Patent Publication Number: US-11648609-B1

Title: Die-casting die, die-casting device and ultra-high speed die-casting method

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the priority to Chinese patent application No. 202210067329.4, filed on Jan. 20, 2022. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification. 
     TECHNICAL FIELD 
     The present application relates to the technical field of metal die-casting, and in particular to, a die-casting die, a die-casting device and an ultra-high speed die-casting method. 
     BACKGROUND ART 
     In the existing technology, a die-casting machine and a die-casting die arranged on the die-casting machine are usually used for die-casting of metal parts. The metal liquid is pushed into the die-casting die by the die-casting machine at a specified speed. The die-casting die is provided with a pouring runner and a molding cavity, the pouring runner is communicated with the molding cavity via an ingate. The metal liquid passes through the pouring runner and enters into the molding cavity through an ingate. 
     The speed at which the metal liquid enters into the molding cavity through the ingate is a filling speed of the ingate, which is also referred to as a gate speed. The molding of metal liquid in the molding cavity is directly affected by the gate speed. If the filling speed is too low, the metal liquid will not be atomized, resulting in poor filling. In the existing technology, the gate speed is adjusted by a pushing speed adjustment of the die-casting machine. However, the die-casting machine has a preset and limited range of the device conditions. When the conditions of pushing speed reach the limit, the gate speed will also reach the upper limit. At this time, how to improve the gate speed of the die-casting die is a technical solution that needs to be solved by those skilled in the art. 
     SUMMARY 
     In order to increase the gate speed, the present application provides a die-casting die, a die-casting device and an ultra-high speed die-casting method. 
     In the first aspect, the present application provides a die-casting die, which adopts the following technical solution: 
     a die-casting die includes a die body, wherein the die body is provided with a feed port, a pouring potion and a cavity portion, the pouring potion is provided with a pouring runner communicating with the feed port, and the cavity portion is provided with a molding cavity; and wherein a gate portion is provided between the cavity portion and the pouring potion of the die body, the gate portion is provided with a plurality of ingate runners communicating with the molding cavity and the pouring runner, and the plurality of ingate runners are arranged in sequence in a width direction of a side of the gate portion facing the molding cavity; ends of the ingate runners at which the ingate runners communicate with the molding cavity constitute an ingate. 
     Different from the traditional design in the existing technology that the die-casting die is one pouring runner corresponding to one or more gate portions, and each gate portion only corresponds to one ingate runner. In this present application, the die-casting die is arranged as a structure in which one pouring runner corresponds to one or more gate portions, and each gate portion corresponds to a plurality of ingate runners. That is, the side of the gate portion facing the molding cavity is divided in the width direction perpendicular to the pouring direction, to reduce the cross-sectional area of the ingate facing the molding cavity. Under the same punch pin filling conditions, it can have a higher gate speed than the die-casting die of existing technology, to improve the filling pressure of metal liquid injecting into the molding cavity from the ingate, further to improve the gate speed of the ingate. 
     In the second aspect, the present application provides a die-casting device, which adopts the following technical solution: 
     a die-casting device includes a die-casting machine and the above mentioned die-casting die, the die-casting machine comprises an injection mechanism for pushing metal liquid into the die-casting die at a specified speed; the injection mechanism comprises a barrel and a punch pin arranged in the barrel; the barrel is provided with a feed end for feeding metal liquid and a discharge end for discharging metal liquid; the punch pin is configured for pushing metal liquid; the feed port of the die-casting die communicates with the discharge end of the barrel. 
     By the high-speed and fast injection function of the die-casting machine, the metal liquid can be instantaneously and rapidly pressurized to fill the die-casting die, to improve the pressure effect, so that the pressure can act on the molding cavity of the whole die-casting die, to improve the molding air tightness and molding stability in the molding cavity. 
     In the third aspect, the present application provides an ultra-high speed die-casting method, which adopts the following technical solution: 
     an ultra-high speed die-casting method for die casting with the above mentioned die-casting device includes the following steps: 
     preheating the die-casting die; 
     pouring the molten metal liquid into the barrel of the die-casting machine, and a pushing speed of the punch pin is less than 0.7 m/s; vacuumizing the die-casting die when the punch pin is pushed to block the feed end of the barrel; at the same time, continuing to push the metal liquid to fill the gate portion of the die-casting die; 
     increasing the pushing speed of the punch pin instantly when filling the metal liquid into the gate portion of the die-casting die, the pushing speed of the punch pin of the die-casting machine is 1-8 m/s; 
     pushing the metal liquid to spray the metal liquid into the molding cavity from the gate portion in a form of atomization, and a gate speed is 65-120 m/s; 
     after the filling of the molding cavity is completed, reducing the pushing speed of the punch pin and pressurizing the die-casting machine to 70-100 MPa; and 
     cooling, molding and demoulding to obtain a required metal die casting. 
     By the ultra-high speed die-casting method, the metal liquid is pushed at a low speed in the early stage to make the metal liquid flow to the gate portion at a steady and uniform speed, and the fluctuation and air entrainment of the metal liquid can be reduced in the process; at the same time, when the metal liquid is filled to the gate portion, it will be pressurized instantaneously to reduce the pressure loss when the metal liquid does not reach the gate portion, to improve the direct effect of the pressure at the gate portion, the pressure effect of the metal liquid injecting into the molding cavity from the ingate of the gate portion, and the gate speed, to achieve the effect of ultra-high speed atomization filling; in the later stage of filling, the pushing speed is decelerated, which is conducive to reduce the excessive overflow, flash and other die-casting defects caused by the continuous high-pressure filling of molten liquid, to improve the die-casting effect. 
     To sum up, the present application includes at least one of the following beneficial technical effects: 
     1. the design of a plurality of ingate runners is adopted, reducing the cross-sectional area of the ingate facing the molding cavity, greatly improving the gate speed of the die-casting die; the gate speed can reach 65-120 m/s, the filling time is as low as 0.006-0.08 t/s; the filling pressure is large, which can realize ultra-high-speed die-casting with the gate speed greater than 60 m/s and improve the filling effect of metal liquid; the metal liquid is sprayed into the molding cavity in the form of atomization, and the residual air in the molding cavity is broken into fine bodies, to fully compress the pores of the metal forming parts obtained by die-casting, and the pore volume ratio is compressed to 0.01%, to homogenize the metallographic structure and improve the molding effect of the metal parts, it is especially convenient to make metal products with high requirements such as porosity less than 0.2%, dense surface and high finish, or T6 treatment. 
     2. An acceleration portion is arranged between the pouring potion and the gate portion of the die-casting die. The acceleration slot with first descending and then ascending is arranged in the acceleration portion improving the filling speed and filling pressure of the metal liquid to the gate portion, further to improve the gate speed of the die-casting die and be used for die-casting of ultra-thin parts below 0.8 mm. 
     3. The method of instantaneous pressurization filling is adopted to reduce the pressure loss in the early stage, to improve the direct effect of pressure on the gate portions, the pressure effect of metal liquid injecting into the molding cavity from the ingate of the gate portions, and the gate speed, to achieve the effect of ultra-high speed atomization filling. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic diagram of an overall structure of a die-casting die according to Embodiment  1  of the present application. 
         FIG.  2    is a schematic structural exploded diagram of the die-casting die according to Embodiment 1 of the present application. 
         FIG.  3    is an enlarged view of a portion A in  FIG.  2   . 
         FIG.  4    is a schematic structural diagram of a moving die core according to Embodiment 1 of the present application. 
         FIG.  5    is an enlarged view of a portion B in  FIG.  4   . 
         FIG.  6    is a schematic structural diagram of a fixed die core according to Embodiment 1 of the present application. 
         FIG.  7    is an enlarged view of a portion C in  FIG.  6   . 
         FIG.  8    is a schematic partial structural diagram of a metal die-casting blank manufactured by using the die-casting die according to Embodiment 1 of the present application, which mainly illustrates the shape and structure of the pouring runner, acceleration slot and ingate runner. 
         FIG.  9    is a schematic structural diagram of a moving die core according to Embodiment 2 of the present application. 
         FIG.  10    is a schematic structural exploded diagram of the moving die core according to Embodiment 2 of the present application. 
         FIG.  11    is a schematic structural diagram of the moving die core in an unassembled state according to Embodiment 2 of the present application. 
         FIG.  12    is a SEM diagram of a metal casting obtained according to Embodiment 4 of the present application. 
         FIG.  13    is a SEM diagram of a metal casting obtained according to Embodiment 5 of the present application. 
         FIG.  14    is a SEM diagram of a metal casting obtained according to Embodiment 6 of the present application. 
       In particular,  FIGS.  12 - 14    are views observed at 500 times magnification of a metallographic electron microscope. 
     
    
    
     DETAILED DESCRIPTION 
     The present application is described in further detail below with references to  FIGS.  1 - 14   . 
     Embodiment 1 
     Referring to  FIG.  1   , a die-casting die includes a die body  1 . The die body  1  includes a fixed die module  2  and a moving die module  3  for opening and closing with the fixed die module  2 . 
     Referring to  FIGS.  1  and  2   , the moving die module  3  includes a moving die frame  31 . The moving die frame  31  is provided with guide pillars  311  for slidably connecting with the fixed die module  2 . A die base  312  is provided on a side of the moving die frame  31  away from the fixed die module  2 , and the moving die frame  31  is fixedly arranged on a die-casting machine used with the die-casting die by means of the die base  312 . 
     Referring to  FIGS.  2  and  3   , a moving die mounting slot  313  is formed on a side of the moving die frame  31  facing the fixed die module  2 . A sprue spreader  32  and a moving die core  33  are arranged in the moving die mounting slot  313 . A side wall of the moving die core  33  abuts against a circumferential side wall of the sprue spreader  32 . One side of the sprue spreader  32  facing the fixed die module  2  protrudes upwards to form a sprue spreader frustum  321 . A sprue spreader slot  322  for dividing metal liquid is formed on a side of the sprue spreader frustum  321  facing the moving die core  33 . A moving die pouring runner  331  communicating with the sprue spreader slot  322  is formed on a side of the moving die core  33  close to the sprue spreader  32 . The moving die pouring runner  331  extends obliquely downward in a pouring direction. The number of moving die pouring runners  331  corresponds to the number of the sprue spreader slot  322  one by one. A moving die acceleration cavity  332  is provided on the moving die core  33  at one end of each moving die pouring runner  331  away from the sprue spreader  32 . A moving die acceleration slot  3321 , communicating with a corresponding moving die pouring runner  331 , is provided at bottom of each moving die acceleration cavity  332 . The moving die acceleration slot  3321  firstly descends and then goes up in the pouring direction. When the die-casting die is clamped for die casting, the metal liquid flows through the sprue spreader  32 , the moving die pouring runner  331  and the moving die acceleration slot  3321 . Due to the downward extension of the moving die pouring runner  331  and the descending and going up of the moving die acceleration slot  3321 , the metal liquid may form a U-shaped communicating portion in the pouring direction. By means of a characteristic that the liquid pressure on both sides of the U-shaped communicating portion is balanced, the pressure transmission effect of metal liquid in the pouring direction can be enhanced and the pouring speed of metal liquid can be increased. 
     Referring to  FIGS.  4  and  5   , on the moving die core  33 , a moving die gate portion  333  and a moving die cavity  334  are provided on a side of each moving die acceleration cavity  332  away from the moving die pouring runner  331  successively in the pouring direction. A plurality of moving die ingate notches  3331  are formed on the moving die gate portion  333 , and the moving die ingate notches  3331  are arranged successively in a width direction of a side of the moving die gate portion  333  facing the moving die cavity  334 . The moving die ingate notches  3331  communicate with the moving die acceleration slot  3321  and the moving die cavity  334 . The diameter of the moving die ingate notches  3331  gradually decreases in the pouring direction. When the metal liquid flows through the moving die ingate notches  3331  and enters the moving die cavity  334 , the gradually decreased diameter can enhance the concentrated pressure effect of the metal liquid in the moving die ingate notches  3331 , increase the filling pressure of the metal liquid, and increase the gate speed. 
     Referring to  FIGS.  4  and  5   , a moving die guide head  3332  is arranged on the moving die gate portion  333  between two adjacent moving die ingate notches  3331 . The moving die guide heads  3332  protrude towards the moving die accelerating slot  3321  to form an arc-shaped heads. The moving die guide head  3332  conforms to the pouring direction of the metal liquid, which can effectively reduce the flow resistance of the moving die gate portion  333  to the metal liquid, increase the speed at which the metal liquid enters into the moving die cavity  334  through the moving die ingate notch  3331  and the gate speed. 
     Referring to  FIGS.  2  and  4   , on the moving die core  33 , a moving die limit slot  335  is provided on a side of the moving die cavity  334  away from the moving die gate portion  333 . The moving die limit slot  335  communicates with the moving die cavity  334 . A moving die sliding slot  314  is provided on the moving die frame  31 , which communicates with the moving die limit slot  335 . A sliding table  4  is slidably arranged on the moving die sliding slot  314 , and a limiting table  41  is arranged on a side of the sliding table  4  facing the moving die cavity  334 . When the moving die module  3  and the fixed die module  2  are clamped together, the sliding table  4  slides towards the moving die cavity  334 , and the limiting table  41  abuts against the moving die limit slot  335  for sealing one side of the moving die cavity  334 . When the moving die module  3  and the fixed die module  2  are separated, the sliding table  4  slides away from the moving die cavity  334 , and the limiting table  41  is separated from the moving die limit slot  335 , which facilitates the demoulding of the metal molding parts in the moving die cavity  334 . The sliding table  4  is used for the installation of the die casting die to a die-casting machine. 
     Referring to  FIGS.  2  and  4   , a vacuum hole  336  is provided through the moving die core  33 , which is used for communicating and installing of a vacuum equipment with the die-casting die, and is used for vacuum pumping and exhausting. The moving die frame  31  is provided with a connecting hole communicating with the vacuum hole  336  (not shown in the drawings). 
     Referring to  FIGS.  2  and  4   , on the moving die core  33 , an overflow groove  337  is provided on a side of the moving die cavity  334  away from the moving die gate portion  333 , and an exhaust groove  338  is provided on a side of the overflow groove  337  away from the moving die cavity  334 . The exhaust groove  338  communicates with the vacuum hole  336 . The exhaust groove  338  is used to guide gas discharge during vacuum pumping and exhausting, so as to improve the guidance of gas extraction and discharge of metal liquid in the moving die cavity  334  and reduce the defects of forming pores and the probability of blockage of the vacuum hole  336  caused by the metal liquid flowing with the gas. A filter block  339  is arranged on an exhaust path of the exhaust groove  338 , which is located between the vacuum hole  336  and the overflow groove  337 . The filter block  339  is a microporous metal sintered block. The filter block  339  is used for metal liquid interception and ventilation to reduce the metal flow channeling. 
     Referring to  FIGS.  2  and  4   , a moving die cooling communicating groove  3310  is provided on the moving die core  33 , which penetrates through the moving die core  33 . A moving die cooling port  315 , communicating with the moving die cooling communicating groove  3310 , is provided on the moving die frame  31 . The moving die cooling port  315  is used for the installation of a cooling device on the die-casting die. The cooling device can be a cold water circulation system or a cold air circulation system, as long as it can be used for cooling. By the moving die cooling communicating groove  3310 , the moving die cavity  334  of the moving die core  33  can be cooled comprehensively and rapidly, so as to improve the die casting. 
     Referring to  FIGS.  2 ,  6  and  7   , the fixed die module  2  includes a fixed die frame  21  for fixed installation of a die-casting die to a die-casting machine. A guide sleeve  211  for slidably connecting with the guide pillar  311 , a pouring sleeve  22  for sleeving on the sprue spreader  32 , and a fixed die core  23  with a shape matching with the moving die core  33  are arranged on a side of the fixed die frame  21  facing the moving die module  3 . The fixed die frame  21  is also provided with a feed port  212  for communicating with a discharge end of the die-casting machine, and the feed port  212  communicates with the pouring sleeve  22 . 
     Referring to  FIGS.  6  and  7   , a fixed die cavity  231  is arranged on a side of the fixed die core  23  facing the moving die module  3 . On the fixed die core  23 , a fixed die acceleration portion  232  is arranged on a side of the fixed die cavity  231  close to the pouring sleeve  22 . The fixed die accelerating portion  232  protrudes towards the moving die module  3 , and descends first and then goes up in the pouring direction. A fixed die accelerating groove  2321  is formed on a side of the fixed die acceleration portion  232  facing the fixed die cavity  231 . 
     Referring to  FIGS.  6  and  7   , on the fixed die core  23 , a fixed die gate portion  233  is arranged on a side of the fixed die accelerating portion  232  facing the fixed die cavity  231 . The shape of the fixed die gate portion  233  fits to the shape of the moving die gate portion  333 . A plurality of fixed die ingate notches  2331  are arranged on the fixed die gate portion  233 , which communicate with the fixed die accelerating groove  2321  and the fixed die cavity  231 , and the fixed die ingate notches  2331  are in one-to-one correspondence with the moving die ingate notches  3331 . 
     Referring to  FIGS.  2  and  6   , on the fixed die core  23 , a fixed die limit slot  234  is arranged on a side of the fixed die cavity  231  away from the fixed die gate portion  233 . The fixed die limit slot  234  communicates with the fixed die cavity  231 . The fixed die frame  21  is provided with a fixed die sliding slot  213  corresponding to and communicating with the fixed die limit slot  234 . When the fixed die module  2  and the moving die module  3  are clamped together, the fixed die cavity  231  and the moving die cavity  334  constitute a molding cavity, the fixed die limit slot  234  and the moving die limit slot  335  constitute a molding cavity limit slot communicating with the molding cavity, the fixed die sliding slot  213  and the moving die sliding slot  314  constitute a die sliding slot communicating with the molding cavity limit slot, and the sliding table  4  slides in the die sliding slot and drives the limiting table  41  to abut against the molding cavity limit slot. 
     Referring to  FIGS.  2  and  6   , the fixed die frame  21  is provided with an oblique dowel pin  5 . The oblique dowel pin  5  extends from the fixed die module  2  to the moving die module  3 . One end of the oblique dowel pin  5  is inserted into the sliding table  4 . When the fixed die module  2  and the moving die module  3  are clamped together, the sliding table  4  is fixed by the oblique dowel pin  5  so as to reduce the possibility that the sliding table  4  slides in the die sliding groove when the sliding table  4  is impacted by metal liquid pressure. 
     Referring to  FIGS.  2  and  6   , insertion slots  235  are provided on the fixed die core  23  at positions corresponding to the filter blocks  339  of the moving die module  3 , which is used for the insertion and installation of the filter blocks  339  of the moving die module  3 . The fixed die core  23  is also provided with a fixed die cooling through groove  236  that penetrates through the fixed die core  23 . The fixed die frame  21  is provided with a fixed die cooling port  214  communicating with the fixed die cooling through groove  236 . The fixed die cooling port  214  is used for the installation of a cooling device for use with the die-casting die. The cooling device may be a cold water circulation system or a cold air circulation system, as long as it can be used for cooling. By the fixed die cooling through groove  236 , the fixed die cavity  231  of the fixed die core  23  can be cooled comprehensively and rapidly, so as to improve the effect of die casting. 
     Referring to  FIG.  8   , when the fixed die module  2  and the moving die module  3  are clamped together, the sprue spreader frustum  321  on the sprue spreader  32  of the moving die module  3  is sleeved into the pouring sleeve  22  of the fixed die module  2 . The sprue spreader  32  and the pouring sleeve  22  constitute a pouring portion of the die body  1 . A annular runner formed by the pouring sleeve  22  and the sprue spreader frustum  321 , the sprue spreader slot  322  on the sprue spreader frustum  321  and the moving die pouring runner  331  constitute a pouring runner of the die body  1 . The fixed die accelerating portion  232  is arranged in the moving die accelerating cavity  332  to form the accelerating part of the die body  1 , the fixed die accelerating groove  2321  and the moving die accelerating slot  3321  constitute the accelerating groove of the die body  1 , the fixed die gate portion  233  and the moving die gate portion  333  constitute the gate portion of the die body  1 , and the fixed die ingate notch  2331  and the moving die ingate notch  3331  constitute the ingate runner of the die body  1 , the fixed die cavity  231  and the moving die cavity  334  constitute the molding cavity of the die body  1 , and the communicating end between the ingate runner and the molding cavity is the ingate of the die body  1 . The width of the ingate runner decreases gradually in the pouring direction. 
     Referring to  FIG.  8   , when the die-casting die is clamped for die casting, the molten metal liquid enters into the pouring sleeve  22  from the feed port  212  of the fixed die module  2 , and is shunted by the sprue spreader frustum  321  at the sprue spreader  32 . The shunted metal liquid flows through the corresponding sprue spreader slot  322 . Specifically, the metal liquid successively flows through the sprue spreader slot  322 , the moving die pouring runner  331 , the acceleration slot and the ingate runner, and is injected into the molding cavity via the ingate under a high pressure. After the molding cavity is filled with the metal liquid, the metal liquid may overflow into the overflow groove  337  communicating with the molding cavity. The interior of the die-casting die can be vacuumized through the vacuum hole  336  to reduce the pore defects after metal liquid molding. In vacuumizing, the air flow is guided by means of the exhaust groove  338  communicating with the overflow groove  337  to reduce the flow channeling of metal liquid. The filter block  339  of the exhaust groove  338  is used for air ventilation and metal liquid interception to reduce the blockage of the vacuum hole  336 . The metal liquid in the molding cavity is cooled and molded by means of the fixed die cooling port  214 , the fixed die cooling through groove  236 , the moving die cooling port  315  and the moving die cooling communicating groove  3310 . 
     In this embodiment, the fixed die core  23  and the moving die core  33  are made of a high temperature resistant nickel base alloy material with strengthening by solid solution of tungsten and molybdenum and with grain boundaries strengthening by boron, cerium and chromium, which have high hardness and high temperature resistance. The fixed die gate portion  233  of the fixed die core  23  and the moving die gate portion  333  of the moving die core  33  are coated with anti-corrosion coatings respectively, for example, an AlCrN coating. The surface hardness of the fixed die gate portion  233  and the moving die gate portion  333  reaches 3500 HV, which enhances the erosion resistance of the fixed die gate portion  233 , the moving die gate portion  333 , and the gate of the die body  1 . 
     The section shape of the ingate in die body  1  facing the molding cavity may be circular or rectangular, which may be determined according to the structural characteristics of the metal die castings that can be molded in the molding cavity. Referring to  FIG.  8   , in this embodiment, the section shape of the ingate facing the molding cavity is rectangular. In this embodiment, the length and width of the section shape of the ingate facing the molding cavity are 3.4 mm and 2.4 mm, that is, the section area of the ingate facing the molding cavity is S pouring =3.4 mm×2.4 mm=8.16 mm 2 . At the same time, there are multiple ingates on the die body  1 , that is, N ingates. Specifically, a sprue spreader slot  322  corresponds to a pouring runner, a pouring runner corresponds to an acceleration portion, an acceleration portion corresponds to a gate portion, a gate portion corresponds to a molding cavity, and six ingates are arranged on one gate portion for communicating with the molding cavity. In an embodiment, two gate portions and two molding cavities are provided on the die body  1 , that is, twelve ingates are provided, that is, N=12. Therefore, in this embodiment, the total sectional area of the gate of the die body  1  is S total-pouring =N×S pouring =12×8.16 mm 2 =98 mm 2 . 
     Embodiment 2 
     Referring to  FIG.  9 ,  10  and  11   , a die-casting die is provided according to Embodiment 2. The die-casting die of Embodiment 2 is different from Embodiment 1 in that: 
     the moving die gate portion  333  of the moving die module  3  is detachably arranged on the moving die core  33 , and the fixed die gate portion  233  of the fixed die module  2  is detachably arranged on the fixed die core  23 . Specifically, a gate mounting slot  6  is provided on the moving die core  33 , a positioning block  61  is arranged in the gate mounting slot  6 , and the positioning block  61  protrudes from the bottom of the gate mounting slot  6 . A positioning groove  3333 , corresponding to the positioning block  61 , is provided on a side of the moving die gate portion  333  facing the moving die core  33 . In installation, the moving die gate portion  333  is placed in the gate mounting slot  6 , the positioning groove  3333  fits to the positioning block  61 , the positioning block  61  is inserted into the positioning groove  3333 , and the positioning block  61  positions and guides the moving die gate portion  333 , to reduce the displacement phenomenon when the moving die gate portion  333  is embedded into the gate mounting slot  6 , and improve the stability of embedded installation and installation. It should be noted that, a plurality of positioning blocks  61  may be provided, and the number of the positioning grooves  3333  is consistent with the number of the positioning blocks  61 . The number of positioning blocks  61  can be determined according to requirements for the size of the moving die gate, in order to implement stable positioning, guide and installation. Moreover, in order to improve the installation stability, an installation through-hole (not shown in the drawing) may also be provided on a side of the moving die core  33  away from the gate mounting slot  6 , which communicates with the gate mounting slot  6 . A threaded hole is provided on the moving die gate portion  333  at a position corresponding to the installation through-hole. With communicating of the installation through-hole with the threaded hole, the moving die gate portion  333  may be further installed and fixed by using fixing parts such as screws. The detachable mounting structure of the fixed die gate portion  233  and the fixed die core  23  is the same as that of the moving die gate portion  333  and the moving die core  33 . The moving die gate portion  333  and the fixed die gate portion  233  may be replaced by means of such a detachable installation. The moving die gate portion  333  and the fixed die gate portion  233  are made of a high temperature resistant nickel base alloy material with strengthening by solid solution of tungsten and molybdenum and with grain boundaries strengthening by boron, cerium and chromium, which have high hardness and high temperature resistance. 
     The filter block  339  is detachably arranged on the moving die core  33 . The detachable mounting structure of the filter block  339  and the moving die core  33  is the same as that of the moving die gate portion  333  and the moving die core  33 . The filter block  339  may be replaced by means of such a removable installation. The filter block  339  is a microporous metal sintered block. The microporous metal sintered block is a metal material block with ventilation micropores by cold pressing, sintering and heat treatment of metal powder. 
     Embodiment 3 
     a die-casting device includes a die-casting machine and a die-casting die according to Embodiment 1. 
     The die-casting machine includes a clamping mechanism for driving the die-casting die to be opened and clamped and an injection mechanism for injecting metal liquid into the die-casting die at a specified speed. 
     The clamping mechanism includes a fixed die mounting plate, a moving die mounting plate, and a driving-clamping device for driving the moving die mounting plate to move towards or away from the fixed die mounting plate. The fixed die module of the die-casting die is installed on the fixed die mounting plate by the fixed die frame, and the moving die module of the die-casting die is installed on the moving die mounting plate by the moving die frame. 
     The injection mechanism includes a barrel, a punch pin arranged in the barrel, and a pushing device for pushing the punch pin. The barrel is provided with a feed end for feeding the metal liquid and a discharge end for discharging the metal liquid. The punch pin is used to push the metal liquid. The feed port of the fixed die module of the die-casting die communicates with the discharge end of the barrel. The barrel is made of titanium alloy ceramic material, and the thermal conductivity of the barrel is 7.4 W/mk. The barrel with low thermal conductivity helps to keep the metal liquid at high temperature before entering the die-casting die. 
     In the process of die casting, S punch ×V punch =S total pouring ×V pouring , in which V pouring  is a gate speed of the ingate, S punch  is a cross-sectional area of the punch pin of the die-casting machine facing the pushing direction, and V punch  is a pushing speed of the die-casting machine. Therefore, the gate speed of the die-casting die in the process of die casting, V pouring =S punch ×V punch /S total pouring . 
     In this embodiment, the punch pin diameter of the punch pin in the barrel is 60 mm, and the punch pin area S punch =πR 2 =π×30 2 ≈2827 mm 2 . If the pushing speed of the punch pin is arranged as V punch =3.2 m/s. Then in this embodiment, the gate speed of the die-casting die is V pouring =S flushing ×V flushing /S total pouring =2827×3.2/98≈92 m/s. In this embodiment, the gate speed of the die-casting die can reach 92 m/s, and the die-casting device in this embodiment can carry out ultra-high speed die casting. 
     The gate speed of the die-casting device can reach 92 m/s, so that the metal liquid can be sprayed into the molding cavity in the form of atomization. The residual air in the molding cavity is broken into micro fine bodies to fully compress the pores of the metal forming parts obtained by die casting. The pore volume ratio is compressed to 0.01%, to homogenize the metallographic structure and improve the forming effect of the metal parts. It is especially convenient to make metal products with high requirements such as porosity less than 0.2%, dense surface and high finish, or T6 treatment. 
     Embodiment 4 
     an ultra-high speed die casting method by using the die-casting device according to Embodiment 3, including the following steps: 
     preheating the die-casting die and controlling the die-casting die temperature to 220-230° C.; 
     pouring the molten magnesium alloy metal liquid into the barrel of the die-casting machine, and the pushing speed of the punch pin is 0.7 m/s; vacuumizing the die-casting die when the punch pin is pushed to block the feeding end of the barrel; at the same time, continuing to push the metal liquid to fill the gate portion of the preheated die-casting die; in this process, the pushing speed of punch pin starts from 0 m/s and gradually increases to 0.7 m/s; it should be noted that, the pushing speed may also be directly set to 0.7 m/s, the pushing speed of 0.7 m/s may be maintained continuously during the process. In this embodiment, the setting of increasing from 0 m/s to 0.7 m/s is adopted; 
     increasing the pushing speed of the punch pin instantly when the metal liquid is filled into the gate portion of the preheated die-casting die; the pushing speed of the punch pin is 3.2 m/s, so that the gate speed of the ingate of the gate portion reaches 92 m/s; pushing the metal liquid to spray the metal liquid into the molding cavity from the gate portion in a form of atomization; 
     after filling the molding cavity, reducing the pushing speed of the punch pin and pressurizing the die-casting machine to 100 MPa; 
     cooling, molding and demoulding to obtain a required metal die casting. 
     In particular, the moment of the metal liquid reaching the gate portion of the die-casting die or the metal liquid filling the molding cavity can be determined by the existing general pouring simulation software in the technical field, combined with the simulation conversion of die-casting die parameters, die-casting machine barrel parameters, stamping parameters and metal liquid quality parameters. 
     The ultra-high speed die casting method adopts the method of instantaneous pressurization and filling to reduce the pressure loss in the early stage, to improve the direct effect of pressure at the gate portion, the pressure effect of metal liquid injecting into the molding cavity from the ingate of the gate portion and the gate speed, to achieve the effect of ultra-high speed atomization and filling. 
     Referring to  FIG.  8   , the obtained metal casting is a multi-blade heat sink with a blade thickness of 0.8 mm The SEM diagram of the metal casting obtained in Embodiment 4 is shown in  FIG.  12   , which has good forming effect, uniform metallographic structure, few pore defects, no surface streamline trace and small grains. 
     Embodiment 5 
     Embodiment 5 differs from Embodiment 4 is in the gate speed of the die-casting die during die-casting. In Embodiment 5, the cross-sectional area of the ingate of the die-casting die facing the molding cavity is S pouring =11.60 mm 2 , the total gate cross-sectional area is S pouring =N×S pouring =12×11.60 mm 2 =139.2 mm 2 , and the gate speed of the die-casting die is V pouring =S punch ×V punch /S total pouring =2827×3.2/139.2≈65 m/s. The SEM diagram of the metal casting obtained in Embodiment 5 is shown in  FIG.  13   , which has good forming effect, uniform metallographic structure, few pore defects, less surface streamline trace and small grains. 
     Embodiment 6 
     Embodiment 6 differs from Embodiment 4 is in the gate speed of the die-casting die during die-casting. In Embodiment 6, the cross-sectional area of the ingate of the die-casting die facing the molding cavity is S pouring =6.85 mm  2 , the total gate cross-sectional area is S pouring =N×S pouring =12×6.85 mm 2 =82.2 mm 2 , and the gate speed of the die-casting die is V pouring =S punch ×V punch /S total pouring =2827×3.2/82.2≈110 m/s. The SEM diagram of the metal casting obtained in Embodiment 6 is shown in  FIG.  14   , which has good forming effect, uniform metallographic structure, few pore defects, no surface streamline trace and small grains. 
     The above are the preferred embodiments of the present application and do not limit the scope of protection of the present application. Therefore, all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the scope of protection of the present application.