EP4019166A1 - Zerstäubung von metallischen schmelzen mit kohlensäurehaltigem wasser - Google Patents

Zerstäubung von metallischen schmelzen mit kohlensäurehaltigem wasser Download PDF

Info

Publication number
EP4019166A1
EP4019166A1 EP20020640.7A EP20020640A EP4019166A1 EP 4019166 A1 EP4019166 A1 EP 4019166A1 EP 20020640 A EP20020640 A EP 20020640A EP 4019166 A1 EP4019166 A1 EP 4019166A1
Authority
EP
European Patent Office
Prior art keywords
metal
water
fluid
molten metal
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.)
Withdrawn
Application number
EP20020640.7A
Other languages
English (en)
French (fr)
Inventor
Sophie Dubiez
Bartek KAPLAN
Magnus Dahlstrom
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.)
Linde GmbH
Original Assignee
Linde GmbH
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 Linde GmbH filed Critical Linde GmbH
Priority to EP20020640.7A priority Critical patent/EP4019166A1/de
Publication of EP4019166A1 publication Critical patent/EP4019166A1/de
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/02—Making metallic powder or suspensions thereof using physical processes
    • B22F9/06—Making metallic powder or suspensions thereof using physical processes starting from liquid material
    • B22F9/08—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying
    • B22F9/082—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/06—Metallic powder characterised by the shape of the particles
    • B22F1/065—Spherical particles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/02—Making metallic powder or suspensions thereof using physical processes
    • B22F9/06—Making metallic powder or suspensions thereof using physical processes starting from liquid material
    • B22F9/08—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying
    • B22F9/082—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid
    • B22F2009/0824—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid with a specific atomising fluid
    • B22F2009/0828—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid with a specific atomising fluid with water
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/02—Making metallic powder or suspensions thereof using physical processes
    • B22F9/06—Making metallic powder or suspensions thereof using physical processes starting from liquid material
    • B22F9/08—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying
    • B22F9/082—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid
    • B22F2009/088—Fluid nozzles, e.g. angle, distance
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2999/00—Aspects linked to processes or compositions used in powder metallurgy

Definitions

  • the present invention relates generally to a method for use in producing metal powder.
  • the present invention relates to a method of producing a metal powder for use in additive manufacturing process.
  • additive manufacturing is a manufacturing technology that includes a methodology whereby a heat source melts a feedstock of material which is deposited onto a substrate.
  • Computer control of the movement of the heat source, and the source of the feedstock, makes it possible to build complex components.
  • AM additive manufacturing
  • L-PBF laser powder bed fusion
  • a metal powder is normally used, and for the repeatability of the process it is important to have the powder material with reproducible morphological characteristics, such as shape and size.
  • the particles in the powder are as close as possible to spherical, and that they have a narrow size distribution. This facilitates good packaging of the powder and allows the powder to flow well.
  • Water atomisation whereby the molten metal is treated with a stream of water at high pressure reaching 1000 bar, is a widely used technique to produce powder for additive manufacturing.
  • Another technique to produce powder is gas atomisation, whereby an argon gas or a mixture of argon and nitrogen are used to atomise molten metal.
  • the resultant metal particles are then sieved into fractions having predetermined size distributions.
  • a method of producing a metal powder for additive manufacturing process comprising:
  • the high concentration of CO 2 around the metal during the atomisation process is believed to promote the formation of spherical particles.
  • the presence of CO 2 in the atomising medium helps to reduce or even prevent evolution of CO 2 by reactions between the water and the carbon in the stream of molten metal.
  • the carbon dioxide is dissolved in water.
  • the gas when the gas is dissolved in water, for instance by way of pre-mixing with water prior to contact with the molten metal, it allows for better interaction of metal particles with the carbon dioxide in the atomising medium, thus leading to a more efficient metal particle formation.
  • the fluid further comprises carbon monoxide.
  • the presence of carbon monoxide may serve the purpose of further preventing the depletion of carbon from the molten metal and /or reacting with iron to reduce oxides present in the metal.
  • the ratio of carbon dioxide and water is at least 1 wt.%.
  • the amount of carbon dioxide is sufficient to interact with the molten metal and to suppress carbon depletion from its surface.
  • the jet of fluid is supplied through a nozzle.
  • the nozzle is a convergent-divergent nozzle.
  • supplying both molten metal and the pressurised carbon dioxide through the nozzle having both a divergent and convergent sections allows for better mixing at the point of exit of the two components due to a change in the speed of the components at the narrowing point, and thus preventing blockage of the nozzle opening.
  • the fluid is supplied at between 100 and 1000 bar pressure. In yet another embodiment, the fluid is supplied at between 600 to 850 L/min.
  • the fluid is supplied at between 600 to 850 L/min.
  • the metal comprises iron or iron alloy, preferably a steel such as alloyed steel.
  • iron or alloyed steel allows for producing a wide variety of components for automotive, industrial, food processing and medical applications.
  • the metal powder comprises substantially spherical solid particles having an aspect ratio between 1 and 1.2.
  • the presence of the spherical or near-spherical particles allows for an enhanced powder flowability and better bulk density which, in turn, will lead to a better quality of the finished product. Smooth round particles possess better packing properties and therefore spread more evenly on the powder bed and form a uniform layer.
  • Figure 1 shows a water atomisation system 100 for producing metal particles for additive manufacturing.
  • the metal is supplied into a ladle or a melter 101 where it is heated up to the desired temperature, and then transferred into a tundish 102 to avoid splashing and give a smoother flow.
  • a stream of the molten metal is then supplied into an atomising chamber 103 where it is mixed with water with carbon dioxide ("carbonated water”) dissolved in it, said mixture is supplied through the nozzles 104a, 104b.
  • carbonated water carbon dioxide
  • the molten metal the undergoes atomisation process under contact with carbonated water to form micron sized particles. It is understood that the carbonated water is supplied into the chamber 103 under pressure of between 200 and to 1000 bar and a flow rate between 600 to 850 L/min.
  • the water and metal particles form a slurry at the bottom of the chamber 103, said slurry comprising about 90% water and 10% metal particles.
  • the slurry then is transferred either in a leaching tank 105 or into a dewatering system 106.
  • the recovered water from either process is then transferred into a system 107 for cooling down, filtering and further recycling.
  • a pressure or a high pressure pump 108 pumps the recycled water back into the atomising system. It is understood that an apparatus for conventional water atomisation can be also used for carbonated water atomisation, with minimal changes to the set-up required.
  • the nozzles 104a, b may be modified to supply a mixture of water and CO 2 , and/or an additional unit may be provided for enriching water with carbon dioxide prior to contact with the molten metal.
  • the CO 2 and water may be premixed and supplied as a ready to use solution, in which case a water atomisation system as shown in figure 1 may be used without structural modification.
  • Figure 2 shows an atomiser 200 to be used for producing metal powder according to an embodiment of the present invention. It comprises the chamber 201 where the atomising of the molten metal by the carbonated water occurs, and a furnace 202 connected to the chamber. A metal 203 is supplied to the furnace 202 and is subsequently heated to reach the melting temperature. It is understood that the metal 201 can be iron or an iron alloy. The iron alloy may include, besides other elements typically used in alloys, carbon from 0.03% to greater than 1% to increase hardness and strength of iron. The temperature in the furnace 202 depends on the type of metal or metal alloy and must be sufficient to maintain the metal in a molten state.
  • the molten metal 203 is then supplied into the chamber 201 through an opening 204.
  • the molten metal 203 flows downwards under gravity and then it is subsequently treated with a one or more jets 205 of fluid.
  • the fluid may be supplied into the chamber under pressure, then a pressure system 207 may be used.
  • the fluid is supplied into the chamber 201 through a nozzle 206.
  • different kind of nozzles can be used, such as Venturi nozzle or de Laval nozzle, with the latter being the preferred choice of nozzle.
  • By using the de Laval, or divergent-convergent, nozzle it is possible to achieve higher acceleration rates of the passing fluid, thus resulting in a better mixing of the fluid with the molten metal.
  • the fluid 205 can be water with pre-dissolved carbon dioxide.
  • the fluid can further comprise carbon monoxide, to achieve a more efficient suppression of the gas evolution from the molten metal 203.
  • the jet of fluid leaves the nozzle 206, it meets the stream of molten metal 204. Due to the rapid expansion of water and dissolved CO 2 , the solid spherical or near-spherical uniform particles of metal powder 208 are formed and further deposited at the bottom of chamber 201.
  • spherical or near-spherical particles it is understood that a majority of the particles have an aspect ratio of between 1 and 2, preferably between 1 and 1.5, more preferably between 1 and 1.2. It is hypothesised that the presence of a high concentration of CO 2 in the water around the particles as they are atomised assists with the formation of spherical particles.
  • the formation of spherical or near-spherical particles leads to a better spreadability of the resultant powder when it is subsequently used for an additive manufacturing process.
  • FIG. 3 shows a method 300 which is implemented by a controller.
  • the controller is arranged to supply a molten metal 203 through an opening 204 of the furnace into the chamber 201.
  • the supply of carbonated water occurs through the at least one nozzle 206. It is understood that the controller also controls the carbonated water supply parameters, such as pressure an/or temeprature.
  • the atomised powder 208 is produced by mixing the stream of molten metal 204 with the jet 205 of atomised water used as atomising medium. If it is determined that substantially all the metal has been transformed into powder, the method proceeds to step 305 at which the removal of water occurs. It will be understood that the removal of carbonated water can be performed using conventional equipment for dewatering of metal powders that have been water atomised.
  • step 302 the process returns to step 302 of supplying more carbonated water into the nozzle.
  • the carbonated water is supplied through the nozzles 104a, 104b as the jets which hit the stream of molten metal 203 at high velocity.
  • the molten metal 203 is then atomised and deposited at the bottom of the chamber 103.
  • embodiments of the present invention can be realised in the form of hardware, software or a combination of hardware and software. Any such software may be stored in the form of volatile or non-volatile storage such as, for example, a storage device like a ROM, whether erasable or rewritable or not, or in the form of memory such as, for example, RAM, memory chips, device or integrated circuits or on an optically or magnetically readable medium such as, for example, a CD, DVD, magnetic disk or magnetic tape. It will be appreciated that the storage devices and storage media are embodiments of machine-readable storage that are suitable for storing a program or programs that, when executed, implement embodiments of the present invention.
  • embodiments provide a program comprising code for implementing a system or method as claimed in any preceding claim and a machine readable storage storing such a program. Still further, embodiments of the present invention may be conveyed electronically via any medium such as a communication signal carried over a wired or wireless connection and embodiments suitably encompass the same.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Nanotechnology (AREA)
  • Manufacture Of Metal Powder And Suspensions Thereof (AREA)
EP20020640.7A 2020-12-22 2020-12-22 Zerstäubung von metallischen schmelzen mit kohlensäurehaltigem wasser Withdrawn EP4019166A1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP20020640.7A EP4019166A1 (de) 2020-12-22 2020-12-22 Zerstäubung von metallischen schmelzen mit kohlensäurehaltigem wasser

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP20020640.7A EP4019166A1 (de) 2020-12-22 2020-12-22 Zerstäubung von metallischen schmelzen mit kohlensäurehaltigem wasser

Publications (1)

Publication Number Publication Date
EP4019166A1 true EP4019166A1 (de) 2022-06-29

Family

ID=74003662

Family Applications (1)

Application Number Title Priority Date Filing Date
EP20020640.7A Withdrawn EP4019166A1 (de) 2020-12-22 2020-12-22 Zerstäubung von metallischen schmelzen mit kohlensäurehaltigem wasser

Country Status (1)

Country Link
EP (1) EP4019166A1 (de)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1413651A (en) * 1971-11-04 1975-11-12 Singer A R E Atomising of metals
DE4005696A1 (de) * 1990-02-20 1991-08-29 Mannesmann Ag Verfahren zur herstellung eines feinteiligen metallischen pulvers
WO2019157594A1 (en) * 2018-02-15 2019-08-22 5N Plus Inc. High melting point metal or alloy powders atomization manufacturing processes

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1413651A (en) * 1971-11-04 1975-11-12 Singer A R E Atomising of metals
DE4005696A1 (de) * 1990-02-20 1991-08-29 Mannesmann Ag Verfahren zur herstellung eines feinteiligen metallischen pulvers
WO2019157594A1 (en) * 2018-02-15 2019-08-22 5N Plus Inc. High melting point metal or alloy powders atomization manufacturing processes

Similar Documents

Publication Publication Date Title
CN108941588B (zh) 一种激光成形用镍基高温合金粉末的制备方法
US10273567B2 (en) Centrifugal atomization of iron-based alloys
EP0198613B1 (de) Verfahren zur Herstellung von metallischen Produkten
US5310165A (en) Atomization of electroslag refined metal
US5863618A (en) Method for producing a chromium carbide-nickel chromium atomized powder
JPH0819446B2 (ja) 不安定な溶融液流を噴霧する装置および方法
JP2016211027A (ja) 金属粉末の製造方法及び製造装置
JPS61226163A (ja) 金属製品製造方法
KR20040067608A (ko) 금속 분말 및 그 제조 방법
EP4019167A1 (de) Zerstäubung von metallischen schmelzen unter verwendung von flüssigem co2
EP4019166A1 (de) Zerstäubung von metallischen schmelzen mit kohlensäurehaltigem wasser
JPH03502545A (ja) 溶融体を噴霧する方法及び該方法を使用する装置
CA2570924A1 (en) Method for producing metal products
EP4197674A1 (de) Kontrollierte atmosphäre und optimierte zerstäubung für die pulverherstellung
US4780130A (en) Process to increase yield of fines in gas atomized metal powder using melt overpressure
JPS63230806A (ja) 金属粉末製造ガス噴霧装置
JP2004107740A (ja) 水アトマイズ法による金属粉末の製造方法及び製造装置、金属粉末、並びに部品
EP3290136A1 (de) Verfahren zur herstellung von metallischen pulvern
Brewin et al. Production of high alloy powders by water atomization
JPH04266475A (ja) 複合材料の製造方法
JP2002309361A (ja) 溶射用粉末の製造方法および溶射粉末
JPH0441063A (ja) スプレーフォーミング法
JP7498043B2 (ja) 金属粉末の製造方法
JPH06623A (ja) 噴霧成形法
KR100413282B1 (ko) 용탕반응 분무주조장치

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

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

Free format text: STATUS: THE APPLICATION HAS BEEN PUBLISHED

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

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

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20230103