EP0518815A1 - Process for heating a metal alloy workpiece - Google Patents

Process for heating a metal alloy workpiece Download PDF

Info

Publication number
EP0518815A1
EP0518815A1 EP92810382A EP92810382A EP0518815A1 EP 0518815 A1 EP0518815 A1 EP 0518815A1 EP 92810382 A EP92810382 A EP 92810382A EP 92810382 A EP92810382 A EP 92810382A EP 0518815 A1 EP0518815 A1 EP 0518815A1
Authority
EP
European Patent Office
Prior art keywords
temperature
workpiece
heating
alloy
workpieces
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.)
Granted
Application number
EP92810382A
Other languages
German (de)
French (fr)
Other versions
EP0518815B1 (en
Inventor
Jean-Pierre Gabathuler
Yves Krähenbühl
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
3A Composites International AG
Original Assignee
Alusuisse Lonza Services Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Alusuisse Lonza Services Ltd filed Critical Alusuisse Lonza Services Ltd
Publication of EP0518815A1 publication Critical patent/EP0518815A1/en
Application granted granted Critical
Publication of EP0518815B1 publication Critical patent/EP0518815B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/34—Methods of heating
    • 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 method for heating a workpiece made of a solid metal alloy to a final temperature between the solidus and liquidus temperature of the alloy, in particular for producing a partially solid, partially liquid, thixotropic state of the workpiece.
  • these partially solid, partially liquid metal alloy phases are first cooled to below the solidus temperature of the alloy - generally to room temperature - and only heated to the required processing temperature at which the thixotropic properties appear just before they are further processed.
  • Coarsening of the cast grains is undesirable both in the production of the metal alloy phase with thixotropic properties and in the subsequent heating of the workpieces to the further processing temperature.
  • the inventors have set themselves the goal of creating a method of the type mentioned at the outset with which the thixotropic state of a workpiece made of a metal alloy for whose further processing can be stopped inexpensively and without having to accept a significant coarsening of the grain.
  • the workpiece is heated convectively in a first step, by heat conduction, heat radiation or another non-inductive heat transfer to a temperature just below the solidus temperature of the metal alloy and in a subsequent second step inductively to the final temperature.
  • the desired final temperature is reached quickly by the inductive heating in the second step and consequently the dwell time of the workpiece in the partially solid, liquid state, in which the greatest tendency to coarsen the grain is observed, is kept as short as possible. Since in this second step there is only a temperature increase on the workpiece of approximately 30 ° to 100 ° C., the power and thus the size of the induction heating system can also be designed to be relatively small and therefore inexpensive. On the other hand, the energy loss during heating through non-inductive heat transfer in the first step, taking into account the large temperature interval, is significantly less than with a corresponding induction heating.
  • the temperature reached after the first heating step is about 10 ° to 50 ° C below the solidus temperature of the metal alloy.
  • the solidus temperature should never be exceeded.
  • the inductive heating of the workpiece in the second step is preferably carried out with an alternating current frequency between 50 and 1000 Hz and a heating power between approximately 10 and 200 kW.
  • the alternating current frequency and heating power are matched to one another in such a way that the surface temperature of the workpiece never exceeds the desired end temperature while maintaining the shortest possible time until the end temperature is reached.
  • the process according to the invention is expediently carried out continuously under production conditions.
  • the heating in the first step is preferably carried out in a continuous or tunnel oven and in the second step cyclically by transferring it into successive induction coils, the throughput speed of the workpieces through the continuous or tunnel oven, the cycle time of the induction heating system and the cycle time of the subsequent further processing system being coordinated will.
  • Several lines of induction coils can also be used per continuous or tunnel furnace.
  • the method according to the invention is preferably used in the production of workpieces intended for further processing with thixotropic properties, in particular for further processing bolts or ingots in die casting, forging, rolling and pressing systems.
  • the method is particularly suitable for heating workpieces made of aluminum alloys.
  • An alloy of the type AlSi7Mg with 6.9% by weight Si and 0.4% by weight Mg was cast in a continuous casting installation to produce a thixotropic structure to form a strand of 75 mm in diameter and cut into bolts of 180 mm in height.
  • the average diameter of the globular cast grains was less than 100 ⁇ m.
  • the solidus temperature of the alloy is 555 ° C.
  • the bolts were heated to the set furnace temperature of 540 ° C for two hours in a holding oven with air circulation.
  • the bolts were then heated in an induction coil with an output of 25 kW and an AC frequency of 250 Hz within 6 minutes to the final temperature of about 580 ° C - corresponding to a liquid metal content of 30 to 40%.
  • Metallographic examination of bolt cross sections showed that no significant grain coarsening had occurred, i.e. the average grain size was still below 100 ⁇ m.

Abstract

Ein Werkstück aus einer Metallegierung wird in einem ersten Schritt konvektiv, durch Wärmeleitung, Wärmestrahlung oder eine andere nicht-induktive Wärmeübertragung auf eine knapp unterhalb der Solidustemperatur der Legierung liegende Temperatur und in einem anschliessenden zweiten Schritt induktiv auf die zwischen Solidus- und Liquidustemperatur liegende Endtemperatur aufgezeizt. Das Verfahren ist insbesondere geeignet zur Herstellung von zur Weiterverarbeitung vorgesehenen Werkstücken mit thixotropen Eigenschaften, insbesondere zur Weiterverarbeitung von Bolzen oder Barren in Druckgiess-, Schmiede-, Walz- und Pressanlagen.In a first step, a workpiece made of a metal alloy is convectively, by means of heat conduction, heat radiation or another non-inductive heat transfer to a temperature just below the solidus temperature of the alloy, and in a subsequent second step inductively to the final temperature between solidus and liquidus temperature . The method is particularly suitable for producing workpieces intended for further processing with thixotropic properties, in particular for further processing bolts or ingots in die casting, forging, rolling and pressing systems.

Description

Die Erfindung betrifft ein Verfahren zum Aufheizen eines Werkstückes aus einer festen Metallegierung auf eine zwischen Solidus- und Liquidustemperatur der Legierung liegende Endtemperatur, insbesondere zur Herstellung eines teilfesten-teilflüssigen, thixotropen Zustandes des Werkstückes.The invention relates to a method for heating a workpiece made of a solid metal alloy to a final temperature between the solidus and liquidus temperature of the alloy, in particular for producing a partially solid, partially liquid, thixotropic state of the workpiece.

Bei der Herstellung von Metallegierungsphasen mit thixotropen Eigenschaften ist bekannt, die Temperatur einer Legierungsschmelze auf einen Wert zwischen Solidus- und Liquidustemperatur einzustellen und den hierbei entstehenden Legierungsbrei zur Umwandlung der beim Erstarrungsvorgang sich bildenden Dendriten zu im wesentlichen globulitischen Gusskörnern kräftig zu rühren. Dieses Verfahren sowie die Einsatzmöglichkeiten der damit erzeugten Metallegierungsphase mit thixotropen Eigenschaften sind beispielsweise in US-A-3 948 650 und US-A-3 959 651 ausführlich beschrieben.In the production of metal alloy phases with thixotropic properties, it is known to set the temperature of an alloy melt to a value between solidus and liquidus temperature and to stir the resulting alloy slurry vigorously to convert the dendrites formed during the solidification process to essentially globulitic cast grains. This method and the possible uses of the metal alloy phase produced therewith with thixotropic properties are described in detail, for example, in US Pat. Nos. 3,948,650 and 3,959,651.

Im allgemeinen werden diese teilfesten-teilflüssigen Metallegierungsphasen zunächst unter die Solidustemperatur der Legierung -- im allgemeinen auf Raumtemperatur -- abgekühlt und erst kurz vor deren Weiterverarbeitung auf die erforderliche Verarbeitungstemperatur, bei welcher die thixotropen Eigenschaften in Erscheinung treten, aufgeheizt.In general, these partially solid, partially liquid metal alloy phases are first cooled to below the solidus temperature of the alloy - generally to room temperature - and only heated to the required processing temperature at which the thixotropic properties appear just before they are further processed.

Sowohl bei der Herstellung der Metallegierungsphase mit thixotropen Eigenschaften als auch beim späteren nochmaligen Aufheizen der Werkstücke auf die Weiterverarbeitungstemperatur ist eine Vergröberung der Gusskörner unerwünscht.Coarsening of the cast grains is undesirable both in the production of the metal alloy phase with thixotropic properties and in the subsequent heating of the workpieces to the further processing temperature.

Zum Aufheizen von metallischen Werkstoffen ist allgemein bekannt, oel-, gas- oder widerstandsbeheizte Öfen mit oder ohne Luftumwälzung oder auch Induktionsöfen einzusetzen.For heating metallic materials, it is generally known to use oil, gas or resistance-heated furnaces with or without air circulation or also induction furnaces.

Angesichts dieser Gegebenheiten haben sich die Erfinder zum Ziel gesetzt, ein Verfahren der eingangs erwähnten Art zu schaffen, mit welchem der thixotrope Zustand eines Werkstückes aus einer Metallegierung für dessen Weiterverarbeitung kostengünstig und ohne Inkaufnahme einer wesentlichen Kornvergröberung eingestellt werden kann.In view of these circumstances, the inventors have set themselves the goal of creating a method of the type mentioned at the outset with which the thixotropic state of a workpiece made of a metal alloy for whose further processing can be stopped inexpensively and without having to accept a significant coarsening of the grain.

Zur erfindungsgemässen Lösung der Aufgabe führt, dass das Werkstück in einem ersten Schritt konvektiv, durch Wärmeleitung, Wärmestrahlung oder eine andere nicht-induktive Wärmeübertragung auf eine knapp unterhalb der Solidustemperatur der Metallegierung liegende Temperatur und in einem anschliessenden zweiten Schritt induktiv auf die Endtemperatur aufgeheizt wird.To achieve the object according to the invention, the workpiece is heated convectively in a first step, by heat conduction, heat radiation or another non-inductive heat transfer to a temperature just below the solidus temperature of the metal alloy and in a subsequent second step inductively to the final temperature.

Mit dem erfindungsgemässen Verfahren wird einerseits die gewünschte Endtemperatur durch die induktive Aufheizung im zweiten Schritt schnell erreicht und demzufolge die Verweilzeit des Werkstückes im teilfestenteilflüssigen Zustand, in welchem die stärkste Neigung zur Kornvergröberung beobachtet wird, möglichst kurz gehalten. Da in diesem zweiten Schritt nur eine Temperaturerhöhung am Werkstück von etwa 30° bis 100° C erfolgt, kann zudem die Leistung und damit die Grösse der Induktionsheizanlage verhältnismässig klein und damit kostengünstig ausgelegt werden. Andererseits ist der Energieverlust bei der Aufheizung durch nicht-induktive Wärmeübertragung im ersten Schritt unter Berücksichtigung des grossen Temperaturintervalls wesentlich geringer als bei einer entsprechenden Induktionsheizung.With the method according to the invention, on the one hand, the desired final temperature is reached quickly by the inductive heating in the second step and consequently the dwell time of the workpiece in the partially solid, liquid state, in which the greatest tendency to coarsen the grain is observed, is kept as short as possible. Since in this second step there is only a temperature increase on the workpiece of approximately 30 ° to 100 ° C., the power and thus the size of the induction heating system can also be designed to be relatively small and therefore inexpensive. On the other hand, the energy loss during heating through non-inductive heat transfer in the first step, taking into account the large temperature interval, is significantly less than with a corresponding induction heating.

Unter Praxisbedingungen liegt die nach dem ersten Aufheizschritt erreichte Temperatur etwa 10° bis 50° C unterhalb der Solidustemperatur der Metallegierung. Die Solidustemperatur sollte auf keinen Fall überschritten werden.Under practical conditions, the temperature reached after the first heating step is about 10 ° to 50 ° C below the solidus temperature of the metal alloy. The solidus temperature should never be exceeded.

Die induktive Aufheizung des Werkstückes im zweiten Schritt erfolgt bevorzugt mit einer Wechselstromfrequenz zwischen 50 und 1000 Hz und einer Heizleistung zwischen etwa 10 und 200 kW. Wechselstromfrequenz und Heizleistung werden derart aufeinander abgestimmt, dass unter Einhaltung einer möglichst kurzen Zeit bis zum Erreichen der Endtemperatur die Oberflächentemperatur des Werkstückes die gewünschte Endtemperatur nie übersteigt.The inductive heating of the workpiece in the second step is preferably carried out with an alternating current frequency between 50 and 1000 Hz and a heating power between approximately 10 and 200 kW. The alternating current frequency and heating power are matched to one another in such a way that the surface temperature of the workpiece never exceeds the desired end temperature while maintaining the shortest possible time until the end temperature is reached.

Unter Produktionsbedingungen wird das erfindungsgemässe Verfahren zweckmässigerweise kontinuierlich durchgeführt. Hierbei erfolgt das Aufheizen im ersten Schritt bevorzugt in einem Durchlauf- oder Tunnelofen und im zweiten Schritt taktweise durch jeweiliges Überführen in aufeinanderfolgende Induktionsspulen, wobei die Durchlaufgeschwindigkeit der Werkstücke durch den Durchlauf- oder Tunnelofen, die Taktzeit der Induktionsheizanlage sowie die Taktzeit der nachfolgenden Weiterverarbeitungssanlage aufeinander abgestimmt werden. Pro Durchlauf- oder Tunnelofen können auch mehrere Linien von Induktionsspulen eingesetzt werden.The process according to the invention is expediently carried out continuously under production conditions. The heating in the first step is preferably carried out in a continuous or tunnel oven and in the second step cyclically by transferring it into successive induction coils, the throughput speed of the workpieces through the continuous or tunnel oven, the cycle time of the induction heating system and the cycle time of the subsequent further processing system being coordinated will. Several lines of induction coils can also be used per continuous or tunnel furnace.

Ein weiterer Vorteil der erfindungsgemässen Lösung ist darin zu sehen, dass im Falle eines Unterbruchs an der Weiterverarbeitungsanlage weniger Ausschuss an Werkstücken im teilfesten-teilfüssigen Zustand entsteht als bei einem taktweisen Verfahren mit induktiver Aufheizung auch im ersten Schritt, da mit dem erfindungsgemässen Verfahren bei gleicher Produktionsgeschwindigkeit weniger Induktionsspulen erforderlich sind.Another advantage of the solution according to the invention can be seen in the fact that, in the event of an interruption in the further processing system, fewer rejects on workpieces in the partially solid / partially liquid state occur than in a cycle-wise method with inductive heating also in the first step, since with the method according to the invention at the same production speed fewer induction coils are required.

Das erfindungsgemässe Verfahren wird bevorzugt angewendet bei der Herstellung von zur Weiterverarbeitung vorgesehenen Werkstücken mit thixotropen Eigenschaften, insbesondere zur Weiterverarbeitung von Bolzen oder Barren in Druckgiess-, Schmiede-, Walz- und Pressanlagen.The method according to the invention is preferably used in the production of workpieces intended for further processing with thixotropic properties, in particular for further processing bolts or ingots in die casting, forging, rolling and pressing systems.

Das Verfahren ist insbesondere geeignet zum Aufheizen von Werkstücken aus Aluminiumlegierungen.The method is particularly suitable for heating workpieces made of aluminum alloys.

Das erfindungsgemässe Verfahren wird nachstehend anhand eines Ausführungsbeispiels näher erläutert.The method according to the invention is explained in more detail below using an exemplary embodiment.

Beispielexample

Eine Legierung des Typs AlSi7Mg mit 6,9 Gew.-% Si und 0,4 Gew.-% Mg wurde in einer Stranggiessanlage unter Erzeugung eines thixotropen Gefüges zu einem Strang von 75 mm Durchmesser vergossen und zu Bolzen von 180 mm Höhe geschnitten. Der durchschnittliche Durchmesser der globulitischen Gusskörner betrug weniger als 100 µm. Die Solidustemperatur der Legierung liegt bei 555° C. Die Bolzen wurden während zwei Stunden in einem Warmhalteofen mit Luftumwälzung auf die eingestellte Ofentemperatur von 540° C aufgeheizt. Anschliessend wurden die Bolzen in einer Induktionsspule mit einer Leistung von 25 kW und einer Wechselstromfrequenz von 250 Hz innerhalb von 6 Min. auf die Endtemperatur von etwa 580° C -- entsprechend einem Flüssigmetallanteil von 30 bis 40 % -- aufgeheizt. Die metallographische Untersuchung an Bolzenquerschnitten zeigte, dass keine wesentliche Kornvergröberung eingetreten war, d.h. die durchschnittliche Korngrösse lag immernoch unterhalb von 100 µm.An alloy of the type AlSi7Mg with 6.9% by weight Si and 0.4% by weight Mg was cast in a continuous casting installation to produce a thixotropic structure to form a strand of 75 mm in diameter and cut into bolts of 180 mm in height. The average diameter of the globular cast grains was less than 100 µm. The solidus temperature of the alloy is 555 ° C. The bolts were heated to the set furnace temperature of 540 ° C for two hours in a holding oven with air circulation. The bolts were then heated in an induction coil with an output of 25 kW and an AC frequency of 250 Hz within 6 minutes to the final temperature of about 580 ° C - corresponding to a liquid metal content of 30 to 40%. Metallographic examination of bolt cross sections showed that no significant grain coarsening had occurred, i.e. the average grain size was still below 100 µm.

Claims (10)

Verfahren zum Aufheizen eines Werkstückes aus einer festen Metallegierung auf eine zwischen Solidus- und Liquidustemperatur der Legierung liegende Endtemperatur, insbesondere zur Herstellung eines teilfesten bzw. teilflüssigen, thixotropen Zustandes des Werkstückes,
   dadurch gekennzeichnet,
   dass das Werkstück in einem ersten Schritt konvektiv, durch Wärmeleitung, Wärmestrahlung oder eine andere nicht-induktive Wärmeübertragung auf eine knapp unterhalb der Solidustemperatur der Legierung liegende Temperatur und in einem anschliessenden zweiten Schritt induktiv auf die Endtemperatur aufgeheizt wird.Process for heating a workpiece made of a solid metal alloy to an end temperature between the solidus and liquidus temperature of the alloy, in particular for producing a partially solid or partially liquid, thixotropic state of the workpiece,
characterized,
that the workpiece is convectively heated in a first step, by thermal conduction, heat radiation or another non-inductive heat transfer to a temperature just below the solidus temperature of the alloy and in a subsequent second step inductively to the final temperature. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass das Werkstück im ersten Schritt auf eine 10° bis 50° C unterhalb der Solidustemperatur der Legierung liegende Temperatur aufgeheizt wird.A method according to claim 1, characterized in that the workpiece is heated in the first step to a temperature 10 ° to 50 ° C below the solidus temperature of the alloy. Verfahren nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass das Werkstück im zweiten Schritt mit einer Wechselstromfrequenz zwischen 50 und 1000 Hz aufgeheizt wird.A method according to claim 1 or 2, characterized in that the workpiece is heated in the second step with an alternating current frequency between 50 and 1000 Hz. Verfahren nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass das Werkstück im zweiten Schritt mit einer Leistung zwischen 10 und 200 kW aufgeheizt wird.Method according to one of claims 1 to 3, characterized in that the workpiece is heated in the second step with a power between 10 and 200 kW. Verfahren nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, dass beim Aufheizen im zweiten Schritt Wechselstromfrequenz und Heizleistung derart aufeinander abgestimmt werden, dass unter Einhaltung einer möglichst kurzen Zeit bis zum Erreichen der Endtemperatur die Oberflächentemperatur des Werkstückes die gewünschte Endtemperatur nie übersteigt.Method according to one of claims 1 to 4, characterized in that when heating in the second step, the alternating current frequency and heating power are coordinated with one another in such a way that the surface temperature of the workpiece never exceeds the desired final temperature while maintaining the shortest possible time until the final temperature is reached. Verfahren nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, dass das Aufheizen der Werkstücke im ersten Schritt kontinuierlich in einem Durchlauf- oder Tunnelofen durchgeführt wird.Method according to one of claims 1 to 5, characterized in that the heating of the workpieces in the first step continuously is carried out in a continuous or tunnel furnace. Verfahren nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, dass das Aufheizen der Werkstücke im zweiten Schritt taktweise in mehreren aufeinanderfolgenden Induktionsspulen durchgeführt wird.Method according to one of claims 1 to 6, characterized in that the heating of the workpieces in the second step is carried out intermittently in a plurality of successive induction coils. Verfahren nach den Ansprüchen 6 und 7, dadurch gekennzeichnet, dass pro Durchlauf- oder Tunnelofen mehrere Induktionsspulenlinien eingesetzt werden.Method according to claims 6 and 7, characterized in that several induction coil lines are used per continuous or tunnel furnace. Anwendung des Verfahrens nach einem der Ansprüche 1 bis 8 zur Herstellung von zur Weiterverarbeitung vorgesehenen Werkstücken mit thixotropen Eigenschaften, insbesondere zur Weiterverarbeitung von Bolzen oder Barren in Druckgiess-, Schmiede-, Walz- und Pressanlagen.Application of the method according to one of claims 1 to 8 for the production of workpieces intended for further processing with thixotropic properties, in particular for further processing bolts or ingots in die casting, forging, rolling and pressing systems. Anwendung des Verfahrens nach einem der Ansprüche 1 bis 9 auf Werkstücke aus Aluminiumlegierungen.Application of the method according to one of claims 1 to 9 to workpieces made of aluminum alloys.
EP92810382A 1991-06-10 1992-05-21 Process for heating a metal alloy workpiece Expired - Lifetime EP0518815B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CH1730/91 1991-06-10
CH1730/91A CH683267A5 (en) 1991-06-10 1991-06-10 A method for heating a workpiece of a metal alloy.

Publications (2)

Publication Number Publication Date
EP0518815A1 true EP0518815A1 (en) 1992-12-16
EP0518815B1 EP0518815B1 (en) 1994-12-28

Family

ID=4217257

Family Applications (1)

Application Number Title Priority Date Filing Date
EP92810382A Expired - Lifetime EP0518815B1 (en) 1991-06-10 1992-05-21 Process for heating a metal alloy workpiece

Country Status (4)

Country Link
US (1) US5282910A (en)
EP (1) EP0518815B1 (en)
CH (1) CH683267A5 (en)
DE (1) DE59201065D1 (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2720213A1 (en) * 1994-05-18 1995-11-24 Buehler Ag Geb Method and devices for heating metallic bodies.
EP0692328A1 (en) * 1994-06-14 1996-01-17 Salzburger Aluminium Aktiengesellschaft Process for manufacturing of cast articles, made from aluminium alloys
EP0703300A1 (en) * 1994-09-23 1996-03-27 Reynolds Wheels International Ltd. A method and equipment for bringing metal alloy ingots, billets and the like to the semisolid or semiliquid state in readiness for thixotropic forming
DE19532253A1 (en) * 1995-09-01 1997-03-06 Peak Werkstoff Gmbh Process for the production of thin tubes (II)
DE19532244A1 (en) * 1995-09-01 1997-03-06 Peak Werkstoff Gmbh Process for the production of thin tubes (I)
WO1997010065A1 (en) * 1995-09-13 1997-03-20 The Whitaker Corporation Apparatus for preparing a preform slug to be used in a manufacturing operation
FR2747327A1 (en) * 1996-04-11 1997-10-17 Pechiney Recherche Heating apparatus for extruding aluminium alloys
DE19532252C2 (en) * 1995-09-01 1999-12-02 Erbsloeh Ag Method of manufacturing bushings

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19836883A1 (en) * 1998-08-14 2000-02-17 Schuler Hydrap Gmbh & Co Kg Process for the production of molded parts from thixotropic metal alloys

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2266748A1 (en) * 1974-04-04 1975-10-31 Pechiney Aluminium
GB2112676A (en) * 1982-01-06 1983-07-27 Olin Corp Method and apparatus for forming a thixoforged copper base alloy cartridge casing
EP0090253A2 (en) * 1982-03-30 1983-10-05 Alumax Inc. Fine grained metal composition
EP0093248A2 (en) * 1982-03-30 1983-11-09 Alumax Inc. Process and apparatus for providing improved slurry cast structures by hot working
EP0158946A2 (en) * 1984-04-20 1985-10-23 Park-Ohio Industries, Inc. Method of and apparatus for heating non-magnetic metal work pieces

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3948650A (en) * 1972-05-31 1976-04-06 Massachusetts Institute Of Technology Composition and methods for preparing liquid-solid alloys for casting and casting methods employing the liquid-solid alloys
US3959651A (en) * 1974-04-24 1976-05-25 American Optical Corporation Electron microscope
IT1239118B (en) * 1989-11-24 1993-09-28 Elind SYSTEM FOR HEATING BARS AND STEEL BILLS Upstream of a SHEAR FOR SUBSEQUENT PROCESSING
US5009844A (en) * 1989-12-01 1991-04-23 General Motors Corporation Process for manufacturing spheroidal hypoeutectic aluminum alloy

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2266748A1 (en) * 1974-04-04 1975-10-31 Pechiney Aluminium
GB2112676A (en) * 1982-01-06 1983-07-27 Olin Corp Method and apparatus for forming a thixoforged copper base alloy cartridge casing
EP0090253A2 (en) * 1982-03-30 1983-10-05 Alumax Inc. Fine grained metal composition
EP0093248A2 (en) * 1982-03-30 1983-11-09 Alumax Inc. Process and apparatus for providing improved slurry cast structures by hot working
EP0158946A2 (en) * 1984-04-20 1985-10-23 Park-Ohio Industries, Inc. Method of and apparatus for heating non-magnetic metal work pieces

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2725391A1 (en) * 1994-05-18 1996-04-12 Buehler Ag Geb PRESSURE MOLDING INSTALLATION WITH TIME TRANSDUCER
FR2726495A1 (en) * 1994-05-18 1996-05-10 Buehler Ag Geb PRESSURE MOLDING INSTALLATION WITH PRESSURE SENSOR
FR2720213A1 (en) * 1994-05-18 1995-11-24 Buehler Ag Geb Method and devices for heating metallic bodies.
EP0692328A1 (en) * 1994-06-14 1996-01-17 Salzburger Aluminium Aktiengesellschaft Process for manufacturing of cast articles, made from aluminium alloys
US5665302A (en) * 1994-09-23 1997-09-09 Reynolds Wheels International Ltd. Method and equipment for bringing metal alloy ingots, billets and the like to the semisolid or semiliquid state in readiness for thixotropic forming
EP0703300A1 (en) * 1994-09-23 1996-03-27 Reynolds Wheels International Ltd. A method and equipment for bringing metal alloy ingots, billets and the like to the semisolid or semiliquid state in readiness for thixotropic forming
US5869811A (en) * 1994-09-23 1999-02-09 Reynolds Wheels International Ltd. Method and equipment for bringing metal alloy ingots, billets and the like to the semisolid or semiliquid state in readiness for thixotropic forming
DE19532244A1 (en) * 1995-09-01 1997-03-06 Peak Werkstoff Gmbh Process for the production of thin tubes (I)
DE19532253C2 (en) * 1995-09-01 1998-07-02 Peak Werkstoff Gmbh Process for the production of thin-walled pipes (II)
DE19532244C2 (en) * 1995-09-01 1998-07-02 Peak Werkstoff Gmbh Process for the production of thin-walled tubes (I)
DE19532253A1 (en) * 1995-09-01 1997-03-06 Peak Werkstoff Gmbh Process for the production of thin tubes (II)
DE19532252C2 (en) * 1995-09-01 1999-12-02 Erbsloeh Ag Method of manufacturing bushings
US6030577A (en) * 1995-09-01 2000-02-29 Erbsloh Aktiengesellschaft Process for manufacturing thin pipes
WO1997010065A1 (en) * 1995-09-13 1997-03-20 The Whitaker Corporation Apparatus for preparing a preform slug to be used in a manufacturing operation
FR2747327A1 (en) * 1996-04-11 1997-10-17 Pechiney Recherche Heating apparatus for extruding aluminium alloys

Also Published As

Publication number Publication date
CH683267A5 (en) 1994-02-15
DE59201065D1 (en) 1995-02-09
US5282910A (en) 1994-02-01
EP0518815B1 (en) 1994-12-28

Similar Documents

Publication Publication Date Title
EP0224016B1 (en) Wrought aluminium alloy of the type al-cu-mg having a high strength in the temperature range between 0 and 250o c
DE3300205A1 (en) METHOD AND DEVICE FOR THE PRODUCTION OF CARTRIDGE SLEEVES FROM A COPPER BASED ALLOY MOLDED IN THE THIXOTROPICAL CONDITION, AND PRODUCT PRODUCED THEREOF
DE102016123555A1 (en) WELDING ELECTRODE FOR USE IN RESISTANCE SPOT WELDING OF WORKPIECE STACKS CONTAINING AN ALUMINUM WORKPIECE AND A STEEL WORKPIECE
DE2133103A1 (en) Ligature recovering in the heat
DE2514386B2 (en) PROCESS FOR IMPROVING THE FORMABILITY OF LIGHT ALLOYS
DE2508838B2 (en) HARD OR SEMI-HARD MAGNETIC ALLOY
EP0518815A1 (en) Process for heating a metal alloy workpiece
DE2638680A1 (en) SUPRAL CONDUCTING COMPOSITE BODY AND METHOD FOR PRODUCING IT
DE1783163A1 (en) PROCESS FOR IMPROVING THE ELECTRICAL CONDUCTIVITY AND STRENGTH OF COPPER ALLOYS
EP0263070B1 (en) Process for the production of a fine-grained recrystallised sheet
DE2242235B2 (en) Superplastic aluminum alloy
EP0035069A1 (en) Memory alloy based on Cu-Al or on Cu-Al-Ni and process for the stabilisation of the two-way effect
EP0702375B1 (en) Overhead contact wire of high speed electrical railways and process for manufacturing the same
DE3050471C2 (en) Electro-slag welding method
EP0779372B1 (en) Overhead contact wire for high speed electrical railways and process for manufacturing the same
DE3417273C2 (en) Copper-nickel alloy for electrically conductive material for integrated circuits
DE883222C (en) Method and device for coating metal objects with metal
DE1483265B2 (en) USE OF A MAGNESIUM ALLOY
DE102017107318A1 (en) PROCESS FOR RESISTANCE SPOT WELDING OF ALUMINUM TO STEEL
DE2112370C2 (en) Process for the production of superplastically deformable copper-containing zinc or zinc-aluminum alloys
DE2029584A1 (en) Method of manufacturing an electrical conductor using aluminum
DE2519444C3 (en) Process for increasing the strength and toughness of castings
DE3245656C2 (en) Process for Improving the Creep Resistance of Lead-Containing 6000 Series Aluminum Alloys (According to Aluminum Association Standards)
DE1912932C3 (en) Process for the heat treatment of wrought aluminum alloys of the AIMgSi type to improve the processability by extrusion
DE2949673A1 (en) METHOD FOR PRODUCING A COMPOSED GRAIN STRUCTURE IN OBJECTS FROM NICKEL ALLOY

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): BE CH DE DK FR GB IT LI NL

17P Request for examination filed

Effective date: 19930521

17Q First examination report despatched

Effective date: 19930729

ITF It: translation for a ep patent filed

Owner name: DE DOMINICIS & MAYER S.R.L.

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): CH DE FR GB IT LI

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 19950109

REF Corresponds to:

Ref document number: 59201065

Country of ref document: DE

Date of ref document: 19950209

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20030422

Year of fee payment: 12

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20030522

Year of fee payment: 12

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: CH

Payment date: 20030530

Year of fee payment: 12

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20030610

Year of fee payment: 12

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20040521

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: LI

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20040531

Ref country code: CH

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20040531

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20041201

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20040521

REG Reference to a national code

Ref country code: CH

Ref legal event code: PL

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050131

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

Effective date: 20050521