C; 240, radial blind hole D; 250, axial blind hole F; 260, axial blind hole E; 310, axial blind hole J; 320, axial blind hole H. Detailed implementation manners

[0028] The following combines the drawings and embodiments to further describe in detail the specific implementation manners of the present invention. The following embodiments are used to illustrate the present invention, but are not used to limit the scope of the present invention.

[0029] Embodiment 1.

[0030] In one aspect of the present invention, the present invention provides a horizontal high-vacuum pressure casting injection device with pressurized solidification. Refer to Figure 1 , and a detailed description of the injection device of the present invention is given.

[0031] According to an embodiment of the present invention, as Figure 1 shown, the injection device includes: a pressure chamber 1, an injection punch 2, an injection piston rod 3, a sprue divider 4, a combined expansion ring A 5, a combined expansion ring B 6, a sealing washer A 7, a sealing washer B 8, and an injection device controller 9. Among them, a pouring gate 110 is provided below the pressure chamber 1, and the pouring gate is communicated with a lifting pipe; a vacuum extraction port 120 is provided above the pressure chamber, and the vacuum extraction port 120 is communicated with a vacuum extraction device; the injection punch 2 is located inside the pressure chamber 1, and one side of the injection punch 2 is threadedly connected to the injection piston rod 3 extending outside the pressure chamber; a sprue divider 4 is provided on the other side of the injection punch 2; the movement of the injection piston rod 3 drives the injection punch 2 to move inside the pressure chamber 1; the sprue divider 4 moves along the length direction of the pressure chamber 1; when the sprue divider 4 moves towards the pressure chamber 1 to the limit position, the sprue divider 4 completely closes one side of the pressure chamber 1; when the sprue divider 4 moves in the opposite direction of the pressure chamber 1, the pressure chamber 1 gradually opens; the injection device controller 9 is electrically connected to the injection piston rod 3 and the sprue divider 4 respectively, and simultaneously controls the movement of the injection piston rod 3 and the sprue divider 4;

[0032] According to an embodiment of the present invention, as Figure 1As shown, a four - stage seal is provided in the gap between the outer surface of the injection punch 2 and the inner wall of the injection chamber 1. From the side of the injection piston rod 3 to the side of the diverter cone 4, they are the combined expansion ring B6, heat - resistant sealing washer A7, heat - resistant sealing washer B8, and combined expansion ring A5; as Figure 2 shown, both the combined expansion ring A5 and the combined expansion ring B6 are composed of a beryllium bronze expansion ring 52 and a die steel expansion ring 51. Both ends of the two expansion rings have an inclination angle of 5×10 degrees, and the "Z" - shaped gap cut by wire - cutting is not greater than 0.1 mm. The setting of the four - stage seal shares the sealing pressure of each sealing element, increases the service life of each sealing element, and the combined expansion ring seal can also play a role in accelerating the cooling of the punch.

[0033] According to an embodiment of the present invention, as Figure 1 shown, radial blind holes A210, radial blind holes B220, radial blind holes C230, and radial blind holes D240 are symmetrically arranged on the lower and upper sides of the outer cylindrical surface of the injection punch 2; radial blind holes A210 and radial blind holes B220 are both connected to the transverse blind hole E260 inside the injection punch 2, and radial blind holes C230 and radial blind holes D240 are both connected to the transverse blind hole F250 inside the injection punch 2; the transverse blind hole E260 is further connected to the axial channel J310 inside the injection piston rod 3, and the transverse blind hole F250 is further connected to the axial channel H320 inside the injection piston rod 3; the ends of the axial channel J310 and the axial channel H320 are connected to an oily inert gas supply device; the opening positions of the radial blind holes A210 and radial blind holes D240 are located in the middle of the heat - resistant sealing washer A7; the opening positions of the radial blind holes B220 and radial blind holes C230 are located in the middle of the heat - resistant sealing washer B8;

[0034] According to the inventor's research findings, when the pressure of the mixed gas output by the oily inert gas supply device is 0.1 - 10 Mpa, a mixed gas of 10W - 40 SAE lubricating oil micro - droplets and argon is used, the total volume of the lubricating oil micro - droplets accounts for not less than 10% of the total volume of the mixed gas, and the diameter of the lubricating oil micro - droplets is 5 - 50 microns, the best functions of lubrication and friction reduction, auxiliary cooling and temperature reduction, and shock absorption and buffering can be obtained, and it can play a good protective role for the heat - resistant sealing washer.

[0035] According to an embodiment of the present invention, as Figure 1 shown, the combined expansion rings A5 and B6 are respectively installed at both ends of the injection punch 2 and are flush with the end face of the injection punch 2; the heat - resistant sealing washers A7 and B8 are installed on both sides of the outer circumferential surface of the injection punch 2, and the distance from the end face of the injection punch 2 is greater than 100 mm;

[0036] According to an embodiment of the present invention, as Figure 3As shown, the injection end face of the injection punch 2 is not a plane, but is provided with spiral grooves; the center distance between adjacent two arcs of the spiral groove is less than 5 - 10 mm; the width of the spiral groove is 100 - 500 μm, and the groove depth is 10 - 100 μm. At this time, the casting pressure after boosting reaches 200 Mpa and above.

[0037] According to an embodiment of the present invention, as Figure 1 shown, the cross-sectional shape of the dividing cone 4 is a trapezoid with an inclined side, and the bottom angle is set to 45°, which can ensure that when the dividing cone is not fully opened, the residual gas in the pressure chamber is evacuated by the vacuum device in the cavity.

[0038] In summary, according to an embodiment of the present invention, the present invention provides a horizontal high-vacuum pressure casting injection device with pressure boosting and solidification. During the process of vacuum die casting using this device, through the treatment of four-stage sealing, the vacuum pumping effect on the pressure chamber and the cavity can be further ensured, and the porosity content of the castings poured under high vacuum can be effectively reduced. To make the heat-resistant washer in the four-stage sealing work better, grooves are provided in the injection piston rod and the punch. By inputting oily inert gas into the middle of the washer, the washer can obtain the best lubrication, wear reduction, shock absorption and buffering effects, and at the same time has a cooling effect on the punch, which can effectively improve the service life of the washer and the punch in a high-pressure and high-temperature environment. Through the treatment of the punch end face, better separation between the punch and the casting after die casting can be further ensured. The coating sprayed on the punch end face is not easy to fall off, and can be re-sprayed after multiple productions, effectively shortening the cycle of high-vacuum die casting, thus manufacturing castings more efficiently. At the same time, under high temperature and high pressure, stress concentration does not easily occur on the punch end face, increasing the service life of the punch.

[0039] In one aspect of the present invention, the present invention provides a high-vacuum die casting method. Referring to Figure 1 ..., the high-vacuum die casting method of the present invention will be described in detail. It should be noted that "high vacuum" herein refers to a vacuum degree below 5 kPa. According to an embodiment of the present invention, referring to Figure 1 ..., this method uses the above-mentioned injection device, and includes:

[0040] S100: Before high-vacuum pressure casting, a high-temperature and high-pressure in-situ coating is sprayed on the injection end face of the injection punch 2, and the thickness of the sprayed in-situ coating layer is controlled between 0.1 and 0.2 mm; the pressure chamber 1 is closed (including the closing of the dividing cone 4 + the advancement of the injection punch 2 to close the pouring port 110 of the pressure chamber), and the oily inert gas supply device is started to work. The oily inert gas flows through the blind holes of the injection piston rod 3 and the injection punch 2 to reach the middle parts of the sealing washer A 7 and the sealing washer B 8.

[0041] S200: The vacuum extraction port 120 of the pressure chamber 2 is opened to start vacuum extraction. The vacuum extraction device can reduce the vacuum degree in the pressure chamber to below 5 kPa. After the vacuum extraction in the pressure chamber is completed, the vacuum extraction port 120 of the pressure chamber is closed. The injection piston rod 3 is controlled by the injection device controller 9 to push back, driving the injection punch 2 to retract, and the pouring port 110 of the pressure chamber is opened. Under the action of the pressure difference, the molten metal fills the pressure chamber 1.

[0042] S300: While the pouring port 110 of the pressure chamber is opened, the injection device controller 9 controls the sprue bushing 4 to move and stop at 1 / 4 to 1 / 3 of the total stroke. The injection piston rod 3 is controlled to drive the injection punch 2 to advance at a speed of 0.1 - 0.2 m / s to re-close the pouring port 110 of the pressure chamber, ensuring that the residual gas in the pressure chamber 1 completely escapes, and the molten metal has not yet passed over the sprue bushing 4. Then the sprue bushing 4 is fully opened, and the injection punch 2 advances to the end face of the pressure chamber 1 at a speed of 1 - 2 m / s. When it is preset that the injection punch 2 reaches the end face of the pressure chamber 1, the instantaneous pressure of the punch reaches between 100 and 200 Mpa to complete the injection.

[0043] According to an embodiment of the present invention, the high-vacuum die-casting method may further include:

[0044] S400: After casting is completed, during the process of the injection punch 2 returning to the sealing position, it can run back and forth several times. The die steel expansion rings in the combined expansion rings A5 and B6 can be used to scrape the inner wall of the pressure chamber 1 to clean the metal chips and the like remaining inside the pressure chamber 1.

[0045] Embodiment Two.

[0046] The distinguishing technical features between Embodiment Two and Embodiment One are as follows:

[0047] The injection end face of the injection punch is provided with a plurality of circular concentric grooves; the diameter difference between adjacent two circular concentric grooves is 2 - 10 mm; the groove width is 50 - 500 microns, the groove depth is 10 - 100 microns, and the casting pressure after pressurization reaches between 100 and 150 Mpa.

[0048] Embodiment Three.

[0049] The distinguishing technical features between Embodiment Three and Embodiments One and Two are as follows:

[0050] The injection end face of the injection punch is provided with a cross-shaped groove, and the adjacent center distance of the cross-shaped groove is less than 2 - 10 mm; the width of the spiral groove is 100 - 500 microns, the groove depth is 10 - 100 microns, and the casting pressure after pressurization is less than 100 Mpa.

[0051] The above embodiments are only used to illustrate the present invention and are not intended to limit the present invention. Those of ordinary skill in the relevant technical field can also make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also fall within the scope of the present invention. The scope of patent protection of the present invention shall be defined by the claims.

Claims

1. A high-vacuum pressure casting pressurization and solidification method, characterized in that, Horizontal high-vacuum pressure casting injection device with pressure-boost solidification, the device comprising: a pressure chamber (1), an injection punch (2), an injection piston rod (3), a diverter cone (4) and an injection device controller (9); the pressure chamber (1) is horizontally arranged and fixedly positioned for storing high-temperature liquid metal; a pouring port (110) is provided below the pressure chamber (1), and the pouring port (110) is communicated with a riser tube; a vacuum extraction port (120) is provided above the pressure chamber (1), and the vacuum extraction port (120) is communicated with a vacuum extraction device; the injection punch (2) is located inside the pressure chamber (1), and one side of the injection punch (2) is threadedly connected to the injection piston rod (3) extending outside the pressure chamber (1); a diverter cone (4) is provided on the other side of the injection punch (2); the movement of the injection piston rod (3) drives the injection punch (2) to move inside the pressure chamber (1); the diverter cone (4) moves along the length direction of the pressure chamber (1); when the diverter cone (4) moves towards the pressure chamber (1) to the limit position, the diverter cone (4) closes one side of the pressure chamber (1); when the diverter cone (4) moves in the opposite direction of the pressure chamber, the pressure chamber (1) gradually opens; the injection device controller (9) is electrically connected to the injection piston rod (3) and the diverter cone (4) respectively, and controls the movement of the injection piston rod (3) and the diverter cone (4) simultaneously; a four-stage seal is provided in the gap between the outer surface of the injection punch (2) and the inner wall of the pressure chamber (1), and from the side of the injection piston rod to the side of the diverter cone are a combined expansion ring B (6), a heat-resistant sealing washer A (7), a heat-resistant sealing washer B (8) and a combined expansion ring A (5); the combined expansion ring A (5) and the combined expansion ring B (6) are composed of a beryllium bronze expansion ring (52) and a die steel ring (51); Radial blind holes A (210) and radial blind holes B (220) are provided on the lower side of the outer cylindrical surface of the injection punch; both of the two radial blind holes are communicated with an axial blind hole E (260) inside the injection punch (2); the axial blind hole E (260) is further connected to an axial blind hole J (310) inside the injection piston rod (3); the end of the axial blind hole J (310) is connected to an oily inert gas supply device; the opening position of the radial blind hole A (210) is located in the middle of the heat-resistant sealing washer A (7); the opening position of the radial blind hole B (220) is located in the middle of the heat-resistant sealing washer B (8); the oily inert gas supply device outputs a mixed gas of lubricating oil droplets and inert gas, wherein the total volume of the lubricating oil droplets accounts for not less than 10% of the total volume of the mixed gas, and the diameter of the lubricating oil droplets is 5 - 50 microns; The method includes the following steps: (a) Before high-vacuum pressure casting, spray an in-situ coating resistant to high temperature and high pressure on the injection end face of the injection punch (2), and control the thickness of the sprayed in-situ coating layer to be between 0.1 and 0.2 mm; close the pressure chamber (1), and the oily inert gas supply device starts to work. The oily inert gas flows through the blind holes of the injection piston rod (3) and the injection punch (2) to reach the middle parts of the heat-resistant sealing washer B (8) and the heat-resistant sealing washer A (7); (b) Open the vacuum port of the pressure chamber (1) and start vacuuming. The vacuum device can reduce the vacuum degree in the pressure chamber to below 5 kPa; after the vacuuming in the pressure chamber (1) is completed, close the pressure chamber vacuum port (120), and control the injection piston rod (3) to push back to drive the injection punch (2) to retract through the injection device controller (9). Open the pouring port (110) of the pressure chamber. Under the action of the pressure difference, the molten metal fills the pressure chamber (1); (c) While opening the pouring port (110) of the pressure chamber, the injection device controller (9) controls the split-flow cone (4) to retreat 10 - 20 mm and stop, and controls the injection piston rod (3) to drive the injection punch (2) to slowly advance to re-close the pouring port (110) and the vacuum port (120) of the pressure chamber. Then the split-flow cone (4) is fully opened, and the injection punch (2) quickly advances to the end face of the pressure chamber. When it is preset that the injection punch reaches the end face of the pressure chamber, the instantaneous pressure of the punch reaches between 100 and 200 Mpa to complete the injection; (d) After casting is completed, the injection punch (2) returns to the sealing position.

2. The high-vacuum pressure casting pressurization solidification method according to claim 1, characterized in that: In the injection device for horizontal high-vacuum pressure casting with pressure increase and solidification, radial blind holes A (210), radial blind holes B (220), radial blind holes C (230), and radial blind holes D (240) are symmetrically arranged on the lower and upper sides of the outer cylindrical surface of the injection punch; both the radial blind holes A (210) and the radial blind holes B (220) communicate with the axial blind hole E (260) inside the injection punch (2), and both the radial blind holes C (230) and the radial blind holes D (240) communicate with the axial blind hole F (250) inside the injection punch (2); the axial blind hole E (260) is further connected to the axial blind hole J (310) inside the injection piston rod (3), and the axial blind hole F (250) is further connected to the axial blind hole H (320) inside the injection piston rod (3); the ends of the axial blind hole J (310) and the axial blind hole H (320) are connected to the oily inert gas supply device.

3. The high-vacuum pressure casting pressurization and solidification method according to claim 1, characterized in that: In the injection device for horizontal high-vacuum pressure casting with pressure increase and solidification, the combined expansion ring A (5) and the combined expansion ring B (6) are respectively installed at both ends of the injection punch (2) and are flush with the end face of the injection punch (2); the heat-resistant sealing washer A (7) and the heat-resistant sealing washer B (8) are installed on both sides of the outer circumferential surface of the injection punch, and the distance from the end face of the injection punch is greater than 100 mm; the heat-resistant sealing washer A (7) and the heat-resistant sealing washer B (8) are made of materials resistant to high temperature and high pressure, and the outer ring radius expands by 0.1 - 0.3 mm after being heated.

4. The high-vacuum pressure casting pressurization solidification method according to claim 1, wherein: In the injection device of the horizontal high-vacuum pressure casting with pressure-boost solidification, the injection end face of the injection punch (2) is not a plane, and a grid-shaped groove is provided on the end face; the center distance between adjacent grid-shaped grooves is less than 2 - 10 mm, which is suitable for the relatively low-pressure environment in the pressure chamber, that is, the casting pressure is less than 100 Mpa; or, a plurality of circular concentric grooves are provided on the end face; the diameter difference between adjacent two circular concentric grooves is 2 - 10 mm; the width of the groove is 50 - 500 microns, and the depth of the groove is 10 - 100 microns, which is suitable for the relatively medium-pressure environment in the pressure chamber, that is, the casting pressure is between 100 - 150 Mpa; or, a spiral groove is provided on the end face; the center distance between adjacent two arcs of the spiral groove is less than 5 - 10 mm; the width of the spiral groove is 100 - 500 microns, and the depth of the groove is 10 - 100 microns, which is suitable for the high-pressure environment in the pressure chamber, that is, the casting pressure reaches 200 Mpa and above.

5. The high-vacuum pressure casting pressurization solidification method according to claim 1, characterized in that: In the injection device of the horizontal high-vacuum pressure casting with pressure-boost solidification, the cross-section of the flow splitter cone (4) is trapezoidal with a narrow upper part and a wide lower part, and the bottom angle is 45 - 60°.

6. The high-vacuum pressure casting pressurization and solidification method according to claim 1, characterized in that: In the oily inert gas, the oil is 10W - 40 SAE lubricating oil, and the inert gas is argon.

Images