US20030075020A1 - Method for producing an aluminum-titanium-boron prealloy for use as a grain refiner - Google Patents
Method for producing an aluminum-titanium-boron prealloy for use as a grain refiner Download PDFInfo
- Publication number
- US20030075020A1 US20030075020A1 US10/148,659 US14865902A US2003075020A1 US 20030075020 A1 US20030075020 A1 US 20030075020A1 US 14865902 A US14865902 A US 14865902A US 2003075020 A1 US2003075020 A1 US 2003075020A1
- Authority
- US
- United States
- Prior art keywords
- alloy
- melt
- process according
- particles
- tib
- 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.)
- Abandoned
Links
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 14
- -1 aluminum-titanium-boron Chemical compound 0.000 title claims abstract description 4
- 238000000034 method Methods 0.000 claims abstract description 35
- 239000002245 particle Substances 0.000 claims abstract description 31
- QYEXBYZXHDUPRC-UHFFFAOYSA-N B#[Ti]#B Chemical compound B#[Ti]#B QYEXBYZXHDUPRC-UHFFFAOYSA-N 0.000 claims abstract description 26
- 229910033181 TiB2 Inorganic materials 0.000 claims abstract description 26
- 239000000155 melt Substances 0.000 claims abstract description 21
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 18
- 238000001816 cooling Methods 0.000 claims abstract description 16
- 229910052796 boron Inorganic materials 0.000 claims abstract description 12
- 229910000838 Al alloy Inorganic materials 0.000 claims abstract description 8
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 5
- 239000011248 coating agent Substances 0.000 claims abstract description 5
- 238000000576 coating method Methods 0.000 claims abstract description 5
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 4
- 229910045601 alloy Inorganic materials 0.000 claims description 43
- 239000000956 alloy Substances 0.000 claims description 43
- 239000010936 titanium Substances 0.000 claims description 39
- 230000008569 process Effects 0.000 claims description 32
- 230000015572 biosynthetic process Effects 0.000 claims description 9
- 239000000274 aluminium melt Substances 0.000 claims description 8
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 6
- 239000000203 mixture Substances 0.000 claims description 6
- 239000002994 raw material Substances 0.000 claims description 4
- 239000004411 aluminium Substances 0.000 claims description 3
- 238000003756 stirring Methods 0.000 claims description 3
- 238000009749 continuous casting Methods 0.000 claims description 2
- 239000007858 starting material Substances 0.000 abstract 1
- 239000000463 material Substances 0.000 description 6
- 238000005266 casting Methods 0.000 description 5
- 239000007795 chemical reaction product Substances 0.000 description 5
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 4
- 150000003839 salts Chemical class 0.000 description 4
- 230000006911 nucleation Effects 0.000 description 3
- 238000005096 rolling process Methods 0.000 description 3
- 229910018575 Al—Ti Inorganic materials 0.000 description 2
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 2
- 230000009471 action Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000001125 extrusion Methods 0.000 description 2
- 230000006698 induction Effects 0.000 description 2
- 238000010899 nucleation Methods 0.000 description 2
- 238000007670 refining Methods 0.000 description 2
- 239000002893 slag Substances 0.000 description 2
- 238000009210 therapy by ultrasound Methods 0.000 description 2
- 238000002604 ultrasonography Methods 0.000 description 2
- 229910020491 K2TiF6 Inorganic materials 0.000 description 1
- 229910020261 KBF4 Inorganic materials 0.000 description 1
- 229910000905 alloy phase Inorganic materials 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000003292 diminished effect Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000010907 mechanical stirring Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000003303 reheating Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 239000011780 sodium chloride Substances 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
Images
Classifications
-
- 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
- C22C1/02—Making non-ferrous alloys by melting
- C22C1/026—Alloys based on aluminium
-
- 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
- C22C1/02—Making non-ferrous alloys by melting
- C22C1/03—Making non-ferrous alloys by melting using master alloys
Definitions
- This invention concerns a process for the manufacture of a grain refinement medium on the basis of an aluminium-titanium-boron pre-alloy through the introduction of raw materials containing Ti and B into an aluminium melt under formation of TiB 2 particles and the solidifying of this pre-alloy melt.
- EP-A-0396389 describes a process for the continuous manufacture of an Al—Ti—B grain refinement alloy, in which raw materials containing Ti and B are introduced into a reaction zone of an aluminium melt, whereby the melt is agitated in the reaction zone. A mixture of the formed alloy together with the reaction products is supplied continuously to a refining zone in which the slag with the reaction products is continuously collected on the surface of the melt and removed. The formed grain refinement alloy is continuously passed from the refining station to a casting station, in which the melt is continuously cast into a strand.
- the cast strand can either have the desired strand or wire width directly, or it can be worked through further treatment by way of rolling or extrusion molding into the desired grain refinement material.
- TiB 2 particles in the Al—Ti—B grain refinement media known today are highly susceptible to the formation of agglomerates. The result is a diminished effect of the grain refinement medium. Further disadvantages arise through agglomerates and inclusions which can lead to faults in the end product. Examples of this are grey lines, holes, material separation and stringers.
- agglomerates occur preferably on low melt salts such as for example KF and NaCl and on oxide skins and can spread further as a result. Such agglomerates are “soft”, and can be forced through filters and as such reach the cast strand.
- the invention is therefore based on the task of preparing a process for the manufacture of an Al—Ti—B grain refinement medium, with which the formation of agglomerates of TiB 2 particles can be largely prevented and existing agglomerates can be deagglomerated.
- the task is resolved with a process of the type described initially, whereby the pre-alloy is set in motion between the liquidus temperature of the Al 3 Ti phase and the solidus temperature of the pre-alloy for a sufficient time period for the dispersal of the TiB 2 particles in the melt, and at the same time the pre-alloy is cooled at a first cooling rate so that the TiB 2 particles act as nuclei for the Al 3 Ti phase occurring below the liquidus temperature and the surface of the TiB 2 particles are at least partly covered with a coating of Al 3 Ti, and in that the pre-alloy is then cooled below the solidus temperature of the alloy at a second cooling rate higher than the first cooling rate.
- the term “motion of the melt” refers to all process steps intended to largely eliminate the formation of agglomerates of TiB 2 particles and deagglomerate existing agglomerates. These include among others mechanical stirring and vibration processes at high revolutions of the agitator and the production of cavitations, i.e. the formation of bubbles, the implosion of which causes shock waves which lead to the deagglomeration of agglomerated particles. Included in the latter process are for example the ultrasound treatment and vibration by means of a magneto-hydrodynamic resonator.
- the grain refinement medium manufactured with the process in accordance with this invention causes, especially in the case of grain refinement of casting formats from aluminium alloys, an improved and more homogenous action of the grain refinement medium by way of a more homogenous distribution of the individual TiB 2 particles, a better coating of the TiB 2 particles with Al 3 Ti phase and a reduction or dispersal of any salts and oxide inclusions remaining in the grain refinement medium.
- the pre-alloy will already be set in motion before the temperature falls below the liquidus temperature of the Al 3 Ti phase.
- the action of the grain refinement medium manufactured in accordance with the invention is shown in the fact that as a result of coating formed from a thin Al 3 Ti layer, the individual TiB 2 particles, which are roughly 0.5 to 5 ⁇ m wide, show an excellent nucleation action and the particles act in isolation and not as agglomerates, so that a comparable grain refinement can be achieved with a considerably smaller amount of grain refinement medium than with a grain refinement medium according to the state of the art. In practice, this means that the grain refinement medium can be manufactured in a considerably more diluted form, which further reduces the tendency of the TiB 2 particles to form agglomerates.
- the movement of the melt occurs by way of sound, preferably ultrasound, where the melt is suitably exposed to sound frequencies of 50 Hz to 50 kHz, preferably at least 10 to 30 kHz.
- the second cooling rate is preferably more than 1° C./sec, especially more than 5° C./sec, and notably preferably more than 10° C./sec.
- the pre-alloy melt can be cast into any format.
- a strand suitably manufactured continuously by way of vertical or horizontal casting This strand can either be cast already in the format of the rod or wire material desired as grain refinement medium or can be worked further by way of rolling or pressing into the rod or wire material.
- Vertically cast large strands especially are further worked by extrusion molding.
- the horizontal continuous casting of formats with relatively small diameter is preferred as this process allows continuous production.
- the horizontally extruded casting formats are further worked preferably through rolling to the desired rod or wire material.
- a pre-alloy manufactured with the process in accordance with this invention has a composition, the total titanium content of which exceeds the stoichiometric ratio of TiB 2 .
- a preferred pre-alloy contains titanium and boron in a ratio of 5:2 to 10:1.
- the process is suitable for the manufacture of pre-alloys with 0.15 to 20 w. % titanium and 0.01 to 4 w. % boron, it has proved favourable if the pre-alloy contains 0.3 to 5, preferably 0.5 to 2, w. % Ti and 0.02 to 1, preferably 0.05 to 0.5, w. % B.
- the process in accordance with this invention is especially suitable for the manufacture of grain refinement media for the grain refinement of aluminium and aluminium alloys.
- FIG. 1 a section from the Al—Ti equilibrium diagram
- FIG. 2 a cross-section through an installation for the manufacture of a Al—Ti—B pre-alloy.
- the Al—Ti equilibrium diagram shown in FIG. 1 represents the schematic process sequence for the manufacture of an Al—Ti—B pre-alloy for the grain refinement of aluminium alloys.
- the graphic depiction A of the alloy phase to the left of the 0.5% Ti line shows the events involved in the preparation of an already solidified pre-alloy, and depiction B to the right of the 0.5% Ti line shows the events during the solidification of the pre-alloy.
- the pre-alloy melt contains TiB 2 particles in partly agglomerated form.
- the partly agglomerated TiB 2 particles are deagglomerated and homogeneously distributed by a violent melt movement by means of an ultrasonic treatment at a frequency of for example 25 kHz.
- a first cooling rate v 1 of e.g. 0.5° C./sec, a thin layer of Al 3 Ti phase is deposited on the parallel surfaces of the TiB 2 particles and simultaneously the formation of coarse grained Al 3 Ti particles is prevented.
- a plant 10 shown in FIG. 2 for the manufacture of an Al—Ti—B pre-alloy for the grain refinement of aluminium alloys comprises a reaction vessel 12 with an inlet channel 14 in its upper area and an outlet channel 16 in its lower area.
- the reaction vessel 12 is surrounded by an induction motor 18 as an electromagnetic stirring device with which the aluminium melt 20 in the reaction vessel 12 is agitated violently under formation of a vortex 22 .
- Salts containing Ti and B such as for example K 2 TiF 6 and KBF 4 are supplied in the direction of arrow 24 to the vortex 22 which mixes the salts into the aluminium melt 20 .
- the aluminium melt 20 with the reaction products is then passed through the outlet channel 16 by way of a further inlet channel 26 into the upper area of a further treatment vessel 28 .
- a further electromagnetic stirring device 30 in the lower area of the further treatment vessel 28 leads to a lower turbulent zone 32 and an upper settling zone 34 .
- the slag 36 formed through the reaction products is removed by way of the removal opening 38 from the further treatment vessel 28 .
- the cleaned aluminium melt 20 with the titanium and boron elements contained therein is added as a pre-alloy in the lower area of the further treatment vessel 28 by way of a pouring channel 38 to a mould, not shown in the drawing, of a horizontal casting machine.
- a pouring channel 38 In the area of the pouring channel 38 are arranged two ultrasound emitters 40 , 42 , the sonotrodes 44 , 46 of which dip into the melt.
- An induction heater 48 arranged below the pouring channel 38 serves to heat the melt should its temperature fall below the liquidus temperature T L Al3Ti of the Al 3 Ti phase as the melt runs from the further treatment vessel 28 into the launder 38 .
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Continuous Casting (AREA)
- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP99811137A EP1114875A1 (de) | 1999-12-10 | 1999-12-10 | Verfahren zur Herstellung einer Aluminium-Titan-Bor-Vorlegierung als Kornfeinungsmittel |
| EP99811137.1 | 1999-12-10 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US20030075020A1 true US20030075020A1 (en) | 2003-04-24 |
Family
ID=8243179
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US10/148,659 Abandoned US20030075020A1 (en) | 1999-12-10 | 2000-11-30 | Method for producing an aluminum-titanium-boron prealloy for use as a grain refiner |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US20030075020A1 (de) |
| EP (2) | EP1114875A1 (de) |
| CA (1) | CA2394485A1 (de) |
| DE (1) | DE50005366D1 (de) |
| WO (1) | WO2001042521A1 (de) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007052174A1 (en) * | 2005-11-02 | 2007-05-10 | Tubitak | Process for producing a grain refining master alloy |
| RU2625375C2 (ru) * | 2015-12-03 | 2017-07-13 | Федеральное государственное бюджетное учреждение науки Институт металлургии Уральского отделения Российской академии наук (ИМЕТ УрО РАН) | Способ получения композиционных сплавов и установка для его осуществления |
| JP2021532255A (ja) * | 2018-06-25 | 2021-11-25 | シーテック コンステリウム テクノロジー センターC−Tec Constellium Technology Center | アルミニウム合金からなる部品の製造方法 |
| CN114959348A (zh) * | 2022-06-09 | 2022-08-30 | 上海大学 | 一种高分散度Al-xMB2细化剂的制备方法和应用方法 |
| CN115558821A (zh) * | 2022-12-06 | 2023-01-03 | 北京航空航天大学 | 一种实现TiB2尺寸可控的Al-Ti-B细化剂制备方法 |
| CN115976373A (zh) * | 2022-12-30 | 2023-04-18 | 中山瑞泰铝业有限公司 | 一种铝合金材料的加工工艺及其应用 |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101768708B (zh) * | 2010-02-05 | 2012-05-23 | 深圳市新星轻合金材料股份有限公司 | 通过控制压缩比来控制铝钛硼合金晶粒细化能力的变化量的方法 |
| CN105671350A (zh) * | 2015-03-19 | 2016-06-15 | 中信戴卡股份有限公司 | 一种铝合金细化剂、其制备方法及用途 |
| EP3162460A1 (de) | 2015-11-02 | 2017-05-03 | Mubea Performance Wheels GmbH | Leichtmetallgussbauteil und verfahren zum herstellen eines leichtmetallgussbauteils |
| CN107377914A (zh) * | 2017-08-04 | 2017-11-24 | 江西金世纪特种焊接材料有限公司 | 一种铝合金焊接材料熔炼连铸设备 |
| CN109371277A (zh) * | 2018-12-11 | 2019-02-22 | 徐州宁铝业科技有限公司 | 一种用于铝合金熔炼的精炼剂及制备方法 |
| CN110157935B (zh) * | 2019-06-28 | 2021-05-07 | 上海大学 | 铸造铝硅合金用Al-V-B细化剂、其制备方法及应用 |
| CN110195168B (zh) * | 2019-07-12 | 2021-01-01 | 东北大学 | 一种铝-钛-硼细化剂板的制备工艺 |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3785807A (en) * | 1970-04-28 | 1974-01-15 | Graenges Aluminium Ab | Method for producing a master alloy for use in aluminum casting processes |
| US4612073A (en) * | 1984-08-02 | 1986-09-16 | Cabot Corporation | Aluminum grain refiner containing duplex crystals |
| US5230754A (en) * | 1991-03-04 | 1993-07-27 | Kb Alloys, Inc. | Aluminum master alloys containing strontium, boron, and silicon for grain refining and modifying aluminum alloys |
-
1999
- 1999-12-10 EP EP99811137A patent/EP1114875A1/de not_active Withdrawn
-
2000
- 2000-11-30 WO PCT/EP2000/012015 patent/WO2001042521A1/de not_active Ceased
- 2000-11-30 EP EP00983193A patent/EP1242641B1/de not_active Expired - Lifetime
- 2000-11-30 US US10/148,659 patent/US20030075020A1/en not_active Abandoned
- 2000-11-30 DE DE50005366T patent/DE50005366D1/de not_active Expired - Fee Related
- 2000-11-30 CA CA002394485A patent/CA2394485A1/en not_active Abandoned
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3785807A (en) * | 1970-04-28 | 1974-01-15 | Graenges Aluminium Ab | Method for producing a master alloy for use in aluminum casting processes |
| US4612073A (en) * | 1984-08-02 | 1986-09-16 | Cabot Corporation | Aluminum grain refiner containing duplex crystals |
| US5230754A (en) * | 1991-03-04 | 1993-07-27 | Kb Alloys, Inc. | Aluminum master alloys containing strontium, boron, and silicon for grain refining and modifying aluminum alloys |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007052174A1 (en) * | 2005-11-02 | 2007-05-10 | Tubitak | Process for producing a grain refining master alloy |
| US20080245447A1 (en) * | 2005-11-02 | 2008-10-09 | Yucel Birol | Process for Producing a Grain Refining Master Alloy |
| US7988764B2 (en) * | 2005-11-02 | 2011-08-02 | Tubitak | Process for producing a grain refining master alloy |
| RU2625375C2 (ru) * | 2015-12-03 | 2017-07-13 | Федеральное государственное бюджетное учреждение науки Институт металлургии Уральского отделения Российской академии наук (ИМЕТ УрО РАН) | Способ получения композиционных сплавов и установка для его осуществления |
| JP2021532255A (ja) * | 2018-06-25 | 2021-11-25 | シーテック コンステリウム テクノロジー センターC−Tec Constellium Technology Center | アルミニウム合金からなる部品の製造方法 |
| JP7386819B2 (ja) | 2018-06-25 | 2023-11-27 | シーテック コンステリウム テクノロジー センター | アルミニウム合金からなる部品の製造方法 |
| CN114959348A (zh) * | 2022-06-09 | 2022-08-30 | 上海大学 | 一种高分散度Al-xMB2细化剂的制备方法和应用方法 |
| CN115558821A (zh) * | 2022-12-06 | 2023-01-03 | 北京航空航天大学 | 一种实现TiB2尺寸可控的Al-Ti-B细化剂制备方法 |
| CN115976373A (zh) * | 2022-12-30 | 2023-04-18 | 中山瑞泰铝业有限公司 | 一种铝合金材料的加工工艺及其应用 |
Also Published As
| Publication number | Publication date |
|---|---|
| EP1114875A1 (de) | 2001-07-11 |
| DE50005366D1 (de) | 2004-03-25 |
| WO2001042521A8 (de) | 2001-07-12 |
| EP1242641A1 (de) | 2002-09-25 |
| CA2394485A1 (en) | 2001-06-14 |
| EP1242641B1 (de) | 2004-02-18 |
| WO2001042521A1 (de) | 2001-06-14 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AS | Assignment |
Owner name: ALCAN TECHNOLOGY & MANAGEMENT LTD., SWITZERLAND Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:HOTZ, WALTER;HOMBERGER, HEINRICH;REEL/FRAME:013245/0167 Effective date: 20020503 |
|
| STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |