Self-pressurization combined type precision forming die and forming machining method

Abstract

The invention relates to a self-pressurization combined type precision forming die and a forming machining method. The combined die comprises an outer die and an inner die. Wherein the outer die comprises an inner die cylinder and an outer die cylinder which are firmly combined through contact of conical surfaces, and a pressing assembly composed of an upper base plate, a lower base plate, a pressing plate and a heat insulation transition plate-heat insulation pad, and a pressing function and a self-pressurization foundation are achieved; a closed cavity defined by the side mold plates, the upper pressing head and the lower pressing head is a part needing to be pressed and formed, the outer walls of the side mold plates are combined into a cone and are in sliding fit with the surface of the inner wall of the mold cylinder of the outer mold through a conical surface, and an inner cavity of the inner mold corresponds to a workpiece in shape and size. The axial load is generated through vertical pressing of the pressing plate, the inner mold slides downwards along the conical surface to generate radial displacement so as to generate the radial load, the three-dimensional hydrostatic pressure formed in the blank exceeds the pressure applied by a single pressing plate, the self-pressurization effect is generated, and meanwhile three-dimensional precision forming and densification of the blank are achieved.

Description

Technical Field

[0001] The invention relates to the field of processing and forming of low-plasticity, difficult-to-form metal blocks or powders, and in particular to a self-pressurizing combined precision forming die and a forming processing method. Background Art

[0002] Molds are essential tools for the manufacturing and forming of all materials. They are also the manufacturing link with the highest technical content and the one that best reflects the manufacturing level. Although there are mold-free technical equipment such as cold isostatic pressing and hot isostatic pressing in powder forming of powder metallurgy manufacturing, the defects are still very obvious: poor forming accuracy, serious deformation, expensive equipment, and complex process routes, which affect the widespread promotion and application of this technology. In metal hot and cold forming, precision forming or near-net forming is often required. Under the premise of effectively improving performance, subsequent mechanical processing should be avoided or reduced as much as possible to save materials and working hours, thereby effectively reducing costs. For some low-plasticity metal materials, such as some magnesium alloys, aluminum alloys, and metal-based composite materials based on them, conventional pressure processing methods such as free forging and traditional die forging not only have a low yield, but also the shape and size of the forged parts are far from the final parts, requiring a large amount of subsequent machining, cutting off the most dense and best comprehensive performance forging surface, resulting in low performance of the surface and subsurface materials of the parts, low material utilization, and large waste.

[0003] For many low-plasticity materials, such as AZ80M and AZ91 D magnesium alloys, due to their low plasticity, surface microcracks and cracks are very likely to occur during conventional forging, and precision forming is almost impossible to achieve with ordinary forging. Plastic deformation processing of magnesium alloys is not only an important way to form, but also can produce a great strengthening and toughening effect, that is, the strength and plasticity after large plastic deformation are significantly improved.

[0004] In the current metal processing process, it is difficult to use the same power to achieve simultaneous processing in multiple directions.

[0005] On November 12, 2024, a search was conducted in the Chinese Patent Publication Database with "boost and die and radial and inner and outer and cone and processing and punch" as the abstract keywords, and the option of allowing synonym expansion was checked, but no relevant literature was found.

[0006] On November 12, 2024, an abstract search for “boost and die and radial and inner and outer and conical and processing and punch” was conducted on China National Knowledge Infrastructure, and no relevant literature was found.

[0007] On November 12, 2024, a search was conducted on the website of the United States Patent and Trademark Office for “Pressurization with mold with radial with innerwith outer with conical with machining with punch” and no relevant literature was found; the search URL was https: / / ppubs.uspto.gov / pubwebapp / .

[0008] On November 12, 2024, a search was conducted on the Korean Patent Office for “Pressurization and mold and radial and inner and outer and conical and machining and punch”, and no relevant literature was found; the search URL was http: / / eng.ki pr i s.or.kr / enghome / ma i n.jsp.

[0009] On November 12, 2024, a search was conducted on WIPO's https: / / patentscope2.wipo.i nt / for "Pressurization and mold and radial and inner and outer and conical and machining and punch", and no relevant literature was found.

[0010] On November 12, 2024, a search was conducted on the Japan Patent Office website https: / / www.jp latpat.i npit.go.jp / for "Pressurization and mold and radial and inner and outer and conical and machining and punch", but no relevant literature was found.

[0011] Completely different from the concept of this patent. Summary of the invention

[0012] Purpose of the invention: To provide a self-pressurizing combined precision molding die and processing method with better effect. The specific purpose can be seen in the multiple substantial technical effects of the specific implementation part.

[0013] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0014] The self-pressurized metal precision forming combined die is characterized by:

[0015] The combined mold includes an outer mold and an inner mold;

[0016] The outer mold includes: an inner mold cylinder 11 and an outer mold cylinder 12 which are firmly assembled by contacting with conical surfaces, and a pressing assembly composed of upper and lower pads, a pressing plate and a heat insulation transition plate-heat insulation pad, so as to realize the pressing molding function and the self-pressurization effect;

[0017] The inner mold includes a plurality of side mold plates, upper and lower pressing heads, a slider, a push punch and a push rod. The closed cavity surrounded by the plurality of side mold plates and the upper and lower pressing heads is the workpiece to be pressed and formed. The shape and size of the inner mold and the workpiece are strictly corresponding.

[0018] The outer mold and the inner mold are in sliding contact through the conical surface. The pressure plate in the outer mold is in vertical contact with the pressure head of the inner mold. When the press machine is pressed down, its platen drives the pressure plate and the pressure head to achieve vertical (i.e. axial) pressing displacement. When the mold is closed, the pressure plate pushes the inner mold including the side mold plate to undergo vertical displacement, and the compression displacement along the radial direction of the cone is generated due to the vertical sliding of the inner mold downward along the conical surface. The value of the radial compression displacement (ΔR) is equal to the tangent value of the vertical displacement (ΔH) ( See Fig.25 Where φ is the cone angle of the inner wall of the inner die cylinder; correspondingly, the pressing force P of the press machine causes the side template to slide along the conical surface. The pressing force is decomposed into the friction component F along the conical surface and the oblique radial pressure p applied to the blank through the side template. Combined with the hydrostatic pressure generated by the vertical pressure of the pressure plate, the radial and axial pressures on the blank far exceed the vertical pressure applied by a single pressure plate, producing a self-pressurization effect, while achieving three-dimensional precision forming and densification of the blank; this multi-directional pressure method results in the absence of tensile stress at any position in the blank, which can avoid cracking and local damage to the workpiece.

[0019] A further technical solution of the present invention is that the inner mold cylinder 11, the upper pressure head 14, the lower pressure head 21, the mold side plate 13, the ejector rod, the lateral slide block, and the ejection punch of the self-pressurizing combined precision molding mold are made of hot working die steel or heat-resistant ultra-high strength steel;

[0020] The lower pressing plate 6, the upper pressing plate 7 and the outer die cylinder 12 are made of ultra-high strength steel or ordinary heat-resistant steel;

[0021] The pad and the intermediate pad are made of ordinary low alloy steel or high strength steel;

[0022] The thermal insulation pad is made of high thermal resistance materials or inorganic non-metallic materials such as graphite;

[0023] The inner mold system, including side mold plates, upper and lower pressure heads, ejection slides, punches and ejector pins, is designed and manufactured according to the adaptability of the shape, size and material of the specific parts.

[0024] A further technical solution of the present invention is that the mold cylinder is formed by nesting an outer mold cylinder and an inner mold cylinder, and the nesting surfaces of the outer mold cylinder and the inner mold cylinder are conical surfaces: the external surface of the outer mold cylinder is a right circular cylinder, and the inner surface is a right conical surface, that is, it is small at the top and large at the bottom, and can achieve continuous self-tightening without loosening during work; the inner and outer surfaces of the inner mold cylinder are both conical surfaces, and its outer surface is a right cone, that is, it is small at the top and large at the bottom, and its taper angle is the same as the taper angle of the inner surface of the outer mold cylinder, and the specific taper angle is between 12 and 15.5°, and it is in contact with the inner surface of the outer mold cylinder; the inner surface of the inner mold cylinder is a negative conical surface that is large at the top and small at the bottom, and the specific taper angle is between 25 and 40°.

[0025] A further technical solution of the present invention is that what contacts the inner conical surface of the inner mold cylinder of the conical combination mold cylinder is a precision-molded combined inner mold module, which is composed of 2 to 6 side mold plates, and the inner sides of the side mold plates facing the axial direction are assembled to form the outer contour of the component to be pressed; the outer surface of the side mold plate is a conical surface, and its cone angle is the same as the cone angle of the inner surface of the inner mold cylinder, and they are in contact with each other in a sliding friction fit manner; the inner mold combination composed of the combined assembly of all side mold plates and the upper and lower pressure heads completely defines the entire shape and size of the component to be pressed.

[0026] A further technical solution of the present invention is that a push rod-slider-pushing punch is set up, which pushes the lateral slider downward by pressing the push rod, generates lateral or radial pushing force with the help of the conical surface, and pushes the lateral pushing punch to realize the forming of local lateral grooves, holes and other structural shapes.

[0027] A further technical solution of the present invention is that the 2 to 6 side templates of the combined inner mold module are assembled into a complete cone along the circumferential direction, and a compressible insert made of soft material is inserted between each side template and the adjacent side template. The insert is inserted when the mold is assembled, and its length, that is, the dimension along the axial direction of the cone of the inner mold cylinder, is adapted to the height of the side template, its thickness, that is, the radial dimension along the cone of the inner mold cylinder, is adapted to the thickness of the edge of the side template in the circumferential direction, and its width, that is, the tangential dimension along the circumferential direction of the cone of the inner mold cylinder, is adapted to its thickness. The inserts may be made of lead, zinc, rubber or plastic, suitable for pressing and forming at relatively low temperatures, such as below 200°C; soft metal industrial pure aluminum or magnesium, suitable for pressing and forming at medium temperatures, such as 200-600°C; soft industrial pure iron, suitable for pressing and forming at relatively high temperatures, such as 500-850°C, to ensure that when the assembled combined inner mold is pressed downward to produce a vertical displacement along the axis of the cone, a sufficiently large radial compression deformation can occur, and no excessive resistance is generated to hinder the radial displacement of the side mold plate.

[0028] A further technical solution of the present invention is that the inner cavity space formed by the upper and lower pressing heads and the side template is the entire outer contour of the part to be pressed, wherein the lower surface of the upper pressing head and the upper surface of the lower pressing head are the upper and lower contour surfaces of the part to be pressed, and the surface can be a regular rotation surface, or a symmetrical or asymmetrical concave and convex curved surface or plane.

[0029] A self-pressurizing combined precision molding die and molding processing method, characterized in that the inner mold module realizes radial displacement during the pressing process of a press machine: lateral compression molding is produced by the radial displacement of the side mold plate, thereby realizing three-dimensional precision molding pressing; the precision molding die can be provided with multiple (>=0) ejector rods and a top-entry lateral punch system to realize local lateral molding.

[0030] A further technical solution of the present invention is to use any one of claims 1 to 7, a self-pressurizing combined precision molding die;

[0031] Workflow: Preheat separately--》Mold installation--》Place blank--》Pre-press--》Press and push in the ejector--》Press the inner mold as a whole--》Complete pressing through displacement control--》Mold stripping cylinder--》Take out the pressed parts.

[0032] A further technical solution of the present invention is:

[0033] Detailed description of the workflow:

[0034] (10) Apply a release agent on the working surface or contact surface of the main mold. The release agent is a paste-like lubricant with good adhesion, such as a graphite + butter mixture;

[0035] (11) Install the upper and lower insulation transition plates, insulation pads, pads, and pressure plates; the upper and lower insulation transition plates are fastened to the press platen through the mounting holes around the plates with T-bolts or special bolts matching the press, and the upper plates are hoisted through the upper pressure head pull rod; the plates other than the lower pressure plate at the lower part are positioned through the edge boss of the pressure plate and placed in order;

[0036] (12) Place the upper and lower pressing heads and all side mold plates in a heating furnace for preheating, and set the temperature to T3; place the inner and outer mold cylinders and the upper and lower pressing plates in another heating furnace, and set the temperature to T4; if the material to be formed is AZ80M magnesium alloy, then T3 = 250 ~ 300 ° C, T4 = 200 ~ 250 ° C; if the material to be formed is aluminum, magnesium or other metal or alloy powder or metal matrix composite material powder, then T3 = 300 ~ 360 ° C, T4 = 200 ~ 250 ° C;

[0037] (13) Preheat the blank. The blank can be in block or powder form. Set the temperature to T1, and T1 is the appropriate temperature for forming the blank. If it is powder, preheat the powder at temperature T2 under anti-oxidation and sealing conditions, and T2 < T1. For example, for an AZ80M magnesium alloy ingot, place the accurately cut magnesium alloy block after homogenization annealing in a furnace with a protective atmosphere, where T1 = 320 - 430 °C. If the material to be formed is an aluminum matrix composite: 10 - 25% vol silicon carbide powder-reinforced aluminum alloy, such as the powder of 2000 series aluminum alloy, accurately weigh the powder, put it into a thin-walled iron cylinder, seal it with a lid, and place it in a furnace with a protective atmosphere, then T2 = 320 - 460 °C. The preheating time should not exceed the specified value. For example, for AZ80M magnesium alloy, the holding time after being heated through should not exceed 4 hours; for metal powder or metal matrix composite powder, the holding time should not exceed 2 hours.

[0038] (14) Assemble the inner and outer die cylinders into one body; install the slider, the pushing punch, and the ejector rod into the corresponding holes in the side template.

[0039] (15) Install the first-round die assembly in the order of the lower platen 6, the lower punch 21, the temporary spacer block 88, the combined die cylinders 11, 12, the combined die side plates 13, the upper punch 14, the lateral pushing 1 - 1st slideway and the slider 15, the lateral pushing die 1 - 1st punch 16, the lateral pushing 1 - 2nd slider 17, the lateral pushing die 1 - 2nd punch 18, the lateral pushing 2 - 1st slider 19, the lateral pushing die 2 - 1st punch 20. Then insert the pre-prepared inserts 29 at each side template gap to keep the side templates at equal intervals; place the preheated block blank into the cavity surrounded by the side templates; place the upper punch 14 on the blank block and fasten the upper platen 7; turn on the heating rod (22) for die cylinder preheating and adjust the temperature control range to <= 300 °C.

[0040] If it is powder forming, it is required that the inserts are in close contact with the side templates, and adjust the vertical position of the lower punch to make the gap with the side template as small as possible. Also, inserts can be placed between the side template 13 and the lower punch 21 to block the gap so that the powder does not leak. Pour the preheated powder into the die cavity, and allow the die cylinder to be gently tapped to make the powder as dense as possible. Mechanical vibration can also be used to densify the powder.

[0041] (16) Start the press, lower the upper platen to pre-press. When the load indication of the press starts to rise significantly, stop applying pressure, raise the punch to separate the upper platen 7 from the upper 2nd spacer block 8; remove the temporary spacer block 88 and check the alignment of the entire set of die components - it is required that the center lines of all the platens, spacer blocks, platens, and punches between the upper and lower platens of the press are near the center of the press platen, and the accuracy should be better than 10 mm.

[0042] If it is powder molding, after the filled powder fills the mold cavity completely, place the upper pressure head 14 and the upper pressure plate 7, start the press, slowly press down to about 1 / 2 of the set pressure, keep the pressure unchanged for about 5 to 30 minutes, remove the pressure, raise the press plate, remove the upper pressure plate 7 and the upper pressure head 14, continue to fill the powder until the mold cavity is filled, repeat the placement of the upper pressure head 14, the upper pressure plate 7, and apply pressure until the quantitatively weighed powder is completely filled into the mold cavity, and finally slowly press to the maximum pressure, keep for about 30 minutes, and then wait for the mold barrel to be heated to T5 by the preheating heating rod 22, T5 is the lowest hot pressing temperature set for the metal matrix composite material, and press again to the pre-set hot pressing load or blank pressure;

[0043] (17) Depressurize, remove all temporary pads 88, and check the centering status of the mold; apply pressure at a pre-set pressure speed until it is close to more than 90% of the vertical displacement of the final molding displacement, depressurize again, raise the press platen, remove the upper pressing plate 7, place the pressing ring 71, make the pressing ring contact with all the ejector pins, then place the upper pressing plate, and then slowly lower the platen to ensure that it is centered and slowly apply pressure until the pressing ring 71 and the upper pressing plate 7 are in full contact, then increase the pressure speed until the pressure reaches the set displacement to complete the precision pressing molding; note that the excess part of the calculated quantitative blank / powder will be squeezed out from the gap between the lower pressing head and the material withdrawal groove of the side template to form burrs;

[0044] (18) Demolding: gradually turn off the heating rod 22, raise the press platen, remove the upper press plate 7, remove the press ring, use the lifting ring 23 set on the upper edge of the mold barrel, and use the upward movement of the press platen to lift the entire mold assembly, i.e., the inner and outer mold barrels + side mold plates +

[0045] Upper and lower rams, insert 2-3 temporary pads 88 between the lower ram 21 and the lower platen 6, evenly distribute them, ensure alignment, lower the press platen, insert 2-3 temporary pads 88 on the upper edge of the mold barrel, cover the demoulding platen on the upper edge of the inner mold barrel, place the upper platen 7 on the upper part of the demoulding platen, start the press, slowly press down to achieve demoulding - that is, push the inner mold out of the mold barrel, remove the upper ram, side mold plate, ejector rod, slider and ejection punch, and finally remove the lower ram, take out the pressed parts, place them in a heat preservation furnace of ~200℃, or bury them in a dry sand box, cool them to <200℃, take them out, cool them to room temperature in the air, deburr, polish them, and send them for inspection;

[0046] Clean the mold, reapply release agent, preheat separately, and repeat the process to complete the press molding of the next part.

[0047] The present invention adopting the above technical solution has the following beneficial effects compared with the prior art: the mold system and molding method of the present invention can realize high-precision high-performance magnesium alloy, aluminum alloy and metal powder or metal matrix composite powder molding products. The successful development and production of a variety of low-plasticity, difficult-to-form bulk metal materials or metal powder, metal matrix composite powder made of complex parts constitute the core elements of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to further illustrate the present invention, the following is further described in conjunction with the accompanying drawings:

[0049] Figure 1 Schematic diagram of mold assembly;

[0050] 1. Lower platen of press (with grooves and holes for positioning and fastening), 2. Insulation pad, 3. Lower insulation transition plate, 4. Insulation gasket, 5. Lower No. 2 pad, 6. Lower pressure plate, 7. Upper pressure plate, 8. Upper No. 2 pad, 9. Upper middle pad, 10. Upper platen of press (with grooves and holes for positioning and fastening), 11. Inner mold cylinder, 12. Outer mold cylinder, 13. Mold side plate, 14. Upper Pressure head, 15, side-to-side push-in slider No. 1-1, 16, side-to-side push-in die punch No. 1-1, 17, side-to-side push-in slider No. 1-2, 18, side-to-side push-in die punch No. 1-2, 19, side-to-side push-in slider No. 2-1, 20, side-to-side push-in die punch No. 2-1, 21, lower pressure head, 69, ejector No. 1, 70, ejector No. 2, 71, pressure ring (thickness is adapted to the upper pressure plate, see Figure 1 , inner diameter D 环内径 =D 上压板座直径 +2mm, outer diameter D 环外径 =D 外模筒外径 88. Temporary spacers (4 or 6 parallelepiped high-strength steel blocks of equal size, such as 50X50X50mm);

[0051] Figure 2 It is a schematic diagram of a nested mold cylinder;

[0052] 11 is an inner mold cylinder, 12 is an outer mold cylinder, 13 is a mold side plate, 22 is a heating rod, and 23 is a lifting ring;

[0053] Figure 3 For the outer mold cylinder;

[0054] 12 is the outer mold cylinder, 24, the inner side of the outer mold cylinder matches the conical surface (cone angle α1 = 12 ~ 17.5°)

[0055] Figure 4 For the inner mold cylinder;

[0056] 11. Inner mold cylinder, 25. Outer cone surface matching with the inner side of the mold cylinder (cone angle α2=α1), 26. The inner side of the inner mold cylinder matches the cone surface of the side mold plate (β1=25-40°);

[0057] Figure 5 Side formwork (combined state, 2 to 6 pieces in total);

[0058] 13-1, side template No. 1, 13-2, side template No. 2, 27, side template outer side matching cone (β2 = β1), 28, side template large gap, 29, insert (side template gap joint), 30, No. 1 side punch slide, 31, No. 2 side punch slide, 32, No. 3 side punch slide, 66, ejector hole

[0059] Figure 6 It is the cross-section of the right side template;

[0060] 61. Side template working surface (inner surface, may be concave and convex), 62. Ejector pin socket, 63. Side punch slider cavity, 64. Side punch slideway, 65. Side template outer wall (adapted to the conical surface of the inner wall of the inner die cylinder, sliding fit, lubrication);

[0061] Figure 7 is the top rod (total number >= 0);

[0062] 67, top bar No. 1, 68, top bar No. 2;

[0063] Figure 8 Schematic diagram of the side-entry punch and slider (total number >= 0 sets);

[0064] 33, No. 1 side-entry punch, 34, No. 1 side-entry punch slider, 35, No. 2 side-entry punch, 36, No. 2 side-entry punch slider, 37, No. 3 side-entry punch, 38, No. 3 side-entry punch slider, 39, circumscribed conical surface (sliding fit, lubrication) (β2 = β1)

[0065] Fig. 9 It is a three-dimensional schematic diagram of the lateral ejection slider and the punch (No. 1 lateral punch, No. 2 lateral punch, No. 3 lateral punch, all lateral punches have similar structures but different sizes); 72, circumscribed conical surface (the taper is the same as the outer surface of the side template, sliding fit, lubrication), 73, upper surface of the slider (contact surface with the ejector rod), 74, centripetal surface (contact with the end face of the ejection punch, sliding fit, lubrication), 75, rear end face of the ejection punch (contact with the centripetal surface of the slider, sliding fit, lubrication), 76, ejection punch;

[0066] Fig.10 A press head is provided for the mold;

[0067] 40, outer cylindrical surface of the pressing head, 41, central positioning hole of the pressing head, 42, forming convex column of the pressing head;

[0068] Fig.11 It is the die pressing head;

[0069] 43. a cylinder for the lower pressure head seat, 44. a convex cylinder for forming the lower pressure head, 45. a positioning pin hole;

[0070] Fig.12 The assembly relationship between the upper insulation transition plate and the insulation pad;

[0071] 51. The mounting hole for the press base, 52. The mounting center hole for the upper press head tie rod;

[0072] Fig.13 It is the assembly relationship of the upper pressure head;

[0073] 2. Insulation pad, 4. Insulation gasket, 7. Upper pressing plate, 8. Upper No. 2 pad, 9. Upper middle pad, 10. Upper platen of press (with slots and holes for positioning and fastening), 46. Tie rod;

[0074] Fig.14 The upper middle pad;

[0075] 3-1, middle plate of upper pressure head, 53, concave platform on the middle plate of upper pressure head, 54, concave platform on the middle plate of upper pressure head, 55, center tie rod hole of upper pressure head;

[0076] Fig.15 It is the upper No. 2 pad;

[0077] 51. Tie rod mounting hole;

[0078] Fig.16 For the pressure ring and the upper pressure plate;

[0079] 7 is an upper pressing plate, 71 is a pressing ring, 89 is a lifting hole;

[0080] Fig.17 It is the upper pressure head pull rod;

[0081] 47, the middle rod portion of the short tie rod, 48, the truncated cone at the lower end portion of the tie rod, 49, the middle rod portion of the long tie rod, 50, the threaded section at the upper end of the tie rod;

[0082] Fig.18 It is a schematic diagram of the combined type and assembly relationship of the lower pressure head;

[0083] Fig.19 It is a combination of a lower insulation transition plate and an insulation pad;

[0084] 56. Center positioning hole of thermal insulation pad, 57. Center positioning hole of lower thermal insulation transition plate

[0085] Fig. 20 For the bottom plate;

[0086] 3-2, lower pad, 58, pad center positioning hole;

[0087] Fig.21 For the lower pressure plate;

[0088] 6 is a lower pressing plate, 59 is a lower pressing plate boss, 60 is a lower pressing plate positioning hole;

[0089] Fig. 22 For demoulding press plate;

[0090] 89 is a lifting hole (M10-25), 90 is a demoulding platen (diameter ≈ outer diameter of outer mold cylinder, thickness approximately equal to thickness of upper platen), 91 is a center positioning hole;

[0091] Fig.23 Schematic diagram of complex structural parts of hot-compressed magnesium alloy, aluminum alloy or metal matrix composite materials (die core: 2 to 6 side mold plates, upper and lower pressure heads, multiple sets (>=0) of sliders + ejector punches + ejector rods + pressure rings);

[0092] 77 is a hard-to-deform magnesium alloy precision pressed part (magnesium alloy, aluminum alloy, zinc alloy or metal matrix composite material and other metal material parts), 78, No. 2 side top-entry type formed inner concave hole, 79, No. 1 side top-entry type formed inner concave hole, 80, top top-entry type formed concave hole, 81, cross section, 82, No. 3 side top-entry type formed inner concave hole, 83, bottom hole structure with a downward pressure head top-entry type formed;

[0093] Fig.24 Preparation of asymmetric hollow parts of metal matrix composites by powder metallurgy;

[0094] 84. Lower curved ring surface (upper and lower pressure head parting surface), 85. Side wall lateral hole (formed by fixed or removable lateral mandrel, 86. Asymmetric hollow part of metal matrix composite material, 87. Upper curved ring surface (optional upper and lower pressure head parting surface);

[0095] Fig.25 Schematic diagram of displacement and load analysis. DETAILED DESCRIPTION

[0096] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the following specific embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. In the description of the present invention, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", "top", "bottom", etc. is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal connection of two elements. In addition, the cone angle data in the design of the present invention is only a preferred data combination, not a limitation of the present invention. In the neighborhood of these data, the precision molding function of the present invention can also be realized, all of which belong to the protection scope of the present invention. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood in specific circumstances.

[0097] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0098] This patent provides a variety of parallel solutions. The different expressions are improved solutions or parallel solutions based on the basic solution. Each solution has its own unique characteristics. In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other. The fixing method not described in the text can be any fixing method such as thread fixing, pin fixing or glue bonding.

[0099] A self-pressurizing combined precision molding die can realize one-time precision molding of metal blocks or metal powder materials, characterized in that the mold system is composed of a precision molding combined inner and outer mold cylinders of a conical cylinder combination outer mold, an upper and lower pressing plate and a pressing head with a conical surface; the inner mold module realizes radial displacement during the pressing process of the press: the lateral compression molding is produced by the radial displacement of 2-6 side mold plates in the inner mold module, thereby realizing three-dimensional precision molding and pressing; the precision molding die can be provided with multiple ejector rods and top-entry side punch systems to realize local lateral molding; the number of ejector rods and top-entry side punch systems depends only on the molding needs. On each side mold plate, there may be no ejector rod and top-entry side punch system, or more than one set of ejector rods and top-entry side punch systems may be provided. The mold system uses components made of more than three materials: the inner mold barrel, upper and lower pressure heads, side mold plates, ejector pins, lateral sliders, and ejector punch systems of the self-pressurized combined precision molding mold are made of hot-working mold steel or other heat-resistant ultra-high strength steels, titanium alloys, and high-temperature alloys; the upper and lower pressure plates and the outer mold barrel are made of conventional ultra-high strength steel or heat-resistant steel; the pads and the middle pads are made of ordinary low-alloy steel or heat-resistant steel, high-strength steel; and the thermal insulation pads are made of high thermal resistance materials or other inorganic non-metallic materials. The outer mold system, including the pressure plate, the pad, and the thermal insulation transition plate, is a universal setting that can be applied to the molding of multiple parts of different shapes and similar sizes; the inner mold system, including the side mold plates and the upper and lower pressure heads, the ejector sliders, the punches, and the ejector pins, is adaptively and specifically designed according to the shape, size, and material of the specific components. These changes still belong to the content of the present invention and do not vary with the changes in the inner mold system.

[0100] By using the mold system and molding method of the present invention, high-precision and high-performance products made of magnesium alloy, aluminum alloy, zinc alloy, etc. have been realized. A variety of complex parts made of difficult-to-form metal materials have been successfully developed and produced, which constitute the core elements of the present invention.

[0101] A self-pressurizing combined precision molding mold consists of an outer mold and an inner mold, wherein the outer mold includes: inner and outer mold cylinders that are firmly combined by contacting with conical surfaces, and a pressing assembly composed of upper and lower pads, a pressing plate, and an insulating transition plate-insulating pad to achieve a pressing function and a self-pressurizing basis; wherein the inner mold includes 2-6 side mold plates and upper and lower pressure heads, a slider-pushing punch and a push rod, wherein the closed cavity surrounded by the side mold plates and the upper and lower pressure heads is the component to be pressed and formed, and the shape and size of the inner mold and the workpiece are strictly corresponding.

[0102] The outer mold and the inner mold are in side sliding contact through the conical surface, and the pressure plate in the outer mold is in vertical contact with the pressure head of the inner mold. When the press is pressed down, the pressure plate pushes the pressure head to achieve vertical pressing displacement. When the mold is closed, the pressure plate pushes the side mold of the inner mold downward to cause vertical displacement and generate radial compression displacement pointing to the axis of the cone. The value of the radial displacement (ΔR) is equal to the tangent value of the vertical displacement (ΔH) ( Where φ is the cone angle of the inner wall of the inner die cylinder). Correspondingly, the oblique radial pressure p applied to the blank by the outer cone surface of the vertical side die plate generated by the pressing force P of the press is: Combined with the hydrostatic pressure generated by the vertical pressure of the pressing plate, the radial and axial pressure on the blank can exceed the pressure applied by a single pressing plate, resulting in a self-pressurization effect, while achieving three-dimensional precision forming and densification of the blank. This multi-directional pressure method results in no tensile stress at any position in the blank, thus avoiding cracking and local damage, and achieving high yield and high-quality, high-efficiency, low-cost manufacturing.

[0103] A self-pressurizing combined precision molding die can realize one-time precision molding of bulk metal or powdered metal materials, characterized in that the die system is composed of a conical inner and outer cylinder combined outer mold cylinder, a conical surface matched precision molding combined inner mold module side mold plate, upper and lower pressing plates and a pressing head; the side mold plate realizes radial displacement during the pressing process of the press; the radial displacement of the side mold plate produces lateral compression molding, thereby realizing three-dimensional precision molding pressing; the precision molding die can be provided with multiple ejector rods and a top-entry side punch system , local lateral forming can be achieved; the mold system uses components made of more than three materials: the inner mold barrel, upper and lower pressure heads, side mold plates, ejector rods, lateral sliders, and ejector punches of the self-pressurized combined precision molding mold are made of hot-working mold steel or other heat-resistant ultra-high strength steels, titanium alloys, and high-temperature alloys; the upper and lower pressure plates and the outer mold barrel are made of conventional ultra-high strength steel or ordinary heat-resistant steel; the pads and the middle pads are made of ordinary low-alloy steel or high-strength steel, heat-resistant steel; the thermal insulation pads are made of high thermal resistance materials or other inorganic non-metallic materials. Among them, the outer mold system, including the pressure plate, pad, thermal insulation transition plate, and thermal insulation pad are universal settings; the inner mold system, including the side mold plates and upper and lower pressure heads, ejector sliders, punches, and ejector rods, can be adaptively designed and changed according to the shape, size, and material of the specific components. These changes still belong to the content of the present invention and do not change with the changes in the inner mold system.

[0104] A self-pressurizing combined precision molding mold, wherein the mold barrel is formed by nesting an outer mold barrel and an inner mold barrel, and the nesting surface is a conical surface: the outer surface of the outer mold barrel is a right circular cylinder, and the inner surface is a right conical surface, that is, it is small at the top and large at the bottom, and can achieve continuous self-tightening without loosening during work; the inner and outer surfaces of the inner mold barrel are both conical surfaces, and the outer surface is a right cone, that is, it is small at the top and large at the bottom, and its taper angle is the same as the taper angle of the inner surface of the outer mold barrel, and the specific taper angle is between 12 and 17.5°, and it is in contact with the inner surface of the outer mold barrel; the inner surface of the inner mold barrel is a conical surface that is large at the top and small at the bottom, and the specific taper angle is between 25 and 40°.

[0105] A self-pressurizing combined precision molding mold, wherein the module in contact with the inner conical surface of the inner mold barrel of the conical combined mold barrel is a precision molding combined inner mold module, which is composed of 2 to 6 side mold plates, and the inner side of the side mold plates (towards the axial direction) is assembled into the outer contour of the part to be pressed; the outer surface of the side mold plate is a conical surface, and its cone angle is the same as the cone angle of the inner surface of the inner mold barrel, and they are in contact with each other in a sliding friction fit manner; the inner mold combination composed of all the side mold plates and the upper and lower pressure heads assembled together completely defines the entire shape and size of the part to be pressed.

[0106] The self-pressurized combined precision forming mold system has a push rod-slider-pushing punch, which pushes the lateral slider downward by pressing the push rod, generates lateral (radial) pushing force with the help of the conical surface, and pushes the lateral pushing punch to realize the forming of local lateral grooves, holes and other structural shapes.

[0107] The 2 to 6 side molds of the combined inner mold module are assembled along the circumferential direction to form a complete cone. A compressible insert made of soft material is inserted between each side mold and the adjacent side mold. The insert is inserted when the mold is assembled. Its length (dimension along the axis direction of the cone of the inner mold cylinder) is adapted to the height of the side mold, its thickness (dimension along the radial direction of the cone of the inner mold cylinder) is adapted to the thickness of the edge of the side mold in the circumferential direction, and its width (dimension along the circumferential direction of the cone of the inner mold cylinder, i.e., the tangential direction) is adapted to its thickness. The material of the insert can be lead, zinc, rubber or plastic (when pressed and formed at a lower temperature, such as below 200°C), soft metal industrial pure aluminum or magnesium (when pressed and formed at a medium temperature, such as 200-600°C), soft industrial pure iron (when pressed and formed at a higher temperature, such as 500-850°C), so as to ensure that the assembled combined inner mold described in claim 4 can undergo sufficiently large radial compression deformation when it is pressed downward along the axis of the cone, and does not produce excessive resistance to hinder the radial displacement of the side mold.

[0108] The inner cavity space formed by the upper and lower pressing heads and the side templates is the entire outer contour of the part to be pressed, wherein the lower surface of the upper pressing head and the upper surface of the lower pressing head are the upper and lower contour surfaces of the part to be pressed, and the surfaces can be regular rotation surfaces or symmetrical or asymmetrical concave and convex curved surfaces;

[0109] The inner cavity formed by the inner mold combination is the side profile of the part to be pressed. The inner surface shape of each side mold plate, including the surface convexity and concave-convexity and lateral slide holes, has its shape, size and position determined by the design drawing of the part to be pressed. After the inner mold combination completes the pressing, it becomes the final part.

[0110] Embodiment 1:

[0111] Precision pressing of asymmetric complex structural parts of low-plasticity and difficult-to-deform magnesium alloys:

[0112] Schematic diagram as Fig.23 As shown. For some low-melting-point metal materials such as magnesium alloys, aluminum alloys, zinc alloys, etc. with low plasticity, Figure 5 The inner mold system shown, including side mold plates, upper and lower pressure heads, lateral ejection slides and punches, can achieve hot precision forming.

[0113] Embodiment 2:

[0114] Schematic diagram as Fig.24 As shown. Preparation and precision molding of complex structure metal matrix composite parts by powder metallurgy. By using the outer mold system of the present invention and adaptively changing the inner mold, the following annular, asymmetric, and complex structure metal matrix composite parts can be produced. The required changes to the inner mold are: (1) Each of the two side molds is provided with a platform-type hole opening pattern; (2) The upper and lower punches are arranged to form an inner core structure, and a docking structure is arranged between the lower punch and the lower curved annular surface of the component, such as a material withdrawal gap in the internal cavity of the lower punch, so as to achieve vertical precision size assurance; (3) The ejector rod-slider-pushing punch structure is omitted, and the lateral hole is realized by a lateral core rod completely fixed on the side mold. The lateral core rod and the side mold can also be designed as two independent, assemblable parts to reduce mold material waste and save costs.

[0115] Innovatively, each of the above effects exists independently, and a set of structures can be used to combine the above results.

[0116] It should be noted that the multiple solutions provided by this patent include the basic solution itself, which are independent of each other and do not restrict each other, but they can also be combined with each other without conflict to achieve multiple effects together.

[0117] The basic principle, main features and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the protection required.

Claims

1. Self-pressurized metal precision forming combined mold, characterized in that: The combined mold includes an outer mold and an inner mold; The outer mold comprises: an inner mold cylinder (11) and an outer mold cylinder (12) which are firmly assembled by contacting with conical surfaces, and a pressing assembly composed of upper and lower pads, a pressing plate and a heat insulation transition plate-heat insulation pad, which realizes the vertical pressing function and the self-pressurization foundation; The inner mold includes a plurality of side molds, upper and lower pressing heads, a slider, a push punch and a push rod. The closed cavity surrounded by the plurality of side molds and the upper and lower pressing heads is the part to be pressed and formed. The shape and size of the inner mold cavity and the part are strictly corresponding. The outer mold and the inner mold are in side sliding contact through the conical surface, and the pressure plate in the outer mold is in vertical plane contact with the pressure head of the inner mold; when the press is pressed down, the pressure plate pushes the pressing assembly to achieve vertical pressing displacement to achieve mold closing. When the mold closing is completed, the pressure plate pushes the side template of the inner mold downward to achieve vertical displacement and produce radial compression displacement of the cone. The value of the radial compression displacement (ΔR) is equal to the tangent value of the vertical displacement (ΔH). Where φ is the cone angle of the inner wall of the inner die cylinder; correspondingly, the oblique radial pressure p applied to the blank by the outer cone surface of the vertical side die generated by the pressing force P of the press is: Combined with the hydrostatic pressure generated by the vertical pressure of the pressure plate, the radial and axial pressures applied to the blank can far exceed the vertical pressure applied by a single pressure plate, producing a self-pressurization effect, while achieving three-dimensional precision forming and densification of the blank; this multi-directional pressure method results in the absence of tensile stress at any position in the blank, which can avoid cracking and local damage on the workpiece surface.

2. The self-pressurizing metal precision forming combined mold according to claim 1, characterized in that: The inner mold cylinder (11), the upper pressure head (14), the lower pressure head (21), the mold side plate (13), the ejector rod, the lateral slide block, and the ejection punch of the self-pressurizing combined precision molding mold are made of hot-working mold steel or heat-resistant ultra-high strength steel; The lower pressing plate (6), the upper pressing plate (7) and the outer mold cylinder (12) are made of ultra-high strength steel or ordinary heat-resistant steel; The pad and the intermediate pad are made of ordinary low alloy steel or high strength steel; The thermal insulation pad is made of high thermal resistance material or inorganic non-metallic material; The inner mold system, including the side mold plates and the upper and lower pressing heads, the ejection slide, the punch and the ejector pin, is designed and manufactured according to the adaptability of the shape, size and material of the specific object parts.

3. The self-pressurizing metal precision forming combined die according to claim 1, characterized in that: The mold cylinder is formed by the nesting of an outer mold cylinder and an inner mold cylinder, and the nesting surfaces of the outer mold cylinder and the inner mold cylinder are conical surfaces: the external surface of the outer mold cylinder is a right circular cylinder, and the internal surface is a right conical surface, that is, it is small at the top and large at the bottom, and can achieve continuous self-tightening without loosening during work; the inner and outer surfaces of the inner mold cylinder are both conical surfaces, and its outer surface is a right cone, that is, it is small at the top and large at the bottom, and its taper angle is the same as the taper angle of the inner surface of the outer mold cylinder, and the specific taper angle is between 12 and 17.5°, and it is in contact with the inner surface of the outer mold cylinder; the inner surface of the inner mold cylinder is a negative conical surface that is large at the top and small at the bottom, and the specific taper angle is between 25 and 40°.

4. The self-pressurizing metal precision forming combined die according to claim 1, characterized in that: In contact with the inner conical surface of the inner mold barrel of the conical combination mold barrel is a precision-molded combined inner mold module, which is composed of 2 to 6 side mold plates, and the inner sides of the side mold plates facing the axial direction are assembled to form the outer contour of the component to be pressed; the outer surface assembled by the side mold plates is a conical surface, and its cone angle is the same as the cone angle of the inner surface of the inner mold barrel, and they are in contact with each other in a sliding friction fit manner; the inner cavity formed by the inner mold combination composed of all side mold plates and the upper and lower pressure heads completely defines the entire shape and size of the component to be pressed.

5. The self-pressurizing metal precision forming combined die according to claim 1, characterized in that: A push rod, a slider and a push punch can be arranged in the side template. By pressing the push rod downward, the lateral slider is pushed downward, and a lateral or radial push force is generated with the help of the conical surface, and the lateral push punch is pushed to realize the forming of local lateral grooves, holes and other internal structural shapes.

6. The self-pressurizing metal precision forming combined die according to claim 1, characterized in that: The 2 to 6 side templates of the combined inner mold module are assembled into a complete cone along the circumferential direction. A compressible insert made of soft material is inserted between each side template and the adjacent side template. The insert is inserted when the mold is assembled. Its length, that is, the dimension along the axis direction of the inner mold cylinder cone, is adapted to the height of the side template. Its thickness, that is, the radial dimension along the inner mold cylinder cone, is adapted to the edge thickness of the side template in the circumferential direction. Its width, that is, the tangential dimension along the circumferential direction of the inner mold cylinder cone, is adapted to its thickness. The insert can be made of lead, zinc, rubber or plastic, which is suitable for pressing and molding at a relatively low temperature, such as below 200°C; soft metal industrial pure aluminum or magnesium, which is suitable for pressing and molding at a medium temperature, such as 250 to 600°C; soft industrial pure iron, which is suitable for pressing and molding at a relatively high temperature, such as 500 to 850°C, to ensure that the assembled combined inner mold can undergo sufficiently large radial compression deformation when it is pressed down to produce a downward displacement along the axis of the cone, and does not produce excessive resistance to hinder the radial displacement of the side template.

7. The self-pressurizing metal precision forming combined die according to claim 1, characterized in that: The inner cavity space formed by the upper and lower pressing heads and the side templates is the entire outer contour of the part to be pressed, among which the lower surface of the upper pressing head and the upper surface of the lower pressing head are the upper and lower contour surfaces of the part to be pressed, and the surface can be a regular rotation surface or a symmetrical or asymmetrical concave and convex surface.

8. A self-pressurizing combined precision molding die and molding method, characterized in that: During the pressing process of the inner mold module, the radial displacement of the side mold plate produces lateral compression molding, thereby realizing self-pressurized three-dimensional precision molding and pressing; the precision molding mold can be provided with multiple ejector rods and a top-entry lateral punch system to realize local lateral molding.

9. A self-pressurizing combined precision molding die and molding processing method as claimed in claim 8, characterized in that: Utilize any one of claims 1 to 7, a self-pressurizing combined precision molding die; Workflow: Preheat separately--》Mold installation--》Place blank--》Pre-press--》Press and push in the ejector--》Press the inner mold as a whole--》Complete pressing through displacement control--》Mold stripping cylinder--》Take out the pressed parts.

10. A self-pressurizing combined precision molding die and molding method as claimed in claim 9, characterized in that: Detailed description of the workflow: (1) Apply a release agent on the working contact surface of the main mold. The release agent is a paste-like lubricant with good adhesion, such as a graphite + butter mixture; (2) Install the upper and lower heat insulation transition plates, heat insulation pads, pads, and pressure plates; the upper and lower heat insulation transition plates are fastened to the press platen through the mounting holes around the plates with T-bolts or special bolts matching the press, and the upper plates are temporarily hoisted by the upper pressure head pull rod; the lower plates except the lower pressure plate are positioned by the edge boss of the pressure plate and placed in order; Assembling the preheated inner and outer mold barrels into one piece; Insert the preheating heating rod (22) into the mold barrel; install the preheated slider, ejection punch and ejector rod into the corresponding holes of the side mold plate. The preheating method is shown in the following item (5); (3) Preheat the blank. The blank can be in the form of a block and / or powder. Set the temperature to T1, and T1 is the appropriate temperature for forming the blank. If it is powder, preheat the powder at temperature T2 under an anti-oxidation and sealing condition, and T2 < T1. For example, for an AZ80M magnesium alloy ingot, place the accurately cut magnesium alloy block that has undergone homogenization annealing in a furnace with a protective atmosphere, and T1 = 320 - 430 °C. If the material to be formed is an aluminum matrix composite: 10 - 25 vol% silicon carbide powder-reinforced aluminum alloy, such as the powder of 2000 series aluminum alloy, the accurately weighed powder can be loaded into a thin-walled iron cylinder, sealed with a lid, and placed in a furnace with a protective atmosphere, then T2 = 320 - 460 °C; The preheating time does not exceed the specified value. For example, for AZ80M magnesium alloy, the holding time after being heated through should not exceed 4 hours; for metal powder or metal matrix composite powder, such as aluminum matrix composite powder, the holding time should not exceed 2 hours; (4) Place the upper and lower punches and all side templates into a heating furnace for preheating, and set the temperature to T3; place the inner and outer mold cylinders and the upper and lower pressure plates into another heating furnace, and set the temperature to T4. If the material to be formed is AZ80M magnesium alloy, then T3 = 250 - 300 °C, T4 = 200 - 250 °C; if the material to be formed is metal powder or metal matrix composite powder, such as aluminum matrix composite powder, then T3 = 300 - 360 °C, T4＝200～250℃； (5) Install the first-round die assembly in the order of the lower pressure plate (6), lower punch (21), temporary spacer block (88), combined die cylinder (11, 12), combined die side plate (13), upper punch (14), laterally inserted 1-1 slider (15), laterally inserted die 1-1 punch (16), laterally inserted 1-2 slider (17), laterally inserted die 1-2 punch (18), laterally inserted 2-1 slider (19), laterally inserted die 2-1 punch (20) Then insert the pre-prepared inserts (29) at the gaps between each side template to keep the side templates at equal intervals; place the fully preheated block blank into the cavity surrounded by the side templates; place the upper punch (14) on the blank block, and fasten the upper pressure plate (7); turn on the heating rod (22) for preheating the die cylinder, and adjust the temperature control range to <= 300 °C; If it is powder forming, it is required that the inserts are in close contact with the side templates, and adjust the vertical position of the lower punch to make the gap with the side templates as small as possible so that the powder does not leak. Pour the preheated powder into the die cavity, and allow the die cylinder to be gently tapped to make the powder as dense as possible. Mechanical vibration or other methods can also be used to achieve powder densification; (6) Start the press. The upper platen descends and pre-presses. When the load indication of the press starts to rise significantly, stop applying pressure, raise the punch, and separate the upper pressure plate (7) and the upper 2nd backing plate (8); Remove the temporary spacer block (88) and check the alignment of the entire set of die components - it is required that the center lines of all pressure plates, backing plates, pressure plates, and punches between the upper and lower platens of the press are near the center of the press platen, and the accuracy should be better than 10 mm; If powder molding is used, after the mold cavity is completely filled with the powder, the upper pressure head (14) and the upper pressure plate (7) are placed, the press machine is started, and the pressure is slowly pressed down to about 1 / 2 of the set pressure, and the pressure is maintained constant for about 15 to 30 minutes. The pressure is then released, the press machine table is raised, the upper pressure plate (7) and the upper pressure head (14) are removed, and the powder is continued to be filled until the mold cavity is filled. The upper pressure head (14) and the upper pressure plate (7) are repeatedly placed and the pressure is applied until the quantitatively weighed powder is completely filled into the mold cavity. Finally, the pressure is slowly applied to the maximum pressure and maintained for 15 to 30 minutes. After that, the mold barrel is heated to T5 by the mold barrel preheating heating rod (22). T5 is the hot pressing temperature set for the metal-based composite material. For aluminum-based composite materials, T5≈400 to 520°C. The pressure is applied again to the pre-set hot pressing load or blank molding pressure. (7) Depressurize, remove all temporary pads (88), check the centering state of the mold; apply pressure at a pre-set pressurization speed until it is close to more than 90% of the final molding displacement (vertical displacement), depressurize again, raise the press platen, remove the upper press plate (7), place the press ring (71), make the press ring contact the ejector rod, then place the upper press plate, then slowly lower the platen to apply pressure, ensure that the pressure ring (71) and the upper press plate (7) are fully in contact, and then increase the pressure speed until the pressure reaches the set displacement. Complete precision pressing and forming; note that the excess part of the calculated quantitative blank / powder will be squeezed out from the gap between the lower pressing head and the side template to form burrs; (8) Demolding: gradually turn off the heating rod (22); raise the press platen; remove the upper platen (7); remove the pressure ring; use the lifting ring (23) set on the upper edge of the mold barrel to temporarily connect the mold barrel and the upper platen of the press, and raise the upper platen of the press again. Use the upward movement of the press platen to lift the entire mold assembly, i.e., the inner and outer mold barrels + side mold plates + upper and lower pressure heads, and insert 2 to 6 temporary pads (88) between the lower pressure head (21) and the lower pressure plate (6), evenly distributed to ensure alignment, and then lower the press platen; Insert 2 to 3 temporary pads (88) at the upper edge, cover the demoulding plate (89) at the upper edge of the inner mold barrel, place the upper plate (7) on the demoulding plate, start the press, slowly press down to achieve demoulding - that is, push the inner mold out of the mold barrel; remove the upper press head, side mold plate, ejector rod, slider and ejection punch, and finally remove the lower press head, take out the pressed part, put it in a heat preservation furnace of ~200℃, or bury it in a dry sand box, cool it to <200℃, take it out, cool it to room temperature in the air, deburr it, polish it, and send it for inspection; (9) Clean the mold, reapply the release agent, preheat separately, and repeat the process to complete the pressing of the next part.

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