JP2009136888A - Semisolidified metal product molding die structure, method of molding semisolidified metal product, and semisolidified metal product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semisolidified metal product molding die structure that attains assured molding of a product with a complex configuration, such as a thin product with flange part, from a high-quality semisolidified metal at low cost, and also to provide a relevant molding method and a semisolidified metal product. <P>SOLUTION: The semisolidified metal product molding die structure includes a fixed lower die designed to mount the semisolidified metal on its upper surface side and a movable upper die capable of descending for pressurization toward the fixed lower die. Further, the structure includes a side die disposed on the side portion of the fixed lower die and adapted so as to form a product cavity together with the fixed lower die and the movable upper die. The side die is provided on the fixed lower die in a vertically slidable manner and is capable of ascending for pressurization with a force smaller than the descending pressurization force of the movable upper die. The compression of the upper die is started at a position where the side die is ascended, and the compression is maintained while defining the peripheral side portion of the product and then final molding is performed at the lowest position. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a molding die structure of a semi-solid metal product, a method of molding the semi-solid metal product, and a semi-solid metal product formed by the same, and more particularly, a semi-solid metal is placed on a die and directly press-molded. The present invention relates to a molding die structure of a solidified metal product, a method of molding a semisolid metal product, and a semisolid metal product molded by them.

Recently, by processing a metal billet with an aluminum alloy material or cooling a molten metal, processing in a semi-solid state (semi-molten) of about 540 ° C. to 650 ° C., for example, in a cooling curve in which a granular solid phase and a liquid phase coexist It is being adopted for various products in that it is excellent in shape retention as compared with processing from a molten state and at the same time is excellent in workability. On the other hand, for example, in the semi-solid (semi-molten) molding of an automobile wheel made of an aluminum alloy material, a semi-solid metal or a solid-state material produced by lowering the temperature from a liquid to a molding die is heated. There is known a molding method using a die casting machine in which a molten metal is once transferred to a sleeve, and then a semi-molten metal is filled in a mold for forming a product cavity, followed by pressure molding. However, in this method, the solid-liquid coexisting metal contacts the sleeve and is rapidly deprived of heat when inserted into the sleeve, so that a solidified layer is easily generated. In addition, rapid pressurization and filling to maintain fluidity causes air entrainment, which easily causes the solidified layer and the air layer to be mixed, and causes variations in mechanical properties. Moreover, the ratio with respect to the total casting weight of parts other than the product which added the runner to the product and the biscuit part left in the sleeve is high. As a result, there is a problem that the product price becomes high. On the other hand, the method of patent document 1 is proposed.

JP 2003-126955 A

In the method of Patent Document 1, as shown in FIGS. 18 to 20, a runner portion 114 and a compression portion 116 communicating with the cavity portion 112 are integrally provided in upper and lower molds 118 and 119 (FIG. 18 (1)). , (2)), placing the semi-solid metal 117 in the mold directly without forming the runner part or the compression part (FIGS. 19 (1), (2)), moving up and down to the upper mold 118 A possible second mold 132 or piston is installed, and partial pressurization is performed as required (FIGS. 20 (1) and (2)). However, in the method of FIG. 18, the semi-solid metal first comes into contact with the compression portion, and further, the metal flows into the cavity 112 via the biscuit portion 134 and the runner portion 114, so the metal rapidly Problems such as mixing of the solidified layer due to heat deprivation, variation in mechanical properties due to mixing of the air layer, and a high ratio of the non-product portion to the total casting weight, and increasing the product price still remain.

Further, according to the method of FIG. 19, as the upper die is lowered, the semi-solid material is deprived of heat by the die, and the fluidity is drastically lowered to solidify before obtaining a predetermined product shape. In addition, because the semi-solid metal billet is placed in the cavity and molded, the bottom surface of the semi-solid metal is easy to form a solidified layer at an early stage as a result of being placed on the lower mold upper surface and a good adhesion to stabilize. There are problems such as.

On the other hand, in the method of FIG. 20, the final molded product is thin and has a shape that is deeply squeezed at the center, and further has a complicated product shape having a projecting portion T directed laterally at the lower end. However, in the method of FIG. 20, the flow length at the time of compression of the semi-solid metal from the pressurizing part to the projecting part T is increased, the resistance is increased, and it is difficult to ensure a sufficient filling amount. There is a risk of forming defects due to minute internal defects and the like, and in reality, it is difficult to put a product having a complicated shape by forming such a semi-solid metal into practical use. In the case of FIGS. 18 and 19 as well, the same problem as in FIG. 20 described above may occur in a portion where the height in the vertical direction during product molding is large.

The present invention has been made in view of the above-described conventional problems, and its purpose is to be able to reliably form a product having a complicated shape such as a thin wall having a flange portion by molding a semi-solid metal, To provide a mold structure of a semi-solid metal product, a method for forming a semi-solid metal product, and a semi-solid metal product formed by the same, capable of obtaining a high-quality molded product and reducing material and manufacturing cost. It is in.

  In order to achieve the above object, the present invention includes a fixed lower mold 12 on which a semi-solid metal is placed on the upper surface side, a movable upper mold 14 that presses down toward the fixed lower mold, and a fixed lower mold 12. A side mold 16 which is disposed on the side and forms product cavities 22 and 60 together with a fixed lower mold 12 and a movable upper mold 14, and is provided so as to be slidable up and down with respect to the fixed lower mold 12. 14 and the side mold 16 that is pressed and raised by a force P2 smaller than the downward pressing force P1, and the molding mold structures 10-1 and 10-2 for semi-solid metal products. The molding die apparatus itself is made of a metal having heat resistance and wear resistance. The product molded with the molding die structure according to the present invention is rather unsuitable for molding a simple columnar object whose outer peripheral shape does not change up and down, and is a cylindrical product with a deep drawing, complicated in shape, particularly thin and deep in drawing. It is effective for molding a product, a product having a flange portion, or a product having a U-shaped concave portion facing the back on the left and right. For example, automobile wheels, hubs, mission cases, and the like can be mentioned, but any other metal product can be formed. The movable upper die performs compression of a semi-solid or semi-molten metal, and a normal press machine can be used in terms of ability. The side mold 16 ultimately defines a peripheral side portion of the semi-solid metal on the fixed lower mold, and therefore is provided so as to be movable up and down at least from the side of the fixed lower mold. It is done. The side mold 16 can be configured as a type that simply moves up and down from the peripheral side of the fixed lower mold. Further, the side mold 16 is divided into a plurality of split side sections by dividing the peripheral side portion of the product, and the split mold 50 type provided so that each split mold can slide and move forward and backward toward the compression start position. Can also be configured. The specific driving force generation mechanism of the movable upper type first driving device, the second driving device as the side type ascending pressure driving device, and the slide split type slide advance / retreat driving device (cylinder device) has an arbitrary structure. Can be used. The second driving device as the side-type rising press driving device is driven to be lifted by an upward pressing force smaller than the downward pressing force P1 of the movable upper die 14, thereby compressing the semi-solid metal on the lower die. While the force is applied, the movable upper die 14 and the side die are moved downward synchronously. Therefore, the pressure is lowered by falling to the downward pressure while maintaining a predetermined upward pressing force by a spring mechanism or other control. A mold raising and pressing drive is applied.

  At that time, the movable upper die that presses down at a position above the lower limit position L0 of the side die 16 that is pushed down with a force equivalent to the downward pressing force P1 of the movable upper die 14 that exceeds the upward pressing force P2 of the side die 16. The semi-solid metal 18 may be compressed by the side mold 16 and the fixed lower mold 12 that are pressed upward.

  Further, the height position of the side mold 16 at the start of compression of the semi-solid metal 18 placed on the fixed lower mold 12 is the volume V of the portion protruding from the main body Y of the product M including the ring wall Aw. The height position is determined by the correlation between the area S of the gap at the shortest distance length K between the fixed lower mold 12 and the inner part of the side mold 16 in the state in which the product cavities 22 and 60 are formed. Thus, the side mold 16 may be raised from the lower limit position L0 so that the flow path Pf of the semi-solid metal 18 is formed. When the side mold 16 starts to be pushed down after the compression by the movable upper mold 14 is started, specifically, the semi-solid metal 18 flows downward from the gap between the fixed lower mold 12 and the inner portion of the side mold 16. It may be at the same time as or after that.

  Further, the side mold 16 may include a plurality of slide split molds 50 (50A, 50B) that move laterally in a movable manner toward the compression start position of the semi-solid metal 18 by the movable upper mold 14.

  In addition, the present invention defines the fixed lower mold 12, the movable upper mold 14 that is pressed down toward the semi-solid metal 18 on the fixed lower mold, the side of the product M, and is provided so as to be movable up and down. Side mold 16 is prepared, and when the movable upper mold 14 is pressed down, the side mold 16 and the fixed lower mold 12 that serve as a flow path Pf of the semi-solid metal 18 placed on the fixed lower mold 12 are provided. The semi-solid metal 18 starts to be compressed by the movable upper die 14 at a position L1 where the side die 16 is pushed up so as to form a sufficient gap K therebetween, and then the raising pressure P2 of the side die 16 is increased. It is comprised from the shaping | molding method of the semi-solid metal product which shape | molds the semi-solid metal 18 by the downward | lower pressure P1 of the movable upper mold | type which surpasses.

  Moreover, this invention is comprised from the semi-solid metal product shape | molded using said shaping | molding method.

  According to the molding die structure of the semi-solid metal product of the present invention, a fixed lower die for placing the semi-solid metal on the upper surface side, a movable upper die that moves downwardly toward the fixed lower die, and a fixed lower die A side mold that is disposed on the side and forms a product cavity together with a fixed lower mold and a movable upper mold, and is slidable up and down with respect to the fixed lower mold and smaller than the downward pressing force of the movable upper mold This is a structure that includes a side mold that presses and lifts by force, so that it is a thin cylindrical product with a deep aperture, a product with protrusions in the radial direction, and a U-shape with the back facing left and right It is possible to concretely shape products with concave parts and other products that have complicated shapes and complicated mechanisms, and require a control device with semi-solid metal forming to ensure good formability. It is possible to manufacture with a simple configuration and low cost. In addition, compression molding of semi-solid metal enables molding with a relatively small press machine, which simplifies the equipment configuration, and ensures proper management of the amount of material required for casting, saving material costs and post-molding. It is possible to simplify the finishing process.

  In addition, the movable upper mold that is pressed down and the side mold that is pressed upward are positioned above the lower limit position of the side mold that is pushed down with a force equivalent to the downward pressing force of the movable upper mold that is superior to the upward pressing force of the side mold. And the fixed lower mold are used to compress semi-solid metal, while the movable upper mold is compression-molded, the side mold is lowered at the same time to make it closer to the product cavity shape. Since the molding is completed at the final molding pressure in a state where the is formed, good moldability can be secured without securing the flow path of the semi-solid metal and the deviation of the filling amount of the material or the molding pressure.

  In addition, the height position of the side mold at the start of compression of the semi-solid metal placed on the fixed lower mold is such that the volume of the part protruding from the main body of the product including the annular wall and the product cavity are formed. This is a height position where the correlation between the area of the gap at the shortest distance length between the fixed lower mold and the inner part of the side mold is determined as one element, and the side mold is raised from the descending limit position to the half By forming the flow path of the solidified metal, a flow path having a sufficient opening of the semi-solid metal is formed at the start of compression molding to extend from the annular wall portion of the product, the leg portion, or from them. High-quality molded products can be manufactured by filling the material evenly to every corner of the product such as the flange portion and applying a filling pressure. In addition, the volume of the part which protruded from the main-body part of the product containing an annular wall can also be made into a weight.

  In addition, the side mold has a structure including a plurality of slide split molds that move in the lateral direction so as to be movable back and forth toward the compression start position of the semi-solid metal by the movable upper mold. Even complex products that are difficult to die after completion can be reliably die-cut by lateral movement.

  Further, according to the method for forming a semi-solid metal product of the present invention, the fixed lower mold, the movable upper mold that presses and lowers toward the semi-solid metal on the fixed lower mold, the side portion of the product is defined, and A side mold provided so as to be movable up and down, and between the side mold and the fixed lower mold, which serve as a flow path for the semi-solid metal placed on the fixed lower mold when the movable upper mold is pressed down In order to form a sufficient gap, the compression of the semi-solid metal by the movable upper mold is started at the position where the side mold is pushed up, and then the movable upper mold is pressed down to overcome the upward pressing force of the side mold. Because it is a structure that forms a semi-solid metal by means of a thin cylindrical and deeply drawn cylindrical product, a product having protrusions in the radial direction thereof, and a product having U-shaped recesses facing the back on the left and right, Other products with complex shapes that require complicated mechanisms and control devices for molding are relatively easy. Do arrangement, it is possible to produce high-quality molded article at a low cost.

  The best mode for carrying out the present invention will be described below with reference to the accompanying drawings. 1 to 8 show a first embodiment of the present invention. The mold structure of the semi-solid metal product of the present embodiment shows an example in which the hub for a two-wheeled vehicle shown in FIG. As shown in FIG. 3, the product M has a main body Y having a flat unevenness on the upper surface side and a thin collar R on the outer edge, and a perpendicular direction from the base of the collar R on the back side of the main body Y. A projecting annular wall Aw and a cylindrical part N projecting perpendicularly from the central part are included. The annular wall Aw forms a side wall that is deeply squeezed so that the main body portion Y is the bottom, and has a so-called thin-walled deep-drawn type product shape.

  FIG. 1 is a longitudinal sectional view of a semi-solid metal product molding die structure 10-1 according to the first embodiment at a position immediately before the start of compression. In FIG. 1, the mold structure 10-1 for a semi-solid metal product of the present embodiment includes a fixed lower mold 12, a movable upper mold 14, and a side mold 16. A semi-solid metal 18 is placed on the fixed lower die 12, and the movable upper die 14 is pressed and moved downward from above so as to compress the placed semi-solid metal 18. The side mold 16 defines a peripheral side portion of a product when compression molding is performed, and the side mold 16 is provided so as to be movable up and down and is driven up by a predetermined pressing force. The upward pressing force of the side mold 16 is set to be much smaller than the downward pressing force of the movable upper mold 14. The semi-solid metal 18 placed on the fixed lower die 12 in a state where the side die 16 is raised to a predetermined height position is compressed by the lowering pressing force of the movable upper die 14 which exceeds the rising pressing force of the side die 16. Then, the side mold 16 is pushed down by the pressing force of the movable upper mold 14 to perform compression molding with the upper mold while changing the molding gap between the upper mold and the lower mold in the compression direction. To complete compression molding to complete the molding.

  Specifically, the molding die structure 10-1 of the present embodiment includes a movable upper die 14, a fixed lower die 12, an upper die, and a lower die that are driven by a drive device 20 such as a hydraulic press and are movable in a straight line. And a side mold 16 that defines a peripheral side portion of a product cavity 22 (see FIG. 5) formed in a mold closed state and is driven by a second driving device 24 and is movable in a straight line. The raising pressing force of the second driving device 24 is smaller than the lowering pressing force of the movable upper die 14, and the yielding open type drive that lowers the side die 16 by receiving the lowering pressing force to yield the raising force. For example, a bullet urging device such as a push spring, a jack device, or a combination thereof can be used. These drive devices 20 and 24 are driven while matching the timing based on the control of the control device 26 that performs sequence control of a work procedure (not shown) or program control by a storage device. 4 and 5, the illustration of the drive device and the control device is omitted.

  The semi-solid metal 18 to be placed on the fixed lower mold 12 is a metal having a characteristic of a semi-solid (semi-molten) state between a solidification start temperature and a solidification end temperature, and a semi-solid temperature range corresponding to each alloy composition. have. The semi-solid metal crystal spheroidizes with increasing temperature (decreasing the solid phase ratio) and gradually separates. In an aluminum alloy, when the solid phase ratio is 30% to 70%, the internal structure is a state in which spherical solid particles are suspended in the liquid phase. Can be obtained. Due to this property, in molding with a semi-solid metal, (a) since it is cast into a mold in a low-temperature semi-solid state, the amount of solidification shrinkage is reduced and the tendency to shrink is reduced. (B) The cooling rate is increased, a fine structure can be obtained, internal defects can be reduced, and a product excellent in mechanical properties can be manufactured. (C) Since casting is performed in a semi-solidified state, a uniform granular structure can be obtained. In the present embodiment, as shown in FIG. 1, the semi-solid metal material 18 before molding has, for example, a stepped flat disk shape or a cylindrical semi-molten metal having a maximum diameter at the tip of the inward convex portion of the side mold 16. Is placed on the fixed lower mold 12, and the movable upper mold 14 is pressed and compressed downward from above.

  More specifically, in FIG. 1, a fixed lower mold 12 is fixed on a lower mold base 28 fixed to a support base (not shown), and notches 30 corresponding to the cylindrical portion N and the ring wall Aw of the product M to be molded. It is installed with the mold shape forming 32 directed upward. On the other hand, there is provided a second drive device 24 comprising a jack device or the like that can be moved up and down from the lower side of the fixed lower die 12 and driven to yield free, and the side die 16 is supported by a pin 34 of this jack. It is movably provided in a vertical line.

The side mold 16 defines the peripheral side of the product, and has a vertical cylindrical shape and an inner peripheral contour size larger than the outer diameter of the fixed lower mold 12. The inner side of the side mold 16 is arranged so as to face the fixed lower mold 12. The outer periphery of the side mold 16 is notched in a tapered shape, and the upper mold support base 40 abuts against the notch 38 so that the side mold 16 is pushed down by the same pressing force as the movable upper mold 14. Move. The gap sandwiched between the inside of the side mold 16 and the fixed lower mold 12 constitutes a product cavity 22 when the upper and lower molds are closed, and becomes a flow path Pf during compression by the upper mold, and as the upper mold is compressed and lowered. It is a gap that changes its shape. Accordingly, the side mold 16 is a mold that forms a product shape corresponding to the outer edge portion of the fixed lower mold that is disposed in the vicinity of the outer edge of the fixed lower mold at the center and opposed to the side of the fixed lower mold.

An annular side mold base 36 is fixed to the upper portion of the jack pin 34 of the second driving device 24, and the side mold 16 is fixedly supported on the side mold base 36. The side mold base 36 is interposed between the second drive unit 24 and the side mold 16 and supports the side mold 16 when it is driven to rise with a lower pressing force than the lower pressing force of the movable upper mold. In addition, the lower limit of the side mold 16 is determined by hitting the lower mold base 28 during the lowering operation.

  A movable upper die 14 that is vertically opposed to the fixed lower die 12 is fixedly supported by an upper die support base 40. The upper die support base 40 is connected to a first drive device 20 such as a hydraulic press and is driven to move up and down. In particular, the upper die support base 40 is pressed downward when a semi-solid metal is compression-molded. The mold 14 moves up and down synchronously, and directly compresses the semi-solid metal during compression. Further, a pressing member 42 that is in contact with the notch 38 of the side mold 16 when being lowered is fixed to the upper mold support base 40. As a result, the movable upper die 14 descends to start compressing the semi-solid metal on the fixed lower die, and at the same time or thereafter, the holding member 42 presses the upper end side of the side die 16 with the same pressure, and the side die. Decrease 16 by overcoming its upward pressing force.

  The height position of the side mold 16 at the start of compression of the semi-solid metal 18 placed on the fixed lower mold 12 varies depending on the product shape, product thickness, ring wall height, product size, etc. Since the resistances are also different, it is difficult to determine them in general, and several empirical trial moldings are required. Among them, as an element for determining the molding start position height from the lower limit position of the side mold 16, the volume V of the part protruding from the main body Y of the product M including the annular wall Aw and the product cavity are formed. There is a correlation with the area S of the gap at the shortest distance length K between the fixed lower mold and the inner part of the side mold. The range where the fluidity from the gap of the semi-solid metal is most easily secured by the test molding is obtained in relation to the area S of the gap with the length K with respect to the protruding portion volume V. The molding start position height from the lower limit position L0 of the part die 16 can be determined. On the other hand, if the side mold 16 is raised at the start of compression, that is, if the vertical height position is too high and the area S is too large, the main body Y of the product on the upper side of the product at the time of molding is insufficiently filled or filled. The proper formability is impaired. Therefore, also in this respect, as described above, the volume V of the portion projecting from the main body portion Y of the product M including the annular wall Aw and the inner portion of the fixed lower die and the side die in the state where the product cavity is formed. The optimum range is obtained by test molding based on the correlation with the area S of the gap at the shortest distance length K. Then, as shown in FIG. 6, the side mold 16 is raised by the second driving device 24 so as to form an area S of the gap with the shortest distance length K between the fixed lower mold and the inner part of the side mold. Driven up to. In this state, a sufficient flow path 42 of the semi-solid metal in the semi-molten state is formed, and compression is started by the movable upper die. Further, the downward pressing force P1 of the movable upper die 14 by the first driving device 20 is much larger than the upward pressing force P2 of the side die 16 by the second driving device 24 (P1 >> P2) (for example, twice to About 10 times), the side mold 16 is pressed downward by the downward pressing force P1 to compress the upper mold 14 while defining the peripheral side part, and finally stops at the lower limit position L0 and applies the final pressure to compress. Complete.

  Next, the operation of this embodiment will be described. In forming the semi-solid metal, first, the side mold 16 is raised by driving the second driving device 24 and stopped. The raised position of the side mold 16 is fixed under a state in which the volume V of the portion protruding from the main body Y of the product M including the ring wall Aw and the product cavity are formed by empirical trial molding several times. The correlation with the area S of the gap at the shortest distance length K between the mold and the inner part of the side mold may be determined as an element. In this state, a semi-solid metal of a flat disk body made of a preform in a semi-molten state as shown in FIG. 1 is placed on the fixed lower mold 12. At this time, the peripheral side portion of the semi-solid metal 18 is defined by the inner peripheral wall surface of the side mold 16. In this state, since the gap (S) is formed between the side mold 16 and the fixed lower mold 12, this is a sufficient opening as a flow path for the semi-molten metal. From this state, when the movable upper die 14 is pressed down through the first driving device 20 and the semi-solid metal is compressed, the movable upper die 14 is compressed from the opening of the fixed lower die 12 and the inner portion of the side die 16 to smoothly circulate. Enter the wall Aw. On the other hand, when the first and second driving devices 20 and 24 are driven, the downward pressing force P1 of the movable upper die 14 is much larger than the upward pressing force P2 of the side die 16 (P1 >> P2) (for example, 10 Double pressure), the downward pressing force P1 overcomes the upward pressing force P2, and the side mold 16 is forcibly pressed down. During this depression, the semi-solid metal 18 is brought into pressure contact with the pressure surfaces of the movable upper die 14 and the fixed lower die 12, and the cross-sectional length is K, as in the state at the lowering position L2 in FIGS. Smoothly enters between the fixed lower mold 12 and the inner surface of the side mold 16 from the flow path Pf equal to. Even in the middle of this, the compression by the movable upper mold 14 continues to be maintained, and the distance between the lower end pressure surface of the movable upper mold 14 and the upper end pressure surface of the fixed lower mold 12 approaches with time. In this way, the change in the molding gap and the compression are performed simultaneously. Then, as shown in FIGS. 5 and 8, finally, the side mold base 36 comes into contact with the lower mold base 28 and stops. Uniform and uniform metal filling is performed to every corner of the product, and good moldability can be maintained.

  Next, with reference to FIG. 9 to FIG. 16, the mold structure 10-2 for a semi-solid metal product according to the second embodiment of the present invention will be described. Detailed description thereof is omitted.

  The mold structure 10-2 of the second embodiment is different from the first embodiment in that the side mold 16 includes a plurality of slide split molds 50A and 50B that horizontally move in the horizontal direction, and each of the slide split molds. Is connected to a cylinder device as a lateral drive device, and is driven to advance and retract toward the compression start position of the semi-solid metal 18 by the movable upper die 14, and after the molding is completed, the side die 16 is moved laterally. The mold can be opened.

  More specifically, as shown in FIG. 10, the side mold 16 includes two slide split molds 50A and 50B in which a half crack recess 51 of the product outer shape is formed on the side facing the semi-solid metal on the fixed lower mold. Each of these slide split dies 50A and 50B is connected and supported by a cylinder device 56. Then, the side mold base 54 fixed up to the upper end of the pin 52 is constituted by a thick plate member having a certain area, which is driven up and down by the four ascending pressing pins 52 of the jack of the second driving device. Further, two slide split dies 50A and 50B having a vertical cross section are driven to advance and retract toward the semi-solid metal 18 through the cylinder device 56 on the side die base 54. The two slide split dies 50A and 50B are placed on the side die base 54 so as to be slidable in the horizontal direction, and are guided to move on the side die base. For example, the cylinder device 56 is driven via a control device by a preset sequencer or program while taking timing together with the first and second drive devices 20 and 24. The slide split molds 50A and 50B are fixed to the drive rod 58 of the cylinder device, and the slide split mold and the cylinder device move up and down in synchronization with the vertical movement of the second drive device.

  In the second embodiment, the product to be molded has a flange F that protrudes further outward from the lower end of the ring wall Aw, as shown in FIG. In the case of such a complicated product shape, the flow length of the semi-solid metal product to the flange portion is further increased, and the resistance is greatly increased. However, good moldability can be obtained by setting the compression start position of the side mold as in the first embodiment, compression at the time of lowering, and final compression.

  In the second embodiment, similarly to the first embodiment, for example, a fixed lower mold and a side mold in a state in which the volume V of the part protruding from the main body Y of the product M including the annular wall Aw and the product cavity are formed. The semi-solid metal product preformed on the fixed lower die is stopped at the rising height position of the side die determined based on the correlation with the area S of the gap at the shortest distance length K from the inner portion of As shown in FIG. 10 arrow a, the slide split molds 50A and 50B are advanced toward the compression start position, and a start preparation state is set as shown in FIG. Note that, at this time, the side mold 16 is set to the ascending position from the optimum descending limit position as in the first embodiment. When a suitable and sufficiently large opening flow path Pf is obtained and the downward compression of the movable upper mold 14 is started, the product smoothly flows from the corresponding portion of the product to the annular wall Aw to the corresponding portion of the flange portion F (FIGS. 12 and 15). reference). Even in the middle of this, the movable upper die 14 continues to move toward the fixed lower die 12 by the downward pressing force of the movable upper die 14, and the compression action is maintained. At this time, the downward pressing force P1 of the movable upper die 14 is much larger than the upward pressing force P2 of the side die 16 (P1 >> P2) (for example, about 2 to 10 times), so the downward pressing force P1 is increased. The side die 16 is forcibly pushed down over the pressing force P2 to maintain the peripheral side portion regulation of the product. Then, as shown in FIGS. 13 and 16, the side mold base 54 finally comes into contact with the lower mold base 28 and stops, and in this state, sufficient pressure compression is performed to form the product cavity 60. Uniform and uniform metal filling is performed to every corner of the product, and good moldability can be maintained. Then, after the molding is completed, the movable upper mold 14 is lifted and separated, and the drive rod 58 of the cylinder device 56 is retracted to release the side mold 16 from the U-shaped product portion on the side of the product end. Can do. FIG. 17 is a view showing a displacement state due to a change with time of the position and pressure of the upper and lower molds in the molding structure of the second embodiment.

  Further, as a molding method using the semi-solid metal mold structure of the above-described embodiment, a fixed lower mold, a movable upper mold that is pressed down toward the semi-solid metal on the fixed lower mold, and a product A side mold that provides a flow path for a semi-solid metal placed on a fixed lower mold when the movable upper mold is pressed down is prepared by providing a side mold that defines the side section and is movable up and down. The compression of the semi-solid metal by the movable upper mold is started at the position where the side mold is pressed and raised so that a sufficient gap is formed between the upper mold and the fixed lower mold. A good molded product can be obtained by molding the semi-solid metal by the lowering pressing of the superior movable upper die.

  Next, an example of forming the semi-solid metal product of the present invention by the forming mold structure will be shown. Among the embodiments described above, the mold structure of the type having a plurality of split molds of the second embodiment is changed so that the rising position of the side mold is changed as the clearance L, and the semi-solid metal material to be charged is 2 kg and 4 kg. Each of 5 kg was molded and their molding status was compared.

Table 1 is formed using a semi-solid metal 18 of an AC4CH equivalent alloy and an AC2B equivalent alloy. The semi-solid metal used in Table 1 was a semi-solid metal material obtained by preforming a cylindrical material prepared by electromagnetic stirring. The cast product was formed into a drum shape by a slide mold 50 with a simplified shape assuming a hub of a motorcycle. The temperature of the mold used for the test is 220 ° C. to 290 ° C., and a mica-based water-soluble mold release agent having heat insulation is formed on the cavity surface formed by the upper and lower molds 14 and 12 and the side mold 16 before molding. Applied. When the pressure forming machine used was a semi-solid metal material 2 kg assuming a hub, the clamping force of the movable upper mold 14 was 500 tons, and the side mold ascending pressing force by the second driving device was 120 tons. In the case of a semi-solid metal material of 4.5 kg assuming a wheel, a clamping force of 1200 tons for the movable upper die 14 and an upward pressing force of 120 tons for the side die were used.

  In the molding example of Table 1, No. 1, No. 1 In the example of 5, since the molding is performed with the clearance L being 0, the side mold 16 is in the lowest lowered position and the space between the inside of the side mold and the fixed lower mold 12 is narrow, and the semi-solid metal 18 Since a sufficient flow cross-sectional area is not formed, the fluidity to the product flange F part formed through the gap between the fixed lower mold and the side mold during the molding is not ensured, both of which have a product shape molding defect. Occurred. No. 4, no. In the molding example 10, the side mold 16 is molded at a height position close to the movable upper mold 14 due to the upward pressing force of the side mold, the flow cross-sectional area of the semi-solid metal 18 is large, and the initial material flowability is For example, the fluidity up to the lower flange portion F during the downward molding in FIGS. 12 and 15 has been improved. It became an internal defect. No. 3, No. 7, no. In the molding example 8, the side mold 16 is held at an appropriate vertical height position by the upward pressing force of the side mold, the flow cross-sectional area of the semi-solid metal 18 is large, the initial material flowability and the middle of molding Fluidity between the movable lower mold and the side mold (thick part of the molded product) and the lower mold flange F is ensured, and further compression between the movable upper mold 14 and the fixed lower mold 12 is maintained. In addition, a sufficient pressure was applied to the inside with the final pressure with the side mold bottomed to the lowest position, and a product with good appearance and internal quality was obtained. This ensures good moldability by synchronous lowering movement with the upper mold of the side mold, molding void deformation, and compression molding at the same time, so that even complex shaped products can be reliably molded with semi-solid metal. Is confirmed to be possible.

It is a longitudinal cross-sectional view of the state just before the compression start which places the semi-solid metal of the metal mold | die structure of the semi-solid metal product which concerns on 1st Embodiment of this invention on a lower mold | type, and pressurizes an upper mold | type. It is an AA line arrow figure of FIG. It is a cross-sectional explanatory drawing of the product shape | molded using the metal mold | die structure of FIG. It is a cross-sectional explanatory drawing of the state in the middle of compression by the molding die structure of FIG. FIG. 3 is a cross-sectional explanatory view of the state of the lower limit position of the side mold in the molding die structure of FIG. 1. FIG. 3 is a half-longitudinal longitudinal section action explanatory diagram corresponding to the state of the molding die structure of FIG. 1. FIG. 5 is a half-longitudinal longitudinal section action explanatory diagram corresponding to the state of the molding die structure of FIG. 4. FIG. 6 is a half-longitudinal longitudinal section action explanatory diagram corresponding to the state of the molding die structure of FIG. 5. Compression that pressurizes the upper die by moving the side die of the mold structure of the semi-solid metal product according to the second embodiment of the present invention to the compression start position and placing the semi-solid metal on the lower die. It is a longitudinal cross-sectional view of the state immediately before the start. It is a BB line arrow figure of FIG. FIG. 10 is a cross-sectional explanatory view of a product molded using the mold structure of FIG. 9. FIG. 10 is a cross-sectional explanatory diagram of a state during compression by the molding die structure of FIG. 9. FIG. 10 is a cross-sectional explanatory diagram of the side mold in the lower limit position in the molding die structure of FIG. 9. FIG. 10 is a half-longitudinal longitudinal section action explanatory diagram corresponding to the state of the molding die structure of FIG. 9. FIG. 13 is an explanatory diagram of a semi-longitudinal longitudinal cross-section corresponding to the state of the molding die structure of FIG. 12. FIG. 14 is an explanatory diagram of a semi-longitudinal longitudinal cross-section corresponding to the state of the molding die structure of FIG. 13. FIG. 10 is a diagram showing a displacement state due to a change with time of the position and pressure of the upper and lower molds in the molding structure of FIG. 9. 1 shows a conventional semi-solid metal mold forming method. It shows another mold forming method of a conventional semi-solid metal. It shows another mold forming method of a conventional semi-solid metal.

Explanation of symbols

10-1, 10-2 Mold structure of semi-solid metal product 12 Fixed lower mold 14 Movable upper mold 16 Side mold 18 Semi-solid metal 20 First drive device 22 Product cavity 24 Second drive device 36 Side mold base 50 Slide split mold 52 Ascending pressing pin 54 Side mold base 56 Cylinder device 60 Product cavity M Product Y Body P1 Lowering pressing force of movable upper mold P2 Ascending pressing force of side mold Pf Metal flow path K Shortest distance length L1 Side mold rising height position corresponding to compression start position L2 Compression middle height position L0 Side mold lowering limit position

Claims (6)

A fixed lower mold for placing a semi-solid metal on the upper surface side;
A movable upper mold that presses down toward the fixed lower mold;
A side mold that is disposed on the side of the fixed lower mold to form a product cavity together with the fixed lower mold and the movable upper mold, and is provided so as to be slidable in the vertical direction with respect to the fixed lower mold. A mold structure for forming a semi-solid metal product, comprising: a side mold that presses and raises with a force smaller than the pressure.   The movable upper die that is pressed down and the side die that is pressed upward are fixed at a position above the lower limit position of the side die that is pushed down by a force equivalent to the downward pressing force of the movable upper die that exceeds the upward pressing force of the side die. 2. The mold structure of a semi-solid metal product according to claim 1, wherein the semi-solid metal is compressed by the lower mold. The height position of the side mold at the start of compression of the semi-solid metal placed on the fixed lower mold is
Correlation between the volume of the part protruding from the main body of the product including the ring wall and the area of the gap in the shortest distance length between the fixed lower mold and the inner part of the side mold in the state where the product cavity is formed is 1 3. A semi-solid metal product according to claim 1, wherein the metal mold is a height position determined as one element and is a position where the side mold is raised from the lower limit position to form a flow path of the semi-solid metal. Molding mold structure.   The side part mold includes a plurality of slide split molds that move laterally in a movable manner toward a compression start position of the semi-solid metal by the movable upper mold. Mold structure for semi-solid metal products. A fixed lower mold, a movable upper mold that presses and lowers toward the semi-solid metal on the fixed lower mold, and a side mold that regulates the side of the product and that can be moved up and down are prepared. ,
When the movable upper mold is pressed down, the side mold is pushed up so that a sufficient gap is formed between the side mold that becomes the flow path of the semi-solid metal placed on the fixed lower mold and the fixed lower mold. The semi-solid metal product is characterized in that compression of the semi-solid metal by the movable upper mold is started at the above position, and then the semi-solid metal is formed by the downward pressing of the movable upper mold that exceeds the upward pressing force of the side mold. Molding method. The semi-solid metal product shape | molded using the shaping | molding method of Claim 5.

Images