Semi-solid metal in-cavity molding die

Abstract

A semi-solid metal in-cavity molding die includes a die body. The die body includes a male die and a female die, a cavity formed by the male die and the female die, a runner communicated with the cavity and a sprue communicated with the runner are provided inside the die body. An inner wall of the runner is provided with a plurality of guide protrusions which are arranged in a spiral track. The guide protrusions combine the inner wall of the runner to form a special-shaped pipeline for molten metal to flow through, and a cooling mechanism arranged around the runner is further provided in the die body.

Claims

1. A semi-solid metal in-cavity molding die, comprising a die body, wherein the die body comprises a male die and a female die; provided inside the die body are a cavity formed by the male die and the female die, a runner communicated with the cavity and a sprue communicated with the runner, and an inner wall of the runner is provided with a plurality of guide protrusions arranged in a spiral track, the guide protrusions and the inner wall of the runner form a profiled pipeline for molten metal to flow through, and a cooling mechanism arranged around the runner is further provided in the die body.

2. The semi-solid metal in-cavity molding die according to claim 1, wherein the runner comprises multiple runners, and two ends of each of the runners are respectively communicated with the sprue and the cavity.

3. The semi-solid metal in-cavity molding die according to claim 2, wherein a confluence cavity communicated with the cavity is provided in the die body, and the two ends of each of the runners are respectively communicated with the sprue and the confluence cavity.

4. The semi-solid metal in-cavity molding die according to claim 2, wherein the runners are arranged side by side, and a number of the runners is not less than two.

5. The semi-solid metal in-cavity molding die according to claim 2, wherein the runners are arranged at equal intervals circumferentially around one straight line, and a number of the runners is not less than three.

6. The semi-solid metal in-cavity molding die according to claim 2, wherein the cooling mechanism is a spiral channel around each of the runners, and two ends of the cooling mechanism are communicated with an external cooling water circulation conveying device.

7. The semi-solid metal in-cavity molding die according to claim 2, wherein a plurality of lines are provided in the inner wall of each runner, and each of the lines is circumferentially arranged along the inner wall of the runner or arranged as a thread line along the inner wall of the runner.

8. The semi-solid metal in-cavity molding die according to claim 2, wherein a runner component is detachably mounted in the die body, and each of the runners is included in the runner component.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure.

(2) FIG. 1 is a schematic view showing a use state of Example 1;

(3) FIG. 2 is an enlarged view of the portion A of FIG. 1;

(4) FIG. 3 is a schematic view showing the shape of the waste material at each part of Example 1;

(5) FIG. 4 is a schematic view showing the shape of the waste material at each part of Example 2;

(6) FIG. 5 is a schematic view showing the mounting position of the runner component improved by Example 1;

(7) FIG. 6 is a schematic view showing the mounting position of the runner component improved by Example 2;

(8) FIG. 7 is a schematic view showing the shape of the waste material at each part of Example 3;

(9) FIG. 8 is a schematic view showing the shape of the waste material at each part of Example 4; and

(10) FIG. 9 is a schematic view showing the shape of the waste material at each part of Example 5.

DESCRIPTION OF THE EMBODIMENTS

(11) The present invention will now be described in detail with reference to the accompanying drawings and examples.

Example 1

(12) a semi-solid metal in-cavity molding die, as shown in FIGS. 1 and 2, comprises a die body 1, and inside the die body 1, provided are a cavity 14 used for molding a casting 5, a sprue 13 communicated with a discharge port of an external pressure injection device and used for receiving molten metal, multiple runners 2 arranged side by side with two ends of each respectively molded with the sprue 13 and the cavity 14 for molding a semi-solid metal melt, and a cooling mechanism 4 arranged around each runner 2; wherein the die body 1 includes a female die 12 fixedly mounted on a die casting machine and a male die 11 movably connected to the die casting machine.

(13) As shown in FIGS. 2 and 3, runners 2 are arranged side by side, and the number of the runners is not less than two (the drawings of the present description specifically disclose an arrangement where the number of the runners is three), and a plurality of guide protrusions 21 are arranged in a spiral track on the inner wall of each runner 2.

(14) Specifically, as shown in FIGS. 2 and 3, guide protrusions 21 in one runner 2 is arranged on two randomly arranged symmetrical surfaces of the runner 2, moreover, guide protrusions 21 are arranged in a staggered manner along the length direction of the runner, such that a special-shaped pipeline featuring a wave shape is formed by the inner wall of the runner 2 and guide protrusions 21 (wave crests and wave troughs of the wave line are connected with the thread line), the cross section of the special-shaped pipeline can be in a rectangular shape or in a circular shape, and this Example specifically discloses a structural schematic diagram showing the cross section in a circular shape.

(15) As shown in FIG. 2, a confluence cavity 3 communicated with one end, far away from the sprue 13, of each runner 2 is further provided in the die body 1, and one end, far away from the runner 2, of the confluence cavity 3 is necked; further, the cavity 14 in the die body 1 may be provided with a plurality of passages, each of which is provided in communication with the confluence chamber 3. As shown in FIG. 3, when the semi-solid metal melt is completely cooled and formed, the casting 5, a confluence chamber waste 51, a runner waste 52 and a sprue waste 53 filled in the cavity 14, the confluence chamber 3, the runner 2 and the sprue 13, respectively, are formed in the die body 1, and the casting 5, the confluence chamber waste 51, the runner waste 52 and the sprue waste 53 are formed in the same shape and size as the cavity 14, the confluence chamber 3, the runner 2 and the sprue 13.

(16) As shown in FIGS. 1 and 2, the cooling mechanism 4 is provided as a spiral channel, two ends of which are respectively communicated with the water inlet port and the water outlet port of the external condensed water circulation conveying device outside the die body 1, and the spiral channel is disposed around each runner 2, the water inlet port of the spiral channel is close to the sprue 13, and the water outlet port of the spiral channel is close to the confluence cavity 3; the spiral channel are divided into a plurality of sections that are arranged on the male die 12 and the female die 11 at intervals, and when the male die 12 and the female die 11 are combined, all the sections reach communication.

Example 2

(17) the present example differs from Example 1 in that each runner 2 is arranged at equal intervals circumferentially around one central line, and the number of runners 2 is not less than three, and in one runner 2, guide protrusions 21 are arranged in a spiral track along the inner wall of the runner, with at least three guide protrusions 21 distributed in one circle of the spiral track, in this manner, a special-shaped pipeline arranged spirally is formed by the runner 2 and guide protrusions 21; and further, runners 2 can be spirally arranged around one central line (particularly, waste formed when the runner is in a spiral special-shaped pipeline shape and runners are spirally arranged around one central line is disclosed in FIG. 4), as shown in FIG. 4, according to the above solution, after the semi-solid metal melt is completely cooled and formed, the casting 5, the confluence chamber waste 51, the runner waste 52 and the sprue waste 53 which are the same in shape and size as the cavity 14, the confluence chamber 3, the runner 2 (spirally arranged) and the sprue 13 respectively are formed in the die body 1; compared with Example 1, the spirally arranged runner 2 has a larger inner wall surface area than a wavy runner 2, the semi-solidification effect of the molten metal is better, but it's difficult to take out the formed waste material.

(18) Furthermore, lines 22 are provided in the inner wall of each runner 2 and are arranged along the length direction of the runner 2 at equal intervals circumferentially along the inner wall. As shown in FIG. 3, according to the improved solution, waste lines 521 spirally arranged around the length direction of the runner waste 52 are formed on the runner waste 52; wherein each of the lines 22 may also be spirally arranged along the length direction of the runner 2, and as shown in FIG. 4, according to the improved solution, waste lines 521 spirally arranged around the length direction of the runner waste 52 are formed on the runner waste 52. When the molten metal flows in the runner 2, the effect of increasing the contact area between the molten metal and the inner wall of the runner 2 because of the lines 22 will be achieved, so that shearing friction force is more likely to generate to form a semi-solid metal melt, and when the semi-solid metal melt is solidified, the semi-solid metal melt in the runner 2 fills the lines 22 to form waste lines 521, and the shape of the waste lines 521 will be formed the same as the lines 22 provided in the inner wall of the runner 2.

(19) Furthermore, as shown in FIGS. 5 and 6, a runner component 6 is provided in the die body 1, each runner 2 is included in the runner component 6, and the runner component 6 is detachably mounted in the die body 1 by means of magnetic fixing, bolt locking, clamping fixing and the like; specifically, the runner component 6 includes a male core 61 and a female core 62, a plurality of curved grooves which are mutually matched to form the runner 2 are formed on the mutually matched surfaces of the male core 61 and the female core 62, and the number of the male cores 61 can be set according to the curved track of the runner 2.

(20) Part of the cooling mechanism 4 can be arranged in the runner component 6, in this manner, the two ends of the cooling mechanism 4 are located in the die body 1, and when the runner component 6 is mounted in the die body 1, the part of the cooling mechanism 4 in the runner component 6 are communicated with the part in the die body 1 to form the complete cooling mechanism 4.

(21) Furthermore, the guide protrusions 21 can also be arranged in a double-spiral track shape, specifically, by utilizing the matching relationship between the positions and the shapes of the guide protrusions 21, the inner wall of the runner 2 and the guide protrusions 21 can form other special-shaped pipeline structures capable of enabling molten metal to generate laminar flow, excessive flow, turbulence and the like; the major characteristics lie in a plurality of guide protrusions 21 arranged on the inner wall of the runner 2 for changing the flow direction and the flow velocity of each part of the molten metal solution when the guide protrusions 21 are in contact with the molten metal solution, so that shearing friction force is generated inside the molten metal solution, and the molten metal solution can be semi-solidified with the cooling mechanism 4. Specifically, the special-shaped pipeline can be a structure having multiple sections crossed with each other to form a X-shape connection or in a left-and-right cross spiral mode; in this technical solution, the casting 5, the confluence chamber waste 51, the runner waste 52 and the sprue waste 53 after the semi-solid metal melt is cooled and formed are can be taken out of the die body 1; FIGS. 7, 8 and 9 show the shape of the waste material formed by adopting the special-shaped pipe structures with different shapes, the waste is the same as the runner 2 in shape, size and number.

(22) A semi-solid metal molding process utilizing the above die body, comprising the steps of:

(23) step 1, setting a teeming temperature according to different material components and the size and structure of a casting 5, and controlling the teeming temperature between high-limits of tolerances plus 20 C.40 C. of the liquid temperature and the solid temperature of the alloy material, for example, the liquid temperature of the A356 aluminum alloy being 615 C., and then the teeming temperature being 635 C.-655 C.;

(24) step 2, pushing the molten metal solution to a position close to the sprue 13 of the die body 1 through the pressure injection device at a low speed (i.e. the lowest pushing speed of the pressure injection device, typically 2 M/SEC), observing the surface and the molding condition of the casting 5, gradually increasing the speed, and then switching to high-speed injection (i.e. the highest pushing speed of the pressure injection device, typically 10 M/SEC), and finally pressurizing and injecting after the cavity 14 is filled with the semi-solid melt; and

(25) step 3, injecting cooling water into the spiral channel through an external condensed water circulation conveying device adopting a high-pressure adjustable flow rate water conveying mode to rapidly cool the runner 2 until the runner 2 is reduced to an ideal temperature (the temperature of the metal melt is an intermediate value of the sum of the liquid temperature and the solid temperature) so as to ensure that the liquid-solid ratio of each die is 50:50.

(26) It should be noted that in the process of die casting, a heat preservation barrel should be used as the die casting material barrel to reduce the heat loss; in addition, in the die casting process, the temperature of the die body 1 should be kept at 200-250 C. so as to avoid the defects of streaks, interlayers and the like.

(27) The working mechanism of the invention is as follows.

(28) When the molten metal, pushed into the runner 2 by the pressure injection equipment, flows in the runner 2, the molten metal flow may experience spiral centripetal friction in the runner 2, which, in combination with the dual influences of the pushing force of the pressure injection device and the friction of the inner wall of the runner 2, may result in a non-uniform flow rate of the molten metal at each bend in the runner 2, various flow states such as laminar flow, excessive flow, turbulent flow and the like are generated, so that frictional shearing force is generated inside the alloy melt and promotes the fracture of dendrite arms, reducing the grain size and spheroidizes the grains; meanwhile, semi-solid metal melt is generated under the temperature control of the cooling mechanism 4, and the semi-solid metal melt generated in the runner 2 can enter a cavity 14 in the die body 1 under the action of subsequent metal melt thrust, thus finally, molding of the casting 5 is finished.

(29) With the above technology adopted, it's not necessary to manufacture expensive slurrying equipment, so that the investment costs of the semi-solid metal molding technology can be reduced by ten thousand times compared with that of the prior art, and no influence factor of an oxide layer exists in the production process, the quality of the casting 5 will not be degraded due to cost reduction, on the contrary, the quality of the casting 5 can be further improved; in addition, in the pressure injection process, the raw materials are still molten metal, and the weight of the slurry is controllable, so that the amount of the residual waste in the runner 2 is controlled within an adjustable range; moreover, the casting process can be shortened, the slurrying and molding time can be shortened, the production efficiency can be effectively improved, and the costs can be further saved.

(30) The special-shaped pipeline runner die body provided by Example 1 and the straight runner die body in the prior art were taken to conduct a simulation of flowability test for the experimental die, wherein the length-width ratio of one end, communicated with the cavity, of the straight runner was 1:1.2n-1.5n and n refers to the number of the special-shaped pipeline runners in the special-shaped pipeline runner flowability test, and the width of one end, communicated with the cavity, of the straight runner was the same as the inner diameter of the special-shaped pipeline runner in the special-shaped pipeline runner flowability test.

(31) Specifically, the special-shaped pipeline runner was taken to conduct the simulation of flowability test for the experimental die, for example, the thrust of the pressure injection device was 13.2 MPA, the thickness of the casting was 2 mm, the actual weight was 52.4 g, the cross-sectional area of the special-shaped pipeline runner in a wavy shape was 82.93 mm2, the special-shaped pipeline runners were arranged in three rows, the linear distance between the two ends of the special-shaped pipeline runner was constantly 160 mm, and the distance between two adjacent wave crests of the special-shaped pipeline runner was 32 mm, and the distance between the adjacent wave crest and wave trough of the special-shaped pipe was 9 mm. It can be learned that the actual time to complete a die casting was 0.26548 s by using FLOW-3D simulation, and the total weight of the casting 5 and the returns in the runner was 460 g.

(32) The straight runner is used for the simulation of flowability test for the experimental die. The thrust of the pressure injection device was 13.2 MPA, the thickness of the casting was 2 mm, the actual weight was 52.4 g, the cross-section area of one end, communicated with the cavity, of the runner was 333.36 mm.sup.2, the cross-section area of one end communicated with the sprue was 541.84 mm2, the cross-sectional area of the straight runner was 437.6 mm.sup.2, and the length of the straight runner was 160 mm. It can be obtained by FLOW-3D simulation that the actual die casting completion time was 0.27515, and the total weight of the casting 5 and the waste in the straight runner was 503 g.

(33) It can be seen from the above-mentioned two simulation comparison structures that the material used in die casting by the semi-solid molding process is actually reduced by 43 g (runner returns) and the die casting time is shortened, and it can be seen from the simulation pictures that the metal flowability is better, with less slag inclusion and the gas inclusion.

(34) The above-mentioned examples are merely preferred embodiments of the present invention, and the scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions falling within the spirit of the present invention fall within the scope of the present invention. It should be noted that those skilled in the art will appreciate that various modifications and adaptations can be made without departing from the spirit and scope of the present invention.