WO2001055464A1 - Procede de moulage sous pression et dispositif pour sa mise en oeuvre - Google Patents
Procede de moulage sous pression et dispositif pour sa mise en oeuvre Download PDFInfo
- Publication number
- WO2001055464A1 WO2001055464A1 PCT/EP2001/000029 EP0100029W WO0155464A1 WO 2001055464 A1 WO2001055464 A1 WO 2001055464A1 EP 0100029 W EP0100029 W EP 0100029W WO 0155464 A1 WO0155464 A1 WO 0155464A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- casting
- casting chamber
- chamber
- melt
- suspension
- Prior art date
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D17/00—Pressure die casting or injection die casting, i.e. casting in which the metal is forced into a mould under high pressure
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D17/00—Pressure die casting or injection die casting, i.e. casting in which the metal is forced into a mould under high pressure
- B22D17/007—Semi-solid pressure die casting
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/12—Making non-ferrous alloys by processing in a semi-solid state, e.g. holding the alloy in the solid-liquid phase
Definitions
- the invention relates to a die casting method for producing castings from a semi-solidified alloy melt, the alloy melt being brought into the semi-solidified state by stimulation of the crystallization process, introduced into a casting chamber and the castings being produced under pressure, and a device for carrying out the method.
- thermodynamic state of the metal plays a crucial role in the different machining processes.
- the associated effects can not only be used to facilitate the deformation process, but can also be used to significantly influence the morphology of the crystalline shapes and properties of the casting.
- the alloy loses its strength, which is of fundamental importance for the shaping process, and at the same time gains the ability for plastic formability as a structure-dependent property.
- the alloy melt is in the semi-solidified state. This condition is therefore referred to as a "metallic suspension", which is used as a raw material for new die casting processes.
- the invention is now concerned with the phenomenological behavior of the crystallizing liquids and their rheological properties and uses them to produce castings from the semi-solid state.
- a given melt volume is subjected to a special treatment before entering a casting chamber, the process being designed in such a way that the pre-metered metal can be fed into the die casting system without loss of quality.
- the semi-solid state can be influenced in its properties by various chemical-physical methods and by controlled heating or cooling.
- the starting material can be produced as a homogeneous metallic suspension and poured into the die casting system without loss of quality.
- a method for producing castings from the semi-solidified melt state is known from EP 0 841 406 AI. There, a multi-stage process is described, the aim of which is to produce the parts from the semi-rigid alloys in a vertical die casting machine.
- the transport of the raw material in the casting chamber is carried out after a Keimbil ⁇ up phase in the overheated melt followed by granulation.
- a vibration device was used for this is used to stimulate the appearance of germs in the crystallizing melt.
- the semi-rigid primary material was heated in a controlled manner. After the casting chamber was docked to the container for the primary material, this was pressed into the printing form.
- EP 0 733 421 A1 discloses a further casting method in which the casting chamber is filled with a casting plunger after the predetermined melt volume has been metered. The predetermined melt volume is brought into a suspension state by additional cooling and mixing in the electromagnetic field and then pressed into the die.
- the known method can improve the quality of the melt volume before pouring in, but it is not possible to keep the desired quality constant over a longer period of time. Rather, it was found that coarse structural deposits and associated low values of mechanical properties occur as a result of changes in the crystallization conditions in the melt.
- the inventors have now set themselves the task of achieving an improved structural homogeneity - compared with the products manufactured according to the prior art - the quantity of columnar crystals or transcrystallites produced and the quantity of coaxial or globulitic crystals being used as the quality standard ,
- the experimental results showed that the improved isotropy of the castings can be demonstrated by the type of crystalline shapes that occurred, and that in particular high strengths and very good toughness behavior can be demonstrated.
- the aim of the present invention is a die casting method which reliably ensures a homogeneous suspension state of the starting material. This primary material is then filled into a pressure chamber under pressure in this state. Another aim is that the primary material is produced from an exogenous metallic suspension.
- the die casting process developed by the present invention is intended to develop a continuous casting process, with all work stages being able to take place in a closed casting system. With the new die casting process, castings of excellent quality can be produced from the metallic suspension.
- the aforementioned objects are achieved with a method of the type mentioned in the introduction in that the predetermined melting volume outside the casting chamber in one closed processing container brought into rotation and a homogeneous metallic suspension of exogenous type is produced, from which a casting is made after filling in the casting chamber.
- the casting chamber always remains in the docked state and the entire process, which consists of individual work stages, is designed as a closed casting system.
- a particular distinguishing feature of the method according to the invention is the way in which the metallic suspension is prepared.
- the predetermined melting volume is brought into the suspension state by external cooling, which gives the suspension an endogenous character
- a fundamentally different technological approach was chosen in the present invention, according to which an exogenous metallic suspension suddenly occurs .
- the core of the approach is the rapid and even melt cooling, which is only possible by introducing additional micro-heat processes into the specified melt volume.
- a powder made from the same alloy as the melting volume is used as the coolant in order to achieve the necessary cooling effect in the shortest possible time To be able to reach time.
- the cooling effect consists of a decrease in the excess superheating temperature, with two parallel crystallization processes taking place:
- the melt is cooled from the inside to the predetermined temperature or at least the liquidus temperature and crystallization nuclei are generated by the additional cooling. These determine the structural morphology. Their uniform distribution in the resulting metallic suspension is of primary importance in order to ensure the same crystallization conditions in the entire suspension volume.
- the cooling powder is introduced into the melt under pressure, for which air, argon or nitrogen is used as a carrier gas.
- a special configuration of the processing container is required to produce metallic suspension after conditioning.
- this is a closed space, the outlet opening of which can be closed with a stuffing rod.
- the processing container is placed in an electromagnetic field and the filled melt is set in motion in this closed space and held there until the conditioning is complete.
- the movement of the melt leads to the appearance of a sheared material in the area of the solidification front, the melting of which in the liquid area stimulates the crystallization process. This broadens the range from the state of suspension.
- This suspension area is characteristic of the entire material volume in the proposed process. From the start, the forces acting on the molten metal due to the electromagnetic field are necessary to shear off the solidifying material in the narrow solidification area and to set the entire suspension volume in such a movement that the suspension maintains its ability to flow over a longer period of time and thereby achieving the homogeneity desired for the quality of the casting.
- the inventors have also succeeded in obtaining an experimental equation, after which the homogeneity of metallic suspensions is determined by a uniformity coefficient (X), the lower limit for efficient ⁇ aluminum alloys at the value 3.8 x 10 8 2 A / sec lies.
- X uniformity coefficient
- N the number of revolutions on the free surface of the partially fluid rotating body
- R the average wall thickness of the partially fluid rotating body.
- the special design of the processing container allows the predetermined melting volume to be placed under constant technological conditions in a metallic suspension, which leaves the container as a homogeneous suspension raw material through the outflow opening and then flows into the casting chamber.
- a particularly preferred embodiment of the invention is characterized by a transport chamber provided specifically for the suspension transport. This connects the processing container and the casting chamber, is equipped with a transport piston and can be attached to the vertically arranged casting chamber either at right or at an acute angle.
- the transport piston fulfills two functions:
- the piston is designed so that its frontal contour continues the inner contour of the casting chamber, so that there is no disturbance from the side of the transport piston in the filling opening area during the movement of the casting piston.
- the process in which the casting chamber is filled with the metallic suspension is characterized by a so-called "rising filling". As the casting chamber fills with the suspension, the casting piston is moved down (synchronously).
- Figure 1 is a schematic representation of a die casting device according to the invention, with which castings can be made from a homogeneous metallic suspension of an exogenous type.
- a processing container 1 is provided, which is equipped with a stuffing rod 2 and a pipe 3 for the introduction of cooling powder.
- the container is also connected to the holding furnace 5 by means of a melt line 4 and to the vertically arranged casting chamber 7 by a transport chamber 6.
- the processing container 1 is also inserted into an electromagnetic stirring device 8, which as an integrating system consists of an induction and control unit in the form of a closed component of the die casting machine.
- an electromagnetic stirring device 8 which as an integrating system consists of an induction and control unit in the form of a closed component of the die casting machine.
- the transport chamber 6 is in the acute angle mounted on the casting chamber 7.
- the casting chamber is aligned with a casting piston 11.
- An electromagnetic field is generated in the induction device with a control device (not shown on the diagram), which enables a stirring movement of the melt.
- the melt 12 reaches the processing container 1, which is located in the induction coil 8, by means of a melting line 4 from the holding furnace 5.
- the predetermined melting volume is set in motion in a closed space because the outflow opening of the processing container is sealed off with the stuffing rod 2.
- the melt flows onto the container walls and forms a liquid, hollow rotating body (according to the drawing, the rotating body has a conical shape). This creates a gravitational coefficient K on the free surface of the rotating body, the value of which is determined by the speed at which the different liquid layers move against each other.
- the entire melting volume can already be set in motion on this stage of the work, and not only on the solidification front.
- the entire melt volume is kept in this movement until the desired condition or suspension homogeneity is reached.
- a quantity of powder is introduced into the rotating melt via a powder metering device 3 (shown as a pipe in the diagram) which is sufficient to bring about a cooling effect.
- the cooling powder is introduced into the melt under pressure, specifically in a pulsating regime.
- the exogenous metallic suspension that suddenly occurs in processing container 1 is the result of three converging processes:
- the first process is part of the heat exchange process, in which the powder material extracts the excess heat from the overheated melt. Several cooled suspension areas arise, the temperature of which is below the liquidus level.
- the second process is related to the way in which the powder is introduced into the melt. Since this process takes place under pressure, the powder particles do not remain on the inner surface of the liquid rotating body, but penetrate deeply into the melt and act as efficient internal heat consumers, whereby an exogenous metallic suspension occurs simultaneously in the entire melt volume. Since the powder is introduced into the melt in a pulsating manner, elastic oscillations develop in the liquid metal, which stimulate the occurrence of new crystallization nuclei in the specified melt volume even more thanks to a microcavitation effect.
- the third process is the constant rotational movement of the given melting volume, which takes place during and parallel to the two operations already mentioned takes place.
- the advantageous embodiment of the method according to the invention makes it possible to keep the entire melting volume in motion in the closed space.
- a material is formed from the melt and then from the metallic suspension, which is the hollow rotating body.
- the gravitational coefficient that arises on its free surface is extremely important because it determines the homogeneity of the metallic suspension. The following parameters are affected:
- the processing container 1 is emptied of the suspension by the pull-out stuffing rod 2, which is received by the transport chamber 6.
- the suspension can either be set in rotation or flow directly out of the processing container 1, which has no influence on the suspension quality, but does influence the outflow time.
- the metallic suspension produced in this way has a large potential of kinetic energy, it flows very quickly towards the transport chamber 6 in the direction of the casting chamber 7, which it fills through the filling opening 10 provided.
- the injection piston 11 moves simultaneously with the influences such ⁇ sequent suspension synchronous downward to thereby enable the increasing filling operation.
- the transport chamber is equipped with the transport piston 9. After the filling process ends, the transport piston 9 is pushed forward and closes the filling opening 10 and thereby the casting chamber 7.
- the transport piston 9 is designed so that its front outline continues the inner outline of the casting chamber 7.
- the metallic suspension in the casting chamber fills the pressure chamber by means of piston acceleration, so that a casting is made from the semi-rigid starting material.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
- Extrusion Of Metal (AREA)
- Molds, Cores, And Manufacturing Methods Thereof (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
L'invention concerne un procédé de moulage sous pression pour la production de pièces moulées formées d'une masse fondue d'alliage semi-solidifiée, ladite masse fondue étant déplacée en l'état semi-solidifé en stimulant un processus de cristallisation, puis introduite dans une chambre de coulée, et les pièces moulées sont produites sous pression. On prépare tout d'abord une suspension métallique exogène en dehors de la chambre de coulée, dans une espace clos qui est en relation fonctionnelle avec la chambre de coulée et forme avec celle-ci une unité de coulée. La suspension métallique est mise en mouvement avant son admission dans la chambre de coulée ; il se forme alors un corps rotatif creux qui est maintenu en rotation jusqu'à ce qu'on obtienne une homogénéité de suspension pour la coulée. L'invention concerne en outre un dispositif pour la mise en oeuvre de ce procédé, caractérisé en ce qu'il comprend une chambre de coulée verticale comportant un piston de coulée et un récipient de traitement agencé à l'extérieur de la chambre de coulée, et en ce que le récipient de traitement est relié de façon rigide et fonctionnelle avec ladite chambre de coulée et forme avec celle-ci une unité de coulée.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2001554493A JP2003520683A (ja) | 2000-01-24 | 2001-01-04 | ダイカスト方法および該ダイカスト方法を実施するためのダイカスト装置 |
AU31661/01A AU3166101A (en) | 2000-01-24 | 2001-01-04 | Diecasting method and device for carrying out the same |
KR1020017012106A KR20010113858A (ko) | 2000-01-24 | 2001-01-04 | 다이 캐스팅 방법 및 장치 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE10002670A DE10002670C2 (de) | 2000-01-24 | 2000-01-24 | Druckgießverfahren und Vorrichtung zu seiner Durchführung |
DE10002670.2 | 2000-01-24 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2001055464A1 true WO2001055464A1 (fr) | 2001-08-02 |
Family
ID=7628380
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/EP2001/000029 WO2001055464A1 (fr) | 2000-01-24 | 2001-01-04 | Procede de moulage sous pression et dispositif pour sa mise en oeuvre |
Country Status (7)
Country | Link |
---|---|
US (1) | US20020179280A1 (fr) |
EP (1) | EP1120471A1 (fr) |
JP (1) | JP2003520683A (fr) |
KR (1) | KR20010113858A (fr) |
AU (1) | AU3166101A (fr) |
DE (1) | DE10002670C2 (fr) |
WO (1) | WO2001055464A1 (fr) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2003080883A1 (fr) * | 2002-03-19 | 2003-10-02 | Spx Corporation | Alliage d'aluminium |
JP2004025302A (ja) * | 2002-03-13 | 2004-01-29 | Evgenij Sterling | 鋳造過程用に合金溶湯を調製するための方法および装置 |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE10157349A1 (de) * | 2001-11-22 | 2003-06-12 | Demag Ergotech Gmbh | Vorrichtung und Verfahren zum Giessen von metallischen Materialien |
KR100578257B1 (ko) | 2003-06-03 | 2006-05-15 | 고동근 | 다이케스팅기 |
US20050103461A1 (en) * | 2003-11-19 | 2005-05-19 | Tht Presses, Inc. | Process for generating a semi-solid slurry |
KR100554093B1 (ko) * | 2004-02-04 | 2006-02-22 | 주식회사 나노캐스트코리아 | 반응고 성형장치 |
DE102005021891B4 (de) * | 2005-05-04 | 2011-12-22 | Evgenij Sterling | Verfahren zum Herstellen von Masseln und Massel |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6365015A (ja) * | 1986-09-05 | 1988-03-23 | Kubota Ltd | 金属溶湯への脱酸剤添加方法 |
JPH02274345A (ja) * | 1989-04-14 | 1990-11-08 | Nippon Steel Corp | 金属の鋳造方法 |
EP0733421A1 (fr) * | 1995-03-22 | 1996-09-25 | Hitachi Metals, Ltd. | Procédé de coulage sous pression |
JPH08290257A (ja) * | 1995-04-20 | 1996-11-05 | Mitsubishi Heavy Ind Ltd | 耐摩耗性アルミニウム合金鋳物及びその製造法 |
EP0841406A1 (fr) * | 1996-11-08 | 1998-05-13 | Ube Industries, Ltd. | Procédé pour mettre des métaux semi-solides en forme |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE69619847T2 (de) * | 1995-12-12 | 2002-11-07 | Thixomat, Inc. | Vorrichtung zum herstellen halbfester, thixotroper metallpasten |
EP1004374B1 (fr) * | 1998-11-25 | 2002-02-13 | Ritter Aluminium Giesserei Gmbh | Procédé et dispositief de coulée sous pression pour la fabrication de pièces coulées en alliages avec propriétés thixotropes |
DE19918229C2 (de) * | 1999-04-22 | 2002-07-18 | Daimler Chrysler Ag | Verfahren zum Herstellen von Rohlingen für Zylinderlaufbüchsen |
-
2000
- 2000-01-24 DE DE10002670A patent/DE10002670C2/de not_active Expired - Fee Related
-
2001
- 2001-01-04 US US09/937,281 patent/US20020179280A1/en not_active Abandoned
- 2001-01-04 KR KR1020017012106A patent/KR20010113858A/ko not_active Application Discontinuation
- 2001-01-04 WO PCT/EP2001/000029 patent/WO2001055464A1/fr active Application Filing
- 2001-01-04 JP JP2001554493A patent/JP2003520683A/ja active Pending
- 2001-01-04 AU AU31661/01A patent/AU3166101A/en not_active Abandoned
- 2001-01-04 EP EP01100291A patent/EP1120471A1/fr not_active Withdrawn
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6365015A (ja) * | 1986-09-05 | 1988-03-23 | Kubota Ltd | 金属溶湯への脱酸剤添加方法 |
JPH02274345A (ja) * | 1989-04-14 | 1990-11-08 | Nippon Steel Corp | 金属の鋳造方法 |
EP0733421A1 (fr) * | 1995-03-22 | 1996-09-25 | Hitachi Metals, Ltd. | Procédé de coulage sous pression |
JPH08290257A (ja) * | 1995-04-20 | 1996-11-05 | Mitsubishi Heavy Ind Ltd | 耐摩耗性アルミニウム合金鋳物及びその製造法 |
EP0841406A1 (fr) * | 1996-11-08 | 1998-05-13 | Ube Industries, Ltd. | Procédé pour mettre des métaux semi-solides en forme |
Non-Patent Citations (3)
Title |
---|
PATENT ABSTRACTS OF JAPAN vol. 012, no. 297 (C - 519) 12 August 1988 (1988-08-12) * |
PATENT ABSTRACTS OF JAPAN vol. 015, no. 032 (M - 1073) 25 January 1991 (1991-01-25) * |
PATENT ABSTRACTS OF JAPAN vol. 1997, no. 03 31 March 1997 (1997-03-31) * |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2004025302A (ja) * | 2002-03-13 | 2004-01-29 | Evgenij Sterling | 鋳造過程用に合金溶湯を調製するための方法および装置 |
AU2003200990B2 (en) * | 2002-03-13 | 2008-05-22 | Evgenij Sterling | Process and device for preparing a melt of an alloy for a casting process |
JP4541650B2 (ja) * | 2002-03-13 | 2010-09-08 | スターリング エフゲニー | 鋳造過程用に合金溶湯を調製するための方法および装置 |
KR100995490B1 (ko) * | 2002-03-13 | 2010-11-19 | 에브게니즈 슈테링 | 주조과정을 위한 합금 용융물 처리 방법 및 장치 |
WO2003080883A1 (fr) * | 2002-03-19 | 2003-10-02 | Spx Corporation | Alliage d'aluminium |
Also Published As
Publication number | Publication date |
---|---|
AU3166101A (en) | 2001-08-07 |
EP1120471A1 (fr) | 2001-08-01 |
JP2003520683A (ja) | 2003-07-08 |
DE10002670C2 (de) | 2003-03-20 |
US20020179280A1 (en) | 2002-12-05 |
KR20010113858A (ko) | 2001-12-28 |
DE10002670A1 (de) | 2001-08-02 |
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