JP4311971B2 - Mold for semi-solid metal compact - Google Patents

Description

【００２５】
用いた合金はＡＣ４ＣＨ合金である。合金組成はＡｌ−７％、Ｓｉ−０．３５％、Ｍｇ−０．１５Ｔｉである。半凝固金属６は、図１に示す製法で製造した。金型は２００℃に加熱し、黒鉛系の水溶性離型剤を塗布して、試験に用いた。
型締め力３１５ｔのマシンを使用し、約１．０ｋｇの半凝固金属９を圧縮変形した。
【００２６】
なお、半凝固金属の製造方法は、図１に示す方法に限定されるものではなく、種々の方法を適用できる。図１に示す方法は、半凝固金属を、治具を使用せずに、直接得る方法であって、液相線温度に対して過熱度を５０℃未満に保持された結晶微細化剤を含むアルミニウム合金溶湯、または、マグネシウム合金溶湯を冷却治具を使用することなく、直接、金属容器２に注湯し、溶湯内に結晶核を発生させ、該結晶核を成長させて、所定の液相率を示す成形温度まで冷却しつつ３０秒〜３０分間保持することにより、球状結晶を有する半凝固金属９を得ることを特徴としている。
【００２７】
半凝固金属６を金属容器２より反転して排出した後、下型８内に載置する。なお、半凝固金属６は、ＡＣ４ＣＨ合金に限定されるものでなく、半凝固金属６として準備できる金属または合金は、すべて本発明に適用できる。
【００２８】
また、本発明においては、冷却板に溶湯を接触させて、あるいは、冷却振動棒を、注湯する溶湯あるいは注湯後も継続して溶湯中に浸漬して、上記方法と同様に、保持容器内で冷却保持する方法も適用できる。さらに、一旦固化したビレットを加熱して製造した半溶融金属も本発明に適用できる。
【００２９】
比較例１０では、下型８に凹部がないため、半凝固金属６を載置して加圧した場合、下型８に接触して温度が低下し、発生した凝固層が半凝固金属成形体９の内部に混入するとともに、金属容器２内で生成した半凝固金属６の酸化物を固定できないために、該酸化物が、同様に、半凝固金属成形体９の内部に混入して、品質上問題があった。
【００３０】
比較例１１では、第１工程における型締め速度が遅いために、圧縮変形中にＳｉが濃縮されて成分偏析が発生し、また、変形速度が遅いために、圧縮成形の途中で、固相率が高まり成形し難くなり、収縮巣が発生した。
比較例１２では、第２工程における型締め速度が速いために、メタル集積部を設けていても、型外にメタルが飛散した。
【００３１】
比較例１３では、第１工程における型締め速度が速いために、メタル集積部を設けていても、型外にメタルが飛散した。
比較例１４では、固相率が低いために、メタル集積部を設けていても、型外にメタルが飛散した。また、収縮巣が発生しやすく、成分偏析も発生した。
比較例１５では、固体であるために、成形が容易でなく外観が悪化した。また、成形体９中に収縮巣が発生した。
比較例１６では、第１工程の後の変形停止時間が長すぎるために、半凝固金属成形体９の表面が固化して成形が容易でなくなり、外観が悪化した。
【００３２】
一方、実施例１〜９では、半凝固金属成形体９の内部組織に成分偏析は認められないし、また、凝固層、酸化物の混入も非常に少ない。また、加圧効果も十分に高いために、収縮巣もほとんど認められない。特に、突き出し治具１５、押出しピン１６を用いたものについては、さらに、収縮巣は観察されなかった。
また、メタル集積部を設けたものについては、第２工程の型締め速度が速くても、型外へのメタルの飛散はなかった。
【００３３】
【発明の効果】
以上、説明したことから明らかなように、本発明の半凝固金属成形体の成形金型は、上型に対し摺動可能で、局部加圧に加えて成形体の取りだし可能な治具を備えているので、鋳造作業、さらに、鋳造後の取り出し作業も能率よく行なうことができる。
【図面の簡単な説明】
【図１】溶湯から直接半凝固金属を製造するまでのプロセスを示す説明図である。
【図２】下型凹部の半凝固金属を上型が下降して圧縮して成形することを示す説明図である。
【図３】半凝固金属の型締め速度と変形率との関係を示す説明図である。
【図４】半凝固金属を加圧方向と異なる方向にスライド機構を有する鋳抜きピンにより、加圧または穴あけを行なうことを示す説明図である。
【図５】上型と下型の合わせ面および下型凹部のメタル集積部に半凝固金属の余剰メタルを集めることを示す説明図である。
【図６】上型に対して摺動可能な治具により局部加圧をし、成形後の半凝固金属成形体を取り出すことを示す説明図である。
【符号の説明】
１…ラドル
２…金属容器（保持容器）
３…溶湯
４…断熱材
５…エアー
６…半凝固金属
６Ａ…余剰メタル
６Ｂ…高周波誘導コイル
７…上型
８…下型
８Ａ…下型凹部
９…半凝固金属成形体
１０…鋳抜きピン
１１…スライド機構を有する鋳抜きピン
１２…半凝固金属集積部外
１３…半凝固金属集積部内
１４…下型凹部８Ａの半凝固金属集積部
１５…突き出し治具
１６…押出しピン[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a molding die for a semi-solid metal molded body, and in particular, a high-quality molded product by placing a semi-solid metal on a die and directly pressing it with an upper die or a pressure pin. The present invention relates to a molding die for a semi-solid metal molded body that can be molded.
[0002]
[Prior art]
Various high-pressure casting methods have been applied in order to obtain sound castings while advancing the weight reduction of automobiles from the viewpoint of global environmental protection and energy savings. ) Is attracting attention.
In forming a semi-solid metal, generally, a semi-solid metal produced by lowering the temperature from a liquid or a semi-molten metal produced by heating a solid state metal is once transferred to the sleeve, and then in the sleeve. The chip is moved, and a semi-solid metal or a semi-molten metal is pressed and filled into a molding die and molded.
[0003]
However, the molding method has several problems. First, when the semi-solid metal is inserted into the sleeve, the solid-liquid coexisting metal contacts the sleeve and loses heat, so that a solidified layer is easily formed. For this reason, the device which prevents that a solidified layer mixes in a product is needed.
Secondly, the ratio of the biscuit portion left in the sleeve during the filling of the semi-solid metal and the portion other than the product including the runner up to the product is high with respect to the total cast weight. In particular, when manufacturing a small product, the ratio becomes high. As a result, the product price increases.
[0004]
For this reason, a method of forming a semi-solid metal directly in a mold has been developed. However, in this method, the semi-solid metal placed on the lower mold is compressed and deformed as the upper mold approaches the lower mold, and the space formed by the upper mold and the lower mold is filled with the semi-solid metal. At this time, component segregation occurs in the molded product, the semi-solid metal is scattered outside the mold, or the semi-solid metal oxide generated in the upper part of the holding container is mixed in the product part. There is a problem.
[0005]
[Problems to be solved by the invention]
An object of the present invention is to provide a molding die for use in a method of pressure-forming a semi-solid metal without taking a complicated method, paying attention to the above problems.
[0006]
[Means for Solving the Problems]
In order to solve such a problem, according to the first aspect of the present invention, the semi-solid metal is filled in the space formed by the lower mold and the upper mold having a recess having a size capable of placing the semi-solid metal. a mold for molding a casting product and, on the die matching surface, Oite the surrounding and all around the space, provided with an integrated part of the space 1 or more sites for communicating with the semi-solid metal excess metal, A semi-solid metal surplus metal accumulation part is provided in a space composed of a lower mold depression and an upper mold depression facing it, and the accumulation part provided in the space is slidable with respect to the upper mold, and is locally A molding die for a semi-solid metal molded body having a structure in which a jig capable of taking out the molded body in addition to pressurization is provided.
[0007]
In a second invention mainly composed of the first invention, a half of a structure provided with a jig that is slidable with respect to the lower mold and has at least one function of local pressurization or removal of a molded body. A molding die for a solidified metal molded body is used.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, specific embodiments according to a molding die of a semi-solid metal molded body of the present invention will be described in detail with reference to the drawings.
[0010]
FIG. 1 is an explanatory view of a process from the molten metal directly to producing a semi-solid metal, and FIG. 2 is an explanatory view showing that the upper die descends and compresses and forms the semi-solid metal in the lower mold recess. FIG. 3 is an explanatory view showing the relationship between the mold clamping speed and the deformation rate of the semi-solid metal. FIG. 4 is a diagram showing how the semi-solid metal is pressed or cast by a cast pin having a slide mechanism in a direction different from the pressurizing direction. FIG. 5 is an explanatory diagram showing that drilling is performed, FIG. 5 is an explanatory diagram showing collecting surplus metal of semi-solid metal on the mating surface of the upper die and the lower die and the metal accumulation portion of the lower die recess, and FIG. It is explanatory drawing which shows taking out the semi-solid metal forming body after shaping | molding with the jig | tool which can be slid with respect to, and shape | molding.
[0011]
First, based on (1), (2), (3), and (4) of FIG. 1, the outline at the time of manufacturing a semi-solid metal will be described. In the figure, 1 is a ladle, 2 is a metal container (holding container), 3 is a molten metal, 4 is a heat insulating material, 5 is air, 6 is a semi-solid metal, and 6B is a high-frequency induction coil.
In the step (1), the molten metal 3 immediately above the melting point is poured into the metal container 2 to generate a large number of crystal nuclei in the molten metal. In the step (2), the spherical crystals are formed starting from the crystal nuclei while lowering the molten metal temperature. Growing to produce a semi-solid metal 6 having a target solid fraction.
[0012]
During this time, the upper and lower molten metal whose temperature tends to decrease is kept warm by the heat insulating material 4, and the portion not covered with the heat insulating material 4 is cooled by the air 5 to make the temperature of the semi-solid metal 6 in the container uniform. . In step (3), the semi-solid metal 6 is heated by the high-frequency induction coil 6B, and the temperature of the semi-solid metal 6 is further uniformed so that the semi-solid metal 6 can be easily discharged from the container. In step (4), the semi-solid metal 6 is discharged.
[0013]
The solid phase ratio of the semi-solid metal 6 is 30 to 99.9%. When the solid phase ratio is less than 30%, the metal is scattered out of the mold at the time of molding, and shrinkage cavities are likely to occur in the semi-solid metal 6. On the other hand, the solid phase ratio is 99.9%. If it exceeds, it becomes a solid state, forming becomes difficult, and the appearance of the semi-solid metal compact 9 is not good, so the solid phase ratio of the semi-solid metal 6 is set to 30 to 99.9%.
[0014]
Next, based on (1), (2), and (3) of FIG. 2, the outline at the time of manufacturing a semi-solid metal compact will be described. In the figure, 7 is an upper mold, 8 is a lower mold, and 9 is a semi-solid metal compact.
In the step (1), the semi-solid metal 6 obtained by the manufacturing method shown in FIG. 1 is inverted and placed on the lower die 8 having the recesses, and in the step (2), the upper die 7 is brought close to the lower die 8. Then, the semi-solid metal 6 is gently deformed, and in the step (3), the space formed by the upper die 7 and the lower die 8 is completely filled with the semi-solid metal 6, and the semi-solid metal compact 9 having the final shape is formed. Is molded.
That is, in the step (2), the semi-solid metal 6 is gently compressed and deformed to adjust the basic shape, and in the step (3), it is formed into a final product.
[0015]
When the semi-solid metal 6 is compressed and deformed by bringing the upper mold close to the lower mold, the mold clamping speed is set to 0.01 to 1.0 m / s during the compression deformation.
When the clamping speed is less than 0.01 m / s, it becomes difficult to accurately compress and deform the semi-solid metal 6, and component segregation occurs in the solidified structure of the semi-solid metal molded body 9, resulting in surface properties and characteristics. Since this causes unevenness, the lower limit of the mold clamping speed is set to 0.01 m / s.
On the other hand, if the mold clamping speed exceeds 1.0 m / s, the compression deformation is too fast and the semi-solid metal 6 may scatter from the gap between the upper mold and the lower mold. 0 m / s.
The mold clamping speed can be appropriately selected within the range of 0.01 to 1.0 m / s, preferably 0.01 to 0.6 m / s, more preferably 0.02 to 0.2 m / s. is there.
The mold clamping speed can be appropriately selected and changed within the range of 0.01 to 1.0 m / s even during the compression deformation of the semi-solid metal 6.
[0016]
As the first step, the basic shape is set by compressively deforming the semi-solid metal 6 at a clamping speed of less than 0.5 m / s until the deformation rate is less than 50% at maximum, and then, as the second step, the deformation rate. The final product shape can be formed by compressing and deforming at the mold clamping speed or higher.
The reason for changing the mold clamping speed at the deformation rate of 50% is that the basic shape can be easily adjusted in the range where the deformation rate is less than 50%. If the basic shape is set until the deformation rate exceeds 50%, the molten metal oozes out during compression deformation, or the semi-solid metal formed body 9 becomes too hard.
[0017]
Further, during the compressive deformation of the semi-solid metal 6, it may be held for less than 10 seconds after the end of the first step, once the mold clamping speed is set to less than 0.01 m / s, and then the second step may be performed. Specifically, between step (2) and step (3), once the mold clamping speed (deformation speed) is less than 0.01 m / s to reduce the solid phase rate of the product, the generation of shrinkage foci In the processing in the step (3), a method for partially expecting a forging effect including plastic processing can be adopted. In addition, during the compression deformation of the semi-solid metal 6, it can also vibrate in order to improve the internal quality of the molded body.
[0018]
FIG. 3 shows an example of the relationship between the mold clamping speed and the deformation rate of the semi-solid metal. In the case of type (a), in the first step, the mold clamping speed is deformed at a constant speed of 0.45 m / s at a deformation rate close to 50%, and then the mold clamping speed is increased to 0.95 m / s for deformation. Molding is performed until the rate reaches 90%. In the case of type (b), in the first step, the mold is clamped at a constant speed of 0.05 m / s until the deformation rate is close to 30%, and then the mold clamping speed is increased to 0.45 m / s. Thus, the molding is performed until the deformation rate reaches 80%.
[0019]
In actual molding, a pattern different from a fixed mold clamping speed can be selected for each deformation rate as shown in FIG.
The deformation rate (%) means a value obtained by subtracting the height H ₁ after deformation from the initial height H ₀ of the semi-solid metal 6 and dividing it by the initial height H ₀ . That is, it is a value calculated by the following formula.
Deformation rate (%) = 100 × (H ₀ −H ₁ ) ÷ H ₀
[0020]
FIG. 4 is an explanatory view showing that a semi-solid metal is pressurized or punched by a cast pin having a slide mechanism in a lateral direction different from the pressing direction of the semi-solid metal. In the figure, 6 is a semi-solid metal, 8 is a lower mold, 10 is a cast pin, and 11 is a cast pin having a slide mechanism. In the process of compressively deforming the semi-solid metal 6 or after the semi-solid metal 6 is compressed and deformed, the punching pin 11 having a slide mechanism is moved to press or punch the semi-solid metal 6. The semi-solid metal molded body 9 is formed.
[0021]
FIG. 5 is an explanatory view showing that the surplus metal of the semi-solid metal is collected on the mating surface of the upper die and the lower die and the metal accumulation portion of the lower die recess. In the figure, 7 is an upper mold, 8 is a lower mold, 8A is a lower mold recess, 9 is a semi-solid metal molded body, 12 is outside the semi-solid metal accumulation portion of the die-mating surface, and 13 is semi-solid metal accumulation of the die-mating surface. In the section, 14 is a semi-solid metal accumulation portion of the lower mold recess 8A.
As the upper mold 7 approaches the lower mold 8, the semi-solid metal 6 is compressed and deformed, and accordingly, the surplus metal 6 A of the semi-solid metal 6 placed in the lower mold recess 8 A is transferred to the semi-solid metal accumulation part 14. collected, and collect surplus metal 6A in the mating surface of the upper mold 7 and the lower die 8 and the semi-solid metal integrated unit out 12 in semi-solid metal stacking section 13.
[0022]
FIG. 6 is a view showing that the local pressurization is performed by a jig slidable with respect to the upper die, and that the semi-solid metal molded body 9 after the molding is taken out. In the figure, 7 is an upper mold, 8 is a lower mold, 15 is an extrusion jig, and 16 is an extrusion pin having a function of taking out a molded body.
A semi-solid metal molded body 9 manufactured through the process shown in FIG. 2 is pressed into a space formed by the upper mold 7 and the lower mold 8 by using a protruding jig 15. After the mold is opened by raising the upper mold 7, the semi-solid metal molded body 9 is first gripped by the robot arm, and then the semi-solid metal molded body 9 is lowered using the extrusion pin 16 and the extrusion jig 15. Stick out in the direction.
The semi-solid metal molded body 9 protruding downward is released from the upper mold 7 and conveyed to a desired place.
In the molding die shown in FIG. 6, although not shown, a jig that can slide with respect to the lower die and has at least one function of local pressurization or removal of the molded body may be provided. . Furthermore, a cast pin having a slide mechanism as shown in FIG. 4 may be provided in a direction different from the pressing direction.
[0023]
【Example】
(Example)
In the following, embodiments of the present invention will be described in detail with reference to the drawings and Table 1.
When the semi-solid metal 6 placed on the lower mold 8 is pressurized, the temperature of the semi-solid metal 6 decreases due to contact with the lower mold 8 to generate a solidified layer, and the solidified layer is mixed inside the product. In addition, the oxide generated in the metal container 2 and accumulated on the upper part of the semi-solid metal 6 may also be mixed in the product, resulting in a quality problem.
Further, when the semi-solid metal 6 is compressed and deformed, it is necessary to collect surplus metal more than the product weight at a predetermined location in the mold so as not to be scattered outside the mold. In addition, when the compression molding conditions are inappropriate during the compression deformation, component segregation may occur in the molded product, or the semi-solid metal 6 may be scattered during the molding process.
In this example, these were evaluated.
Table 1 shows the molding conditions and quality (evaluation results) of the semi-solid metal compact 9.
[0024]
[Table 1]

[0025]
The alloy used is an AC4CH alloy. The alloy composition is Al-7%, Si-0.35%, Mg-0.15Ti. Semi-solid metal 6 was manufactured by the manufacturing method shown in FIG. The mold was heated to 200 ° C., a graphite-based water-soluble release agent was applied, and used for the test.
Using a machine with a clamping force of 315 t, about 1.0 kg of the semi-solid metal 9 was compressed and deformed.
[0026]
In addition, the manufacturing method of a semi-solidified metal is not limited to the method shown in FIG. 1, A various method is applicable. The method shown in FIG. 1 is a method for directly obtaining a semi-solid metal without using a jig, and includes a crystal refining agent whose superheat degree is kept below 50 ° C. with respect to the liquidus temperature. A molten aluminum alloy or a molten magnesium alloy is poured directly into the metal container 2 without using a cooling jig, crystal nuclei are generated in the molten metal, the crystal nuclei are grown, and a predetermined liquid phase is obtained. A semi-solid metal 9 having a spherical crystal is obtained by holding for 30 seconds to 30 minutes while cooling to a molding temperature showing a rate.
[0027]
After the semi-solid metal 6 is inverted and discharged from the metal container 2, it is placed in the lower mold 8. The semi-solid metal 6 is not limited to the AC4CH alloy, and any metal or alloy that can be prepared as the semi-solid metal 6 can be applied to the present invention.
[0028]
Further, in the present invention, the holding container is made in the same manner as in the above method by bringing the molten metal into contact with the cooling plate or immersing the cooling vibration rod in the molten metal to be poured or continuously after the molten metal is poured. It is also possible to apply a method of cooling and holding inside. Furthermore, semi-molten metal produced by heating a billet once solidified can also be applied to the present invention.
[0029]
In Comparative Example 10, since the lower mold 8 has no recess, when the semi-solid metal 6 is placed and pressed, the temperature is lowered by contact with the lower mold 8 and the generated solid layer is a semi-solid metal molded body. 9 and the oxide of the semi-solid metal 6 produced in the metal container 2 cannot be fixed, so that the oxide is mixed into the semi-solid metal formed body 9 in the same manner. There was a problem above.
[0030]
In Comparative Example 11, since the mold clamping speed in the first step is slow, Si is concentrated during compression deformation, component segregation occurs, and since the deformation speed is slow, the solid phase ratio is reduced during compression molding. As a result, the mold became difficult to mold and a shrinkage nest was generated.
In Comparative Example 12, because the mold clamping speed in the second step was fast, the metal was scattered outside the mold even when the metal integrated portion was provided.
[0031]
In Comparative Example 13, since the mold clamping speed in the first step was fast, the metal was scattered outside the mold even when the metal integrated portion was provided.
In Comparative Example 14, since the solid phase ratio was low, the metal was scattered out of the mold even when the metal integrated portion was provided. In addition, shrinkage foci were likely to occur, and component segregation also occurred.
In Comparative Example 15, since it was solid, molding was not easy and the appearance deteriorated. Further, shrinkage nests occurred in the molded body 9.
In Comparative Example 16, since the deformation stop time after the first step was too long, the surface of the semi-solid metal formed body 9 was solidified and became difficult to form, and the appearance deteriorated.
[0032]
On the other hand, in Examples 1 to 9, no component segregation is observed in the internal structure of the semi-solid metal molded body 9, and the solidified layer and oxides are very little mixed. Further, since the pressurizing effect is sufficiently high, almost no contraction nest is observed. In particular, in the case of using the extrusion jig 15 and the extrusion pin 16, no shrinkage nest was observed.
Further, in the case where the metal accumulation part was provided, even if the mold clamping speed in the second step was high, the metal was not scattered outside the mold.
[0033]
【The invention's effect】
As is apparent from the above description, the molding die of the semi-solid metal molding of the present invention is slidable with respect to the upper die, and includes a jig capable of taking out the molding in addition to local pressure. Therefore, it is possible to efficiently perform the casting operation and further the removal operation after casting.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing a process from manufacturing a semi-solid metal directly from a molten metal.
FIG. 2 is an explanatory view showing that a semi-solid metal in a lower mold recess is molded by lowering and compressing an upper mold.
FIG. 3 is an explanatory view showing a relationship between a mold clamping speed and a deformation rate of a semi-solid metal.
FIG. 4 is an explanatory view showing that a semi-solid metal is pressed or drilled by a cast pin having a slide mechanism in a direction different from the pressing direction.
FIG. 5 is an explanatory diagram showing collecting surplus metal of a semi-solid metal on the mating surface of the upper die and the lower die and the metal accumulation portion of the lower die recess.
FIG. 6 is an explanatory view showing that a partial pressurization is performed by a jig slidable with respect to an upper mold, and a molded semi-solid metal formed body is taken out.
[Explanation of symbols]
1 ... Ladle 2 ... Metal container (holding container)
3 ... Molten metal 4 ... Heat insulating material 5 ... Air 6 ... Semi-solid metal 6A ... Excess metal 6B ... High frequency induction coil 7 ... Upper die 8 ... Lower die 8A ... Lower die recess 9 ... Semi-solid metal molded body 10 ... Cast pin 11 ····················································································································································· •

Claims (2)

A mold for forming a cast product by filling a space portion composed of a lower mold and an upper mold having a recess capable of placing a semi-solid metal, and filling the semi-solid metal with a space on the mold mating surface. surrounds the part and Oite the entire circumference, provided with a collecting section of the space and communicating with one portion or more semi-solid metal excess metal, in the space constituted by the recess of the upper mold facing thereto and a lower mold recess, A semi-solid metal surplus metal accumulation part was provided, and a jig that was slidable with respect to the upper mold and capable of taking out the compact in addition to local pressurization was provided in the accumulation part provided in the space part. A mold for semi-solid metal compacts.   The molding of the semi-solid metal molded body according to claim 1, further comprising a jig that is slidable with respect to the lower mold and has at least one function of local pressurization or removal of the molded body. Mold.

Images