EP0421039B1 - Procédé de moulage à mousse perdue et sous pression de pièces métalliques - Google Patents
Procédé de moulage à mousse perdue et sous pression de pièces métalliques Download PDFInfo
- Publication number
- EP0421039B1 EP0421039B1 EP89420446A EP89420446A EP0421039B1 EP 0421039 B1 EP0421039 B1 EP 0421039B1 EP 89420446 A EP89420446 A EP 89420446A EP 89420446 A EP89420446 A EP 89420446A EP 0421039 B1 EP0421039 B1 EP 0421039B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- metal
- mpa
- pressure
- mould
- value
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 29
- 239000002184 metal Substances 0.000 title claims abstract description 29
- 239000006260 foam Substances 0.000 title claims abstract description 9
- 238000005266 casting Methods 0.000 title abstract 2
- 238000000034 method Methods 0.000 claims abstract description 14
- 239000004576 sand Substances 0.000 claims description 8
- 229910045601 alloy Inorganic materials 0.000 claims description 6
- 239000000956 alloy Substances 0.000 claims description 6
- 229910052782 aluminium Inorganic materials 0.000 claims description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 2
- 239000004411 aluminium Substances 0.000 claims 1
- 239000011230 binding agent Substances 0.000 claims 1
- 238000010114 lost-foam casting Methods 0.000 claims 1
- 239000007788 liquid Substances 0.000 abstract description 3
- 229910000838 Al alloy Inorganic materials 0.000 abstract description 2
- 238000004519 manufacturing process Methods 0.000 abstract description 2
- 238000007711 solidification Methods 0.000 description 9
- 230000008023 solidification Effects 0.000 description 9
- 230000000694 effects Effects 0.000 description 6
- 239000000203 mixture Substances 0.000 description 4
- 238000000465 moulding Methods 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000010097 foam moulding Methods 0.000 description 2
- 238000005242 forging Methods 0.000 description 2
- 229910001338 liquidmetal Inorganic materials 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 238000001000 micrograph Methods 0.000 description 2
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical group [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000007767 bonding agent Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 210000001787 dendrite Anatomy 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 239000012778 molding material Substances 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920006327 polystyrene foam Polymers 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 239000011819 refractory material Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000001131 transforming effect Effects 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D18/00—Pressure casting; Vacuum casting
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/02—Sand moulds or like moulds for shaped castings
- B22C9/04—Use of lost patterns
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D27/00—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting
- B22D27/09—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting by using pressure
- B22D27/13—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting by using pressure making use of gas pressure
Definitions
- the present invention relates to a lost foam and pressure molding process for aluminum and aluminum alloy parts according to the preamble of claim 1.
- This request teaches that after filling the mold with the molten metal, that is to say when the model has been completely destroyed by the metal, that the vapors emitted by the foam have been evacuated, and preferably before as the solidification of the metal does not begin, an isostatic gas pressure is exerted on the whole of the mold and of the metal. This pressure is applied according to increasing values over time in order to avoid the phenomenon of watering and so that the maximum value is reached in less than 15 seconds.
- the molded parts obtained have an increased compactness which results in an improvement in the mechanical characteristics, in particular in terms of resistance.
- the document FR-A-2254387 describes a process for molding metals in which pressures between 2 and 25 MPa are applied, but this process applies to metals having a melting temperature above 1000 ° C. and n is not part of the lost foam molding.
- the present invention which consists of a lost foam and pressure molding process for aluminum parts and its alloys, in which an organic foam model of the part to be molded is immersed in a mold whose walls are delimited. by a dry sand bath containing no bonding agent, the mold is filled with the metal in the liquid state which replaces the foam and gradually solidifies and an increasing isostatic gas pressure is applied simultaneously to the mold and the metal at the earliest at the end of filling, characterized in that, in order to increase the fatigue life of said parts, the pressure exerted rises to a value between 1.5 and 10 MPa, a value which is reached before the amount of solidified metal exceeds 90% by weight.
- the invention consists in using pressures between 1.5 and 10 MPa and preferably between 5 and 10 MPa.
- the pressurization can be carried out using a sealed box in which the mold is placed, said box being equipped with one or more pipes distributed suitably on its wall and connected to a source of pressurized gas.
- the pressure is mainly used to accelerate the flow of liquid metal between the dendrites of the metal being solidified and the effect stops when the solid network has reached a certain development .
- these low pressures allow the counterweight to act effectively to avoid the phenomenon of shrinkage due to the contraction of the metal during solidification.
- Figure 1 attached is a micrograph of an alloy A-S7G03 molded according to the invention under a pressure of 7 MPa, then heat treated. This micrograph reveals the plastic deformation imposed on the dendritic network and which has the effect of filling the porosities, and illustrates well the forging effect to which the metal is subjected in this process.
- This new pressure range is preferably applied before the quantity of solidified metal reaches 40% by weight so as to be able to act on the liquid flow.
- the application of the pressure be made by progressive increase in particular at the start of solidification in order to avoid watering ", phenomenon which results from a transient imbalance between pressure exerted directly on the metal and the pressure exerted on the metal by means of the sand bath.
- the bath causes a relatively large pressure drop in the transmission of pressure and this results, at the level of the metal in contact with the sand, a tendency of this pressure to drive the metal through the grains of sand and to cause a deformation of the molded part.
- the invention can be illustrated using the following example of application: Cylindrical bodies with an outside diameter of 45mm, a wall thickness of 4mm, having adjacent ribs and bosses of 20x20x80mm were molded according to the prior process and that of the invention, that is to say applied inside the enclosure containing the mold and just before solidification begins, an isostatic gas pressure corresponding respectively to atmospheric pressure, 1 MPa, 5 MPa and 10 MPa.
- the fatigue life F in MPA was measured from tests in rotary bending on a test piece machined at 107 cycles according to the staircase method. F is valid for both thick and thin areas, since it does not depend on the speed of solidification but on the porosity and therefore on the pressure applied.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Manufacture Of Alloys Or Alloy Compounds (AREA)
- Casting Or Compression Moulding Of Plastics Or The Like (AREA)
- Powder Metallurgy (AREA)
- Forging (AREA)
- Moulds For Moulding Plastics Or The Like (AREA)
- Molds, Cores, And Manufacturing Methods Thereof (AREA)
- Measuring Fluid Pressure (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
- Continuous Casting (AREA)
- Blow-Moulding Or Thermoforming Of Plastics Or The Like (AREA)
- Mold Materials And Core Materials (AREA)
- Adhesives Or Adhesive Processes (AREA)
- Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
- Injection Moulding Of Plastics Or The Like (AREA)
- Treatments Of Macromolecular Shaped Articles (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR8911943A FR2651453B2 (fr) | 1989-09-07 | 1989-09-07 | Perfectionnement au procede de moulage a mousse perdue et sous pression de pieces metalliques. |
FR8911943 | 1989-09-07 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0421039A1 EP0421039A1 (fr) | 1991-04-10 |
EP0421039B1 true EP0421039B1 (fr) | 1993-07-14 |
Family
ID=9385393
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP89420446A Expired - Lifetime EP0421039B1 (fr) | 1989-09-07 | 1989-11-16 | Procédé de moulage à mousse perdue et sous pression de pièces métalliques |
Country Status (23)
Country | Link |
---|---|
EP (1) | EP0421039B1 (hu) |
JP (1) | JPH0626749B2 (hu) |
KR (1) | KR930002837B1 (hu) |
CN (1) | CN1017784B (hu) |
AT (1) | ATE91444T1 (hu) |
AU (1) | AU613541B2 (hu) |
BG (1) | BG92798A (hu) |
BR (1) | BR8906058A (hu) |
CA (1) | CA2001845C (hu) |
CS (1) | CS433890A3 (hu) |
DE (1) | DE68907601T2 (hu) |
DK (1) | DK581689A (hu) |
ES (1) | ES2042049T3 (hu) |
FI (1) | FI92162C (hu) |
FR (1) | FR2651453B2 (hu) |
HU (1) | HU209641B (hu) |
IE (1) | IE893715A1 (hu) |
MX (1) | MX170097B (hu) |
NO (1) | NO174187C (hu) |
PL (1) | PL286789A1 (hu) |
PT (1) | PT92353A (hu) |
RU (1) | RU1819185C (hu) |
YU (1) | YU47519B (hu) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19718725A1 (de) * | 1997-05-02 | 1998-11-05 | Schmidt & Co Gmbh Kranz | Verfahren zur Herstellung von wenigstens teilweise hohlen Metallartikeln |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100334977B1 (ko) * | 1997-03-18 | 2002-05-02 | 게오르그 휘쉐르 디사 아/에스 | 액티브 애프터-피딩 주조를 위한 방법, 압력공급 부재 및 압력공급 시스템 |
US7025109B1 (en) * | 2005-04-06 | 2006-04-11 | Gm Global Technology Operations, Inc. | Method and apparatus for controlling dispersion of molten metal in a mold cavity |
AT503391B1 (de) * | 2006-04-04 | 2008-10-15 | O St Feingussgesellschaft M B | Verfahren zum feingiessen von metallischen formteilen und vorrichtung hierfür |
CN101733387B (zh) * | 2010-01-21 | 2012-11-07 | 安徽中兴华汉机械有限公司 | 铝合金消失模的低压铸造方法 |
DE102012006572A1 (de) * | 2012-01-25 | 2013-07-25 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Verfahren zur Herstellung komplex geformter Gussteile mit einer Druckgießmaschine |
CN107206482A (zh) * | 2014-12-19 | 2017-09-26 | 梅纳德钢铁铸造公司 | 钢泡沫和用于制造钢泡沫的方法 |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR887120A (fr) * | 1941-11-19 | 1943-11-04 | Silumin Ges M B H | Procédé de moulage |
US3420291A (en) * | 1965-12-29 | 1969-01-07 | Trw Inc | Method for reducing metal casting porosity |
DE2358719A1 (de) * | 1973-11-26 | 1975-06-05 | Dso Metalurgia Rudodobiv | Verfahren und vorrichtung zum giessen von metallen und metall-legierungen |
GB1450066A (en) * | 1973-12-12 | 1976-09-22 | Dso Metallurg I Rudodobiv | Casting |
FR2606688B1 (fr) * | 1986-11-17 | 1989-09-08 | Pechiney Aluminium | Procede de moulage a mousse perdue de pieces metalliques |
ES2034726T3 (es) * | 1989-03-07 | 1993-04-01 | Aluminium Pechiney | Procedimiento de moldeo, con espuma perdida y bajo presion, de piezas metalicas. |
US5088544A (en) * | 1989-10-31 | 1992-02-18 | Aluminium Pechiney | Process for the lost-foam casting, under controlled pressure, of metal articles |
-
1989
- 1989-09-07 FR FR8911943A patent/FR2651453B2/fr not_active Expired - Lifetime
- 1989-10-31 CA CA002001845A patent/CA2001845C/fr not_active Expired - Lifetime
- 1989-11-09 MX MX018297A patent/MX170097B/es unknown
- 1989-11-16 EP EP89420446A patent/EP0421039B1/fr not_active Expired - Lifetime
- 1989-11-16 DE DE89420446T patent/DE68907601T2/de not_active Expired - Fee Related
- 1989-11-16 ES ES198989420446T patent/ES2042049T3/es not_active Expired - Lifetime
- 1989-11-16 AT AT89420446T patent/ATE91444T1/de not_active IP Right Cessation
- 1989-11-17 FI FI895506A patent/FI92162C/fi not_active IP Right Cessation
- 1989-11-20 DK DK581689A patent/DK581689A/da not_active Application Discontinuation
- 1989-11-20 PT PT92353A patent/PT92353A/pt not_active Application Discontinuation
- 1989-11-21 IE IE371589A patent/IE893715A1/en unknown
- 1989-11-21 AU AU45389/89A patent/AU613541B2/en not_active Expired
- 1989-11-29 RU SU894742535A patent/RU1819185C/ru active
- 1989-11-30 BR BR898906058A patent/BR8906058A/pt not_active Application Discontinuation
- 1989-12-08 KR KR1019890018168A patent/KR930002837B1/ko not_active IP Right Cessation
- 1989-12-20 NO NO895143A patent/NO174187C/no unknown
- 1989-12-28 JP JP1345126A patent/JPH0626749B2/ja not_active Expired - Fee Related
-
1990
- 1990-09-01 CN CN90108176A patent/CN1017784B/zh not_active Expired
- 1990-09-04 HU HU905776A patent/HU209641B/hu not_active IP Right Cessation
- 1990-09-05 YU YU168890A patent/YU47519B/sh unknown
- 1990-09-06 BG BG092798A patent/BG92798A/bg unknown
- 1990-09-06 CS CS904338A patent/CS433890A3/cs unknown
- 1990-09-07 PL PL28678990A patent/PL286789A1/xx unknown
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE19718725A1 (de) * | 1997-05-02 | 1998-11-05 | Schmidt & Co Gmbh Kranz | Verfahren zur Herstellung von wenigstens teilweise hohlen Metallartikeln |
Also Published As
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