DE102004006034B4 - Process for the formation and fine distribution of fine hydrogen bubbles in hydrogen-containing aluminum casting alloy melts - Google Patents
Process for the formation and fine distribution of fine hydrogen bubbles in hydrogen-containing aluminum casting alloy melts Download PDFInfo
- Publication number
- DE102004006034B4 DE102004006034B4 DE200410006034 DE102004006034A DE102004006034B4 DE 102004006034 B4 DE102004006034 B4 DE 102004006034B4 DE 200410006034 DE200410006034 DE 200410006034 DE 102004006034 A DE102004006034 A DE 102004006034A DE 102004006034 B4 DE102004006034 B4 DE 102004006034B4
- Authority
- DE
- Germany
- Prior art keywords
- hydrogen
- fine
- aluminum
- formation
- aluminum powder
- 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
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 title claims abstract description 29
- 229910052739 hydrogen Inorganic materials 0.000 title claims abstract description 27
- 239000001257 hydrogen Substances 0.000 title claims abstract description 27
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 title claims abstract description 25
- 238000005266 casting Methods 0.000 title claims abstract description 22
- 229910052782 aluminium Inorganic materials 0.000 title claims abstract description 18
- 238000000034 method Methods 0.000 title claims abstract description 9
- 230000015572 biosynthetic process Effects 0.000 title abstract description 17
- 239000000155 melt Substances 0.000 title abstract description 16
- 229910045601 alloy Inorganic materials 0.000 title abstract description 11
- 239000000956 alloy Substances 0.000 title abstract description 11
- 238000009826 distribution Methods 0.000 title abstract description 5
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims abstract description 11
- 229910052751 metal Inorganic materials 0.000 claims abstract description 10
- 239000002184 metal Substances 0.000 claims abstract description 10
- 239000002245 particle Substances 0.000 claims abstract description 10
- 229910052987 metal hydride Inorganic materials 0.000 claims abstract description 8
- 150000004681 metal hydrides Chemical class 0.000 claims abstract description 8
- 229910000838 Al alloy Inorganic materials 0.000 claims abstract description 5
- 229910000048 titanium hydride Inorganic materials 0.000 claims description 4
- 239000007787 solid Substances 0.000 claims description 2
- 239000003795 chemical substances by application Substances 0.000 abstract description 5
- 239000011148 porous material Substances 0.000 description 9
- 238000007711 solidification Methods 0.000 description 5
- 230000008023 solidification Effects 0.000 description 5
- 150000003839 salts Chemical class 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000005187 foaming Methods 0.000 description 3
- -1 titanium hydride Chemical compound 0.000 description 3
- 150000002431 hydrogen Chemical class 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000000465 moulding Methods 0.000 description 2
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 2
- 238000009827 uniform distribution Methods 0.000 description 2
- 206010063409 Acarodermatitis Diseases 0.000 description 1
- 239000004604 Blowing Agent Substances 0.000 description 1
- 241000447727 Scabies Species 0.000 description 1
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 238000002048 anodisation reaction Methods 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 239000003380 propellant Substances 0.000 description 1
- 208000005687 scabies Diseases 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D1/00—Treatment of fused masses in the ladle or the supply runners before casting
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D21/00—Casting non-ferrous metals or metallic compounds so far as their metallurgical properties are of importance for the casting procedure; Selection of compositions therefor
- B22D21/002—Castings of light metals
- B22D21/007—Castings of light metals with low melting point, e.g. Al 659 degrees C, Mg 650 degrees C
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C21/00—Alloys based on aluminium
- C22C21/06—Alloys based on aluminium with magnesium as the next major constituent
- C22C21/08—Alloys based on aluminium with magnesium as the next major constituent with silicon
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/04—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon
- C22F1/047—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon of alloys with magnesium as the next major constituent
Abstract
Verfahren zur Ausbildung und Feinverteilung feiner Wasserstoffbläschen in Form von Mikroporen in Wasserstoff enthaltenden Aluminium-Gusslegierungschmelzen,
wobei der Aluminium-Gusslegierungsschmelze ein Mittel zugeführt wird, das einen aus einem Aluminiumpulver mit einem Teilchendurchmesser kleiner 200 µm und einer natürlichen an Luft gebildeten Aluminiumoxidhaut hergestellten hochverdichteten Presskörper umfasst,
dadurch gekennzeichnet,
dass der Presskörper aus Aluminiumpulver 0,01 bis 1 Gew.-% Metallhydrid enthält, und
dass von dem Mittel weniger als 0,5 Gew.-% bezogen auf die Metallschmelze eingesetzt werden.Process for the formation and fine distribution of fine hydrogen bubbles in the form of micropores in hydrogen-containing cast aluminum alloy melts,
wherein the aluminum casting alloy melt is supplied with an agent comprising a high-density compact made of an aluminum powder having a particle diameter smaller than 200 μm and a natural alumina skin formed in air,
characterized,
that the aluminum powder compact contains from 0.01 to 1% by weight of metal hydride, and
that less than 0.5% by weight, based on the molten metal, of the agent is used.
Description
Die Erfindung befasst sich mit einem Verfahren zur Ausbildung und Feinverteilung feiner Wasserstoffbläschen in Form von Mikroporen in Wasserstoff enthaltenden Aluminium-Gusslegierungschmelzen, wobei der Aluminium-Gusslegierungsschmelze ein Mittel zugeführt wird, das einen aus einem Aluminiumpulver mit einem Teilchendurchmesser kleiner 200 µm und einer natürlichen an Luft gebildeten Aluminiumoxidhaut hergestellten hochverdichteten Presskörper umfasst.The This invention relates to a method of formation and dispersion fine hydrogen bubbles in the form of micropores in hydrogen-containing cast aluminum alloy melts, wherein the aluminum casting alloy melt is supplied with a means the one of an aluminum powder having a particle diameter less than 200 μm and a natural one comprises air-formed aluminum oxide skin produced high density compacts.
Aufgrund des Dichteunterschiedes von Aluminium-Gusslegierungen von der flüssigen und der festen Phase von ca. 2,4 auf ca. 2,7 g/m3 entstehen je nach der Nachspeisungsmöglichkeit bei der Herstellung von Gussstücken Hohlräume oder Lunker in den Gussstücken, die unerwünscht sind und bis zum Ausschuss dieser Teile führen. Bei der Weiterverarbeitung können Undichtigkeiten durch Abarbeiten entstehen, das Gussteil kann nicht druckdicht sein, Festigkeitsminderungen entstehen, die Eloxierbarkeit kann behindert sein. Jede Aluminium-Gusslegierung enthält unvermeidbar Wasserstoff, der die Neigung hat, sich bei bestimmten Temperaturen der Schmelze im Bereich der Erstarrung zu sammeln, so daß nach der Erstarrung der Schmelze an den Sammelstellen unerwünschte Hohlräume, Makrolunker und Einfallstellen gebildet werden.Due to the density difference of aluminum casting alloys of the liquid and the solid phase of about 2.4 to about 2.7 g / m 3 , depending on the Nachfüisungsmöglichkeit in the production of castings cavities or voids in the castings, which are undesirable and lead to the scrap of these parts. In the further processing leaks can occur by processing, the casting can not be pressure-tight, reduced strength, the anodization can be hindered. Each aluminum casting alloy inevitably contains hydrogen, which tends to collect at certain melt temperatures in the region of solidification, so that after solidification of the melt at the collection points undesirable voids, macro-shrinkage and sink marks are formed.
Es
ist bekannt, daß solche
Gussstücke
aus Aluminiumlegierungen, bei denen die Gefahr der Lunker- oder
Porenbildung besteht, mit Wasserstoff abgebenden Salzen oder Tabletten
begast werden, siehe z. B.
Aus
der
Bevorzugt wird das Aluminiumoxid in Gestalt feiner flockenartiger Teilchen mit einer Dicke weit unter 1 µm in die Schmelze, vorzugsweise mit einem mittleren Teilchendurchmesser von 30 bis 80 µm, eingebracht. Es ist möglich, den Wasserstoffgehalt der Gussteile in Abhängigkeit von der Menge des zugegebenen Aluminiumoxids einzustellen. Auf diese Weise ist es möglich, einen stabilen Dichteindex sowohl der Schmelze als auch der hieraus hergestellten Gussteile einzuhalten.Prefers the alumina is in the form of fine flake-like particles with a thickness far below 1 μm in the melt, preferably with an average particle diameter from 30 to 80 μm, brought in. It is possible, the hydrogen content of the castings as a function of the amount of to adjust added alumina. That's the way it is possible, a stable density index of both the melt and the resulting to comply with manufactured castings.
Es werden 0,1 bis 0,5 Gew.-% von gepresstem Aluminiumpulver, bezogen auf die Metallschmelze, der Schmelze zugegeben, um die Bildung von Einfallstellen und Makrolunkern bei gleichzeitiger Ausbildung von Mikrohohlräumen in feiner Verteilung in der erstarrten Schmelze zu verhindern.It are 0.1 to 0.5 wt .-% of pressed aluminum powder, based on the molten metal, the melt added to the formation of sink marks and macro-shrinkage with simultaneous formation of microvoids in to prevent fine distribution in the solidified melt.
Aus
der
Der Erfindung liegt die Aufgabe zugrunde, das Behandeln von Wasserstoff enthaltenden Aluminium-Gusslegierungen zwecks Ausbildung von Mikroporen weiter zu verbessern und effektiver zum machen, insbesondere die notwendige Menge des Mittels für einen gesicherten erfolgreichen Einsatz zu verringern.Of the Invention is based on the object, the treatment of hydrogen containing aluminum casting alloys for the formation of micropores continue to improve and make more effective, especially the necessary amount of agent for to reduce a secured successful deployment.
Überraschend hat sich herausgestellt, daß diese Aufgabe durch ein Verfahren gelöst wird, bei dem der Presskörper aus Aluminiumpulver 0,01 bis 1 Gew.-% Metallhydrid enthält, und bei dem von dem Mittel weniger als 0,5 Gew.-% bezogen auf die Metallschmelze eingesetzt werden. Bevorzugt wird erfindungsgemäß als Metallhydrid Titanhydrid eingesetzt.Surprised it turned out that this Task solved by a method is where the compact from aluminum powder containing 0.01 to 1 wt .-% metal hydride, and wherein the agent is less than 0.5 wt .-% based on the molten metal be used. According to the invention, titanium hydride is preferred as the metal hydride used.
Titanhydrid
ist bei 350°C
stabil und gibt dann seinen Wasserstoff ab. Dieser Wasserstoff verstärkt den
Effekt der Bildung von Mikroporen gewaltig, so daß man mit
wesentlich weniger Einsatzmaterial auskommt und die Anwendung sicherer
macht. Erfindungsgemäß werden
nun also in die zu behandelnde Schmelze nicht nur die „Keime" für die Bildung
von Wasserstoffporen eingegeben, sondern auch der Wasserstoff selbst.
Es hatte sich nämlich
gezeigt, daß bei
dem bekannten Mittel gem.
Die
Herstellung, Zugabe und Anwendung des erfindungsgemäßen Mittels
erfolgt wie in
Für die Arbeitsweise in der Gießereitechnik ist das verpresste Aluminiumpulver gemäß der Erfindung in Form einer Stange vorzuziehen, da eine solche Stange in einfacher Weise in einem Gießofen oder Schmelztiegel einführbar ist, wobei das Aluminiumpulver und das Metallhydrid zu einem Presskörper in Stangenform verdichtet sind, dessen Dichte mindestens 70% der Dichte von massivem Aluminium beträgt.For the way of working in foundry technology the compressed aluminum powder according to the invention in the form of a Rod, as such a rod in a simple manner in a casting furnace or Crucible insertable wherein the aluminum powder and the metal hydride are in a compact in Bar form are compacted, whose density is at least 70% of the density of solid aluminum.
Zur Ausbildung feiner Mikroporen genügt es, von dem Mittel weniger als 0,5 Gew.-%, vorzugsweise weniger als 0,25 Gew.-% bezogen auf die Metallschmelze einzusetzen, um die gewünschte Wirkung zu erzielen.to Training fine micropores is enough it is less than 0.5% by weight, preferably less as 0.25 wt .-% based on the molten metal to use the desired Effect.
Claims (3)
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE200410006034 DE102004006034B4 (en) | 2004-02-06 | 2004-02-06 | Process for the formation and fine distribution of fine hydrogen bubbles in hydrogen-containing aluminum casting alloy melts |
AT10562004A AT413703B (en) | 2004-02-06 | 2004-06-22 | Arrangement for forming and finely distributing fine hydrogen bubbles in aluminum cast alloy melts containing hydrogen comprises a pressed body made from aluminum body containing metal hydride |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE200410006034 DE102004006034B4 (en) | 2004-02-06 | 2004-02-06 | Process for the formation and fine distribution of fine hydrogen bubbles in hydrogen-containing aluminum casting alloy melts |
Publications (2)
Publication Number | Publication Date |
---|---|
DE102004006034A1 DE102004006034A1 (en) | 2005-08-25 |
DE102004006034B4 true DE102004006034B4 (en) | 2009-07-30 |
Family
ID=34801704
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
DE200410006034 Expired - Lifetime DE102004006034B4 (en) | 2004-02-06 | 2004-02-06 | Process for the formation and fine distribution of fine hydrogen bubbles in hydrogen-containing aluminum casting alloy melts |
Country Status (1)
Country | Link |
---|---|
DE (1) | DE102004006034B4 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN113637859B (en) * | 2021-08-11 | 2022-06-28 | 山东宏和轻量化科技有限公司 | Aluminum alloy and extrusion casting method and equipment thereof |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1023232B (en) * | 1956-10-26 | 1958-01-23 | Metallgesellschaft Ag | Process for the finishing of aluminum-silicon alloys |
AT225362B (en) * | 1959-01-05 | 1963-01-10 | Lor Corp | Process for the production of porous metal in one continuous operation |
DE1166421B (en) * | 1959-01-05 | 1964-03-26 | Lor Corp | Process for casting moldings |
US4417923A (en) * | 1981-09-14 | 1983-11-29 | Spolek Pro Chemickou A Hutni Vyrobu, Narodni Podnik | Solid refining agents for the refining of aluminum and alloys thereof and method of preparing said agents |
DE4325622C1 (en) * | 1993-07-30 | 1994-07-14 | Schaefer Chem Fab Gmbh | Processing molten aluminium casting alloy contg. hydrogen@ |
DE19717894A1 (en) * | 1996-05-02 | 1997-11-27 | Mepura Metallpulver | Porous metal especially aluminium matrix material production |
AT405946B (en) * | 1998-01-16 | 1999-12-27 | Illichmann Gmbh Leichtmetallgu | Process for producing a semi-finished powder metallurgy product |
DE19852277C2 (en) * | 1998-11-13 | 2000-12-14 | Schunk Sintermetalltechnik Gmb | Process for the production of a metallic composite material and semi-finished product for such |
DE19954755A1 (en) * | 1999-11-15 | 2001-05-17 | Schunk Sintermetalltechnik Gmb | Semi-finished metal product is foamed, e.g. to produce a lightweight sandwich construction material for traffic engineering, by heating in a chamber using external radiation |
-
2004
- 2004-02-06 DE DE200410006034 patent/DE102004006034B4/en not_active Expired - Lifetime
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1023232B (en) * | 1956-10-26 | 1958-01-23 | Metallgesellschaft Ag | Process for the finishing of aluminum-silicon alloys |
AT225362B (en) * | 1959-01-05 | 1963-01-10 | Lor Corp | Process for the production of porous metal in one continuous operation |
DE1166421B (en) * | 1959-01-05 | 1964-03-26 | Lor Corp | Process for casting moldings |
US4417923A (en) * | 1981-09-14 | 1983-11-29 | Spolek Pro Chemickou A Hutni Vyrobu, Narodni Podnik | Solid refining agents for the refining of aluminum and alloys thereof and method of preparing said agents |
DE4325622C1 (en) * | 1993-07-30 | 1994-07-14 | Schaefer Chem Fab Gmbh | Processing molten aluminium casting alloy contg. hydrogen@ |
DE19717894A1 (en) * | 1996-05-02 | 1997-11-27 | Mepura Metallpulver | Porous metal especially aluminium matrix material production |
AT405946B (en) * | 1998-01-16 | 1999-12-27 | Illichmann Gmbh Leichtmetallgu | Process for producing a semi-finished powder metallurgy product |
DE19852277C2 (en) * | 1998-11-13 | 2000-12-14 | Schunk Sintermetalltechnik Gmb | Process for the production of a metallic composite material and semi-finished product for such |
DE19954755A1 (en) * | 1999-11-15 | 2001-05-17 | Schunk Sintermetalltechnik Gmb | Semi-finished metal product is foamed, e.g. to produce a lightweight sandwich construction material for traffic engineering, by heating in a chamber using external radiation |
Also Published As
Publication number | Publication date |
---|---|
DE102004006034A1 (en) | 2005-08-25 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
OP8 | Request for examination as to paragraph 44 patent law | ||
8125 | Change of the main classification |
Ipc: B22D 21/04 AFI20051017BHDE |
|
8125 | Change of the main classification |
Ipc: C22C 1/08 AFI20060502BHDE |
|
8364 | No opposition during term of opposition | ||
R081 | Change of applicant/patentee |
Owner name: SCHAEFER METALLURGIE GMBH, DE Free format text: FORMER OWNER: SCHAEFER CHEMISCHE FABRIK GMBH, 53773 HENNEF, DE |
|
R082 | Change of representative |
Representative=s name: NEUMANN MUELLER OBERWALLENEY & PARTNER PATENTA, DE |
|
R071 | Expiry of right |