US20020134198A1 - Method and device for atomizing molten metals - Google Patents
Method and device for atomizing molten metals Download PDFInfo
- Publication number
- US20020134198A1 US20020134198A1 US10/070,527 US7052702A US2002134198A1 US 20020134198 A1 US20020134198 A1 US 20020134198A1 US 7052702 A US7052702 A US 7052702A US 2002134198 A1 US2002134198 A1 US 2002134198A1
- Authority
- US
- United States
- Prior art keywords
- melt
- lance
- gas
- laval nozzle
- hot gas
- 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
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
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B3/00—General features in the manufacture of pig-iron
- C21B3/04—Recovery of by-products, e.g. slag
- C21B3/06—Treatment of liquid slag
- C21B3/08—Cooling slag
-
- 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
- C22C1/10—Alloys containing non-metals
- C22C1/1036—Alloys containing non-metals starting from a melt
- C22C1/1042—Alloys containing non-metals starting from a melt by atomising
-
- 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
-
- 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
- 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
- B22F2009/0892—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 casting nozzle; controlling metal stream in or after the casting nozzle
-
- 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
- B22F2998/00—Supplementary information concerning processes or compositions relating to powder metallurgy
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B2400/00—Treatment of slags originating from iron or steel processes
- C21B2400/02—Physical or chemical treatment of slags
- C21B2400/022—Methods of cooling or quenching molten slag
- C21B2400/026—Methods of cooling or quenching molten slag using air, inert gases or removable conductive bodies
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B2400/00—Treatment of slags originating from iron or steel processes
- C21B2400/05—Apparatus features
- C21B2400/062—Jet nozzles or pressurised fluids for cooling, fragmenting or atomising slag
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B2400/00—Treatment of slags originating from iron or steel processes
- C21B2400/05—Apparatus features
- C21B2400/066—Receptacle features where the slag is treated
- C21B2400/072—Tanks to collect the slag, e.g. water tank
Definitions
- the invention relates to a method for atomizing metal melts, in which the liquid metal bath is sprayed from a tundish via an outlet opening by the aid of a gas into a cooling chamber, or onto a surface to be coated while compacting the comminuted particles by the aid of a propellant gas, as well as a device for carrying out said method.
- the invention aims to provide a method of the initially defined kind, by which it is feasible to atomize molten metals efficiently and by using substantially smaller-structured devices while substantially lowering the necessary amount of propellant gas, whereby a substantially finer atomization is to be ensured and the option to incorporate also other components into the atomized metal melt is to be provided, at the same time.
- the method according to the invention essentially consists in that the liquid metal melt via an annular gap is introduced into the outlet opening, into which a hot gas having a temperature of between 250° C. and 1300° C.
- a supercritical pressure of between 2 and 30 bars is ejected through a Laval nozzle concentrically with said opening, and that the hot gas is contacted with the melt bath at a speed exceeding supersonic speed, with a radial outwardly directed component or with a twist.
- the flow conditions of the hot gas streaming out through the Laval nozzle may also be adjusted in a manner so as to form an underexpanded propellant jet. This will subsequently result in pressure bursts in the range of Mach's nodes with expansion volumes lying between such Mach's nodes. Due to vibration interferences in the jet, shearing stresses will be introduced into the melt droplets, thus causing a rise in frequency with supercritical conditions increasing and a respective reduction of the distances of Mach's nodes in the axial direction of the propellant gas jet. The fact that an underexpanded jet is ejected causes an immediate expansion after the emergence from the nozzle.
- the distance to a surface to be coated may be chosen to be extremely short such that small-structured devices will do.
- the hot gas is ejected through a deflector body so as to enable the effective cross section of emergence from the Laval nozzle to be adapted to the respective requirements by a suitable adjustment of the deflector body.
- the use of a deflector body also serves to impart on the outflowing hot gas an appropriate additional flow component directed radially outwards and/or a twist.
- the method according to the invention is realized in a manner that a lance comprising the Laval nozzle for the hot gas is conducted concentrically in a tube while forming an annular space, and that reactive gases such as, e.g., CO, H 2 , O 2 or H 2 O vapor, and/or inert gases such as, e.g., N 2 or Ar, and/or carbides such as, e.g., WC, TiC or VC, are sucked in via said annular space.
- reactive gases such as, e.g., CO, H 2 , O 2 or H 2 O vapor, and/or inert gases such as, e.g., N 2 or Ar, and/or carbides such as, e.g., WC, TiC or VC
- the tube surrounding the lance with the Laval nozzle, by its lower edge defines the annular gap required for the access of the liquid metal melt, while an annular space is, at the time, formed between the lance and the tube for the aspiration of reactive gases and/or inert gases.
- Such a configuration allows for a preferred method control, by which metal powders or additives such as, e.g., SiC, Al 2 O 3 or Y 2 O 3 and/or carbides are charged into the aspirated gas flow, thus ensuring a high degree of adjustability of the atomizing process to different requirements by means of a particularly simple structural configuration of the device.
- the radiation heat of the metal melt ejected by the hot propellant gas and effectively atomized during ejection may be used to heat the hot gas, to which end it is preferably proceeded in a manner that the hot gas is heated in a heat exchanger surrounding the melt particles ejected.
- the desired jet geometry may be influenced, and adapted to the selected substances, in a simple manner by an appropriate axial displaceability of the hot gas nozzle, or of the deflector body, and/or an appropriate exchange of the deflector body.
- the process control according to the invention renders feasible the efficient atomization of any sort of metal melts while also enabling the atomization of alloys and, in particular, ferroalloys such as, for instance, FeV, FeCr, FeW, FeTi or FeMo.
- a pressure of 1.5 to 25 bars may be maintained within the tundish, while a pressure of 1.5 to 10 bars is preferably maintained in the cooling chamber.
- a melt saturated with pressure gas will be obtained, the pressure gas being comprised, for instance, of argon.
- the melt saturated with pressure gas facilitates disintegration, thus enabling an altogether finer atomization.
- the introduction of gas may be effected by means of bottom tuyeres of the tundish or via an immersion lance.
- the device according to the invention for carrying out said method includes a melt tundish and an immersion tube immersed in the melt while forming an annular gap surrounding the outlet opening for the melt, wherein a lance is further provided for the ejection of a propellant gas.
- the device according to the invention is essentially characterized in that the height-adjustable lance carries a Laval nozzle, wherein a deflector body is preferably arranged in a height-adjustable manner in the widening opening region of the Laval nozzle or following thereupon, viewed in the flow direction, the clear cross section between the nozzle and the deflector body being designed to increase in the axial direction towards the outlet end and to be larger than the narrowest cross section of the Laval nozzle.
- the deflector body provided in the widening opening region of the Laval nozzle, or following thereupon, viewed in the flow direction, may be adjusted on account of its height adjustability with a view to minimizing the consumption of propellant gas, wherein, in order to obtain the desired supersonic speed, it merely has to be taken care that the clear cross section between the inner wall of the Laval nozzle and the deflector body is designed to be always larger than the narrowest cross section of the Laval nozzle in the axial direction towards the outlet end and to increase in the axial direction.
- the lance opens in the outlet opening of the tundish below the lower edge of the immersion tube.
- the lance is arranged to be adjustable in height.
- the configuration advantageously is devised such that the outer diameter of the lance is smaller than the clear diameter of the immersion tube and the lance is sealingly guided through a lid of the immersion tube, and that a duct for the supply of gases and/or reactive metal powders and/or additives opens into the space of the immersion tube surrounding the lance.
- An adjustable throttle valve may be provided in the duct intended to supply gases and/or reactive metal powders, so that the volume between the lance and the immersion tube may optionally be maintained under a suitable negative pressure, pulsating flows, thus, being additionally obtainable. It is, however, also feasible to keep the valve completely closed.
- the deflector body is designed as a cone having deflector surfaces provided on its jacket.
- a distinctive radial component may be achieved by means of such a deflector body if, as in correspondence with a preferred configuration, the deflector surfaces extend in an S-likely curved manner and, in the peripheral direction, terminate so as to be directed at the tangent of the base circle of the conical body each under the same angle.
- FIG. 1 a melt tundish 1 in which a metal bath 2 is kept in the molten state is illustrated in cross section.
- an inductive heating may be provided, as is schematically indicated by coils 3 .
- a tube 4 is immersed in the metal bath, defining an annular gap between the bottom of the tundish 1 and the lower edge of the tube.
- This tube 4 is adjustable in the height direction in the sense of double arrow 5 so as to allow the amount of metal bath flowing off the tundish 1 per time unit to be regulated in a simple manner.
- the tube 4 is closed by a lid 6 in which a lance 7 is sealingly conducted in the sense of double arrow 8 so as to be adjustable in height.
- the lance 7 On its outlet end for hot gas, the lance 7 comprises a Laval nozzle 9 .
- a Laval nozzle By virtue of this configuration as a Laval nozzle, sonic speed will exactly adjust in the narrowest cross section of the Laval nozzle 9 if hot gas is supplied under supercritical conditions, supersonic speed being reached in the consecutive widening cross section on account of the rapid expansion occurring.
- a deflector body 10 which is also adjustable in the axial direction in the sense of double arrow 12 via an appropriate rod assembly 11 .
- Suitable adjustment of the deflector body may, thus, influence the jet shape, whereby it merely has to be safeguarded that the respectively effective cross section widens accordingly in the axial direction following the narrowest point of the Laval nozzle 9 so as to ensure the attainment of supersonic speed caused by the rapid expansion.
- the propellant gas jet emerging from the lance 7 then reaches a consecutively arranged cooling chamber 13 , in which a target 14 may, for instance, be provided.
- the propellant gas jet collides with the outflowing metal bath at supersonic speed and an appropriate viscosity on account of its high temperature so as to effect rapid and efficient comminution, which may be applied to the target 14 as a coating.
- the appropriately comminuted metal powder may be drawn off the cooling chamber 13 via a sluice 15 provided on its lower end.
- the radiation heat of the solidifying metal droplets may be exploited in a heat exchanger 16 surrounding the cooling chamber, to which cold gas is fed through a duct 17 and from which hot gas is drawn off through duct 18 . If the thus obtained temperature is sufficient for the desired purposes, this hot gas may be directly fed to the lance 7 via duct 18 . Further heating may be obtained by the aid of conventional recuperative heat exchangers not illustrated in the drawing.
- the lance 7 is guided at a distance from the inner wall of the tube 4 , leaving free an annular space 23 .
- Additional material may be sucked into this annular space via a duct 24 , said additional material comprising, above all, reactive gases like CO, H 2 , N 2 , O 2 or, if a partial oxidation of the metal particles is sought, also H 2 O vapor.
- the amount aspirated in each case may be determined by the aid of an adjustable throttle valve 25 .
- a number of powdery materials capable of flowing along with a gas stream may also be sucked into this duct from a reservoir 26 as doping agents.
- metal powders, SiC, Al 2 O 3 or even Y 2 O 3 may, above all, be aspirated and introduced via duct 24 into the annular space 23 , from which they are aspirated via the hot gas stream and rapidly brought into intensive contact with the metal melt.
- FIG. 2 depicts a modified configuration of the propellant gas lance, in which the lance 7 opens in the outlet opening of the tundish 1 below the lower edge of the immersion tube 4 .
- the lance comprises a Laval nozzle 9 , whereby the arrangement of a deflector body may be obviated. Attempts have shown that the atomization results are the better the deeper the propellant gas nozzle is inserted into the melt runout.
- Inert gases such as, for instance, nitrogen, argon and helium may, be envisaged as propellant gases in the first place, yet also reactive gases like CO, H 2 , optionally blended with water vapor, may be used depending on the set object, if an oxidative atomization is sought.
- Metal melts may comprise Al, Cu, Fe, Ni, Co, Ti, Mg melts or melts of rare earth metals or alloys thereof and, in particular, Co-based superalloys.
- the powders obtained are particularly suitable for applications in powder metallurgy, for instance for hot isostatic pressing, but also as a charging material for MIM processes (metal injection molding).
Abstract
In a method for atomizing metal melts, in which the liquid metal bath is sprayed from a tundish via an outlet opening by the aid of a gas into a cooling chamber, or onto a surface to be coated while compacting the comminuted particles by the aid of a propellant gas, the liquid metal melt via an annular gap is introduced into the outlet opening, into which a hot gas having a temperature of between 250° C. and 1300° C. and a supercritical pressure of between 2 and 30 bars is ejected through a Laval nozzle concentrically with said opening. The hot gas is contacted with the melt bath at a speed exceeding supersonic speed, with a radial outwardly directed component or with a twist.
The device for carrying out the method includes a melt tundish (1) and an immersion tube (4) immersed in the melt (2) while forming an annular gap surrounding the outlet opening for the melt (2) and a lance (7) for the ejection of a propellant gas, wherein the height-adjustable lance (7) carries a Laval nozzle (9).
Description
- The invention relates to a method for atomizing metal melts, in which the liquid metal bath is sprayed from a tundish via an outlet opening by the aid of a gas into a cooling chamber, or onto a surface to be coated while compacting the comminuted particles by the aid of a propellant gas, as well as a device for carrying out said method.
- In order to obtain dense metal coatings, it has already been proposed to eject such metals from a melt bath by the aid of propellant gases onto a surface to be coated or any other target with the still molten droplets solidifying during impingement on the surface to be coated or any other target (substrate), thus causing the coating to be accordingly compressed or compacted. When atomizing molten metals by the aid of propellants, an inert propellant gas jet is usually employed at ambient temperature, the known processes all requiring a relatively high propellant gas consumption and, as a rule, also a relatively high propellant gas pressure. A number of nozzle geometries have been proposed for the atomization and compaction of such atomized metal particles. The economy of such methods, as a rule, has, however, been substantially determined by the propellant gas amount and propellant gas pressure required.
- The invention aims to provide a method of the initially defined kind, by which it is feasible to atomize molten metals efficiently and by using substantially smaller-structured devices while substantially lowering the necessary amount of propellant gas, whereby a substantially finer atomization is to be ensured and the option to incorporate also other components into the atomized metal melt is to be provided, at the same time. To solve this object, the method according to the invention essentially consists in that the liquid metal melt via an annular gap is introduced into the outlet opening, into which a hot gas having a temperature of between 250° C. and 1300° C. and a supercritical pressure of between 2 and 30 bars is ejected through a Laval nozzle concentrically with said opening, and that the hot gas is contacted with the melt bath at a speed exceeding supersonic speed, with a radial outwardly directed component or with a twist. By using hot gases having temperatures of between 250° C. and 1300° C. and a supercritical pressure of between 2 and 30 bars as opposed to the known methods, the viscosity of the propellant gas is substantially increased in view of known methods, whereby shearing forces will act more efficiently and a finer comminution of the metal melt into particularly small particles having diameters d50 of below 10 μm will be obtained. At the same time, it is feasible to reduce the propellant gas consumption to ⅓ to ⅕ as against the use of propellant gases at the usually low temperatures, thus yielding substantial advantages as regards the economy of metal pulverization processes. Another advantage consists in that the metal melt does not freeze in the melt runout due to smaller temperature differences. By introducing the liquid melt via an annular gap into the outlet opening it has become feasible to influence the inflow of liquid melt and hence the flow rate per time unit in a simple manner by an appropriate adjustment of said annular gap, and by introducing the propellant gas concentrically with the outlet opening it has become feasible to use the structural component defining the annular gap as a second concentric tube, i.e., as a suction tube to suck in further substances. By contacting the hot gas with the melt bath at a speed exceeding sonic speed with a radial outwardly directed component or with a twist, which is feasible, in particular, by effecting the ejection under a supercritical pressure via a Laval nozzle, it is feasible to transmit high shearing forces at reduced propellant gas amounts, thus ensuring a particularly efficient and rapid comminution during the impingement on the metal melt by rapidly braking the propellant gas jet, which is more highly viscous on account of the elevated temperatures. By the hot gas being ejected in the interior of the melt jacket and contacted with the melt bath with a radially outwardly directed component, the gas is forced to pass through the melt jacket, thereby tearing the melt jacket open. This definitely brings about an essential advantage, which resides in the formation of a monogram powder, which formation is promoted by the radial tearing open of the hollow-cylindrical melt jacket. As the melt jacket is being torn open radially, it causes the formation of a uniform ligament in the radial direction and, after this, extremely uniform droplets. The monogram powder is excellently suitable for use in powder-metallurgical processes.
- The flow conditions of the hot gas streaming out through the Laval nozzle may also be adjusted in a manner so as to form an underexpanded propellant jet. This will subsequently result in pressure bursts in the range of Mach's nodes with expansion volumes lying between such Mach's nodes. Due to vibration interferences in the jet, shearing stresses will be introduced into the melt droplets, thus causing a rise in frequency with supercritical conditions increasing and a respective reduction of the distances of Mach's nodes in the axial direction of the propellant gas jet. The fact that an underexpanded jet is ejected causes an immediate expansion after the emergence from the nozzle. In a configuration of this type, the distance to a surface to be coated may be chosen to be extremely short such that small-structured devices will do. Advantageously, the hot gas is ejected through a deflector body so as to enable the effective cross section of emergence from the Laval nozzle to be adapted to the respective requirements by a suitable adjustment of the deflector body. The use of a deflector body also serves to impart on the outflowing hot gas an appropriate additional flow component directed radially outwards and/or a twist.
- Advantageously, the method according to the invention is realized in a manner that a lance comprising the Laval nozzle for the hot gas is conducted concentrically in a tube while forming an annular space, and that reactive gases such as, e.g., CO, H2, O2 or H2O vapor, and/or inert gases such as, e.g., N2 or Ar, and/or carbides such as, e.g., WC, TiC or VC, are sucked in via said annular space. The tube surrounding the lance with the Laval nozzle, by its lower edge defines the annular gap required for the access of the liquid metal melt, while an annular space is, at the time, formed between the lance and the tube for the aspiration of reactive gases and/or inert gases. Such a configuration allows for a preferred method control, by which metal powders or additives such as, e.g., SiC, Al2O3 or Y2O3 and/or carbides are charged into the aspirated gas flow, thus ensuring a high degree of adjustability of the atomizing process to different requirements by means of a particularly simple structural configuration of the device.
- The radiation heat of the metal melt ejected by the hot propellant gas and effectively atomized during ejection may be used to heat the hot gas, to which end it is preferably proceeded in a manner that the hot gas is heated in a heat exchanger surrounding the melt particles ejected.
- By using a hot gas, particularly small particles are formed as pointed out already in the beginning, thus leading to the formation of a flow of extremely fine particles, which is directed outwardly in a vortex-like manner, in the cooling chamber besides a downwardly directed flow. These extremely fine particles are again sucked into the downwardly directed flow of atomized melt, where they partially serve to rapidly cool the atomized melt. In order to reduce the portion of extremely fine particles which are effective for cooling, yet partially impede the efficient comminution of the particles, and, in particular, in order to ensure that such extremely fine particles will not cause caking in the region of the outlet opening or mouth of the tundish, it is advantageously proceeded in a manner that extremely fine particles of the solidifying melt, which ascend within the cooling chamber, are sucked off below the entry of the melt flow and discharged via a sluice. The option to suck in additional solid substances such as, for instance, silicon carbide, Al2O3 or Y2O3 in fine-powder form via the annular space, also allows for the obtainment of metal—matrix composite materials as well as ceramic—metal composite materials, and hence particularly wear-resistant coatings. Unlike with complex-design discrete spray nozzles, it is feasible by means of a single Laval nozzle and a consecutively arranged deflector body via which merely the hot propellant gas is ejected, to take into account all the set objects at a substantially reduced fuel consumption, the only thing required, in detail, being the appropriate adjustability of the tube to adjust the annular gap as well as the appropriate selection of the aspirated gases. Furthermore, the desired jet geometry may be influenced, and adapted to the selected substances, in a simple manner by an appropriate axial displaceability of the hot gas nozzle, or of the deflector body, and/or an appropriate exchange of the deflector body. In the main, the process control according to the invention renders feasible the efficient atomization of any sort of metal melts while also enabling the atomization of alloys and, in particular, ferroalloys such as, for instance, FeV, FeCr, FeW, FeTi or FeMo.
- According to a preferred process control, a pressure of 1.5 to 25 bars may be maintained within the tundish, while a pressure of 1.5 to 10 bars is preferably maintained in the cooling chamber. By observing these pressure levels, a melt saturated with pressure gas will be obtained, the pressure gas being comprised, for instance, of argon. The melt saturated with pressure gas facilitates disintegration, thus enabling an altogether finer atomization. The introduction of gas may be effected by means of bottom tuyeres of the tundish or via an immersion lance.
- The device according to the invention for carrying out said method includes a melt tundish and an immersion tube immersed in the melt while forming an annular gap surrounding the outlet opening for the melt, wherein a lance is further provided for the ejection of a propellant gas. The device according to the invention is essentially characterized in that the height-adjustable lance carries a Laval nozzle, wherein a deflector body is preferably arranged in a height-adjustable manner in the widening opening region of the Laval nozzle or following thereupon, viewed in the flow direction, the clear cross section between the nozzle and the deflector body being designed to increase in the axial direction towards the outlet end and to be larger than the narrowest cross section of the Laval nozzle. The deflector body provided in the widening opening region of the Laval nozzle, or following thereupon, viewed in the flow direction, may be adjusted on account of its height adjustability with a view to minimizing the consumption of propellant gas, wherein, in order to obtain the desired supersonic speed, it merely has to be taken care that the clear cross section between the inner wall of the Laval nozzle and the deflector body is designed to be always larger than the narrowest cross section of the Laval nozzle in the axial direction towards the outlet end and to increase in the axial direction. The arrangement of a deflector body is, however, not necessarily required, and it has turned out that an efficient atomization is feasible also without deflector body, particularly favorable results being achieved if, as in correspondence with a preferred further development of the device according to the invention, the lance opens in the outlet opening of the tundish below the lower edge of the immersion tube. To this end, the lance is arranged to be adjustable in height.
- In order to obtain an annular space suitable to suck in additional components, the configuration advantageously is devised such that the outer diameter of the lance is smaller than the clear diameter of the immersion tube and the lance is sealingly guided through a lid of the immersion tube, and that a duct for the supply of gases and/or reactive metal powders and/or additives opens into the space of the immersion tube surrounding the lance. An adjustable throttle valve may be provided in the duct intended to supply gases and/or reactive metal powders, so that the volume between the lance and the immersion tube may optionally be maintained under a suitable negative pressure, pulsating flows, thus, being additionally obtainable. It is, however, also feasible to keep the valve completely closed.
- Advantageously, the deflector body is designed as a cone having deflector surfaces provided on its jacket. A distinctive radial component may be achieved by means of such a deflector body if, as in correspondence with a preferred configuration, the deflector surfaces extend in an S-likely curved manner and, in the peripheral direction, terminate so as to be directed at the tangent of the base circle of the conical body each under the same angle.
- In the following, the invention will be explained in more detail by way of an exemplary embodiment of a device suitable to carry out the method according to the invention, which is schematically illustrated in the drawing.
- In FIG. 1, a melt tundish1 in which a
metal bath 2 is kept in the molten state is illustrated in cross section. In order to keep this metal bath in the molten state, an inductive heating may be provided, as is schematically indicated bycoils 3. - A
tube 4 is immersed in the metal bath, defining an annular gap between the bottom of the tundish 1 and the lower edge of the tube. Thistube 4 is adjustable in the height direction in the sense of double arrow 5 so as to allow the amount of metal bath flowing off the tundish 1 per time unit to be regulated in a simple manner. - The
tube 4 is closed by alid 6 in which alance 7 is sealingly conducted in the sense ofdouble arrow 8 so as to be adjustable in height. On its outlet end for hot gas, thelance 7 comprises a Lavalnozzle 9. By virtue of this configuration as a Laval nozzle, sonic speed will exactly adjust in the narrowest cross section of the Lavalnozzle 9 if hot gas is supplied under supercritical conditions, supersonic speed being reached in the consecutive widening cross section on account of the rapid expansion occurring. In this widening region is arranged adeflector body 10 which is also adjustable in the axial direction in the sense ofdouble arrow 12 via anappropriate rod assembly 11. Suitable adjustment of the deflector body may, thus, influence the jet shape, whereby it merely has to be safeguarded that the respectively effective cross section widens accordingly in the axial direction following the narrowest point of the Lavalnozzle 9 so as to ensure the attainment of supersonic speed caused by the rapid expansion. - The propellant gas jet emerging from the
lance 7 then reaches a consecutively arrangedcooling chamber 13, in which atarget 14 may, for instance, be provided. The propellant gas jet collides with the outflowing metal bath at supersonic speed and an appropriate viscosity on account of its high temperature so as to effect rapid and efficient comminution, which may be applied to thetarget 14 as a coating. In the absence of such atarget 14, the appropriately comminuted metal powder may be drawn off thecooling chamber 13 via asluice 15 provided on its lower end. The radiation heat of the solidifying metal droplets may be exploited in aheat exchanger 16 surrounding the cooling chamber, to which cold gas is fed through aduct 17 and from which hot gas is drawn off throughduct 18. If the thus obtained temperature is sufficient for the desired purposes, this hot gas may be directly fed to thelance 7 viaduct 18. Further heating may be obtained by the aid of conventional recuperative heat exchangers not illustrated in the drawing. - In the interior of the
cooling chamber 13, a furtherannular duct 19 is to be seen, via which extremely fine particles may be sucked off. These extremely fine particles may be supplied to a screening means 21 through aduct 20 and discharged as an extremely fine powder through asluice 22. The amount of extremely fine powder discharged, thus, will no longer get into the downwardly oriented flow and have no influence on the solidification behavior of the droplets comminuted by the propellant gas jet. - The
lance 7 is guided at a distance from the inner wall of thetube 4, leaving free anannular space 23. Additional material may be sucked into this annular space via aduct 24, said additional material comprising, above all, reactive gases like CO, H2, N2, O2 or, if a partial oxidation of the metal particles is sought, also H2O vapor. The amount aspirated in each case may be determined by the aid of anadjustable throttle valve 25. A number of powdery materials capable of flowing along with a gas stream may also be sucked into this duct from areservoir 26 as doping agents. As dispersible solids, metal powders, SiC, Al2O3 or even Y2O3 may, above all, be aspirated and introduced viaduct 24 into theannular space 23, from which they are aspirated via the hot gas stream and rapidly brought into intensive contact with the metal melt. - FIG. 2 depicts a modified configuration of the propellant gas lance, in which the
lance 7 opens in the outlet opening of thetundish 1 below the lower edge of theimmersion tube 4. The lance comprises aLaval nozzle 9, whereby the arrangement of a deflector body may be obviated. Attempts have shown that the atomization results are the better the deeper the propellant gas nozzle is inserted into the melt runout. - Inert gases such as, for instance, nitrogen, argon and helium may, be envisaged as propellant gases in the first place, yet also reactive gases like CO, H2, optionally blended with water vapor, may be used depending on the set object, if an oxidative atomization is sought.
- Metal melts may comprise Al, Cu, Fe, Ni, Co, Ti, Mg melts or melts of rare earth metals or alloys thereof and, in particular, Co-based superalloys. The powders obtained are particularly suitable for applications in powder metallurgy, for instance for hot isostatic pressing, but also as a charging material for MIM processes (metal injection molding).
Claims (14)
1. A method for atomizing metal melts, in which the liquid metal bath is sprayed from a tundish via an outlet opening by the aid of a gas into a cooling chamber, or onto a surface to be coated while compacting the comminuted particles by the aid of a propellant, characterized in that the liquid metal melt via an annular gap is introduced into the outlet opening, into which a hot gas having a temperature of between 250° C. and 1300° C. and a supercritical pressure of between 2 and 30 bars is ejected through a Laval nozzle concentrically with said opening, and that the hot gas is contacted with the melt bath at a speed exceeding supersonic speed, with a radial outwardly directed component or with a twist.
2. A method according to claim 1 , characterized in that the hot gas is ejected via a deflector body.
3. A method according to claim 1 or 2, characterized in that a lance comprising the Laval nozzle for the hot gas is conducted concentrically in a tube while forming an annular space, and that reactive gases such as, e.g., CO, H2, O2 or H2O vapor, and/or inert gases such as, e.g., N2 or Ar, and/or carbides such as, e.g., WC, TiC or VC, are sucked in via said annular space.
4. A method according to claim 3 , characterized in that reactive metal powders or additives such as, e.g., SiC, Al2O3 or Y2O3 are charged into the gas flow sucked in.
5. A method according to any one of claims 1 to 4 , characterized in that the hot gas is heated in a heat exchanger surrounding the melt particles ejected.
6. A method according to any one of claims 1 to 5 , characterized in that extremely fine particles of the solidifying melt, which ascend within the cooling chamber, are sucked off below the entry of the melt flow and discharged via a sluice.
7. A method according to any one of claims 1 to 6 , characterized in that a pressure of 1.5 to 25 bars is maintained within the tundish.
8. A method according to any one of claims 1 to 7 , characterized in that a pressure of 1.5 to 10 bars is maintained within the cooling chamber.
9. A device for carrying out the method according to any one of claims 1 to 8 , including a melt tundish (1) and an immersion tube (4) immersed in the melt (2) while forming an annular gap surrounding the outlet opening for the melt (2) and a lance (7) for the ejection of a propellant gas, characterized in that the height-adjustable lance (7) carries a Laval nozzle (9).
10. A device according to claim 9 , characterized in that a deflector body (10) is arranged in a height-adjustable manner in the widening opening region of the Laval nozzle (9) or following thereupon, viewed in the flow direction, the clear cross section between the nozzle (9) and the deflector body (10) being designed to increase in the axial direction towards the outlet end and to be larger than the narrowest cross section of the Laval nozzle (9).
11. A device according to claim 9 or 10, characterized in that the lance (7) opens in the outlet opening of the tundish (1) below the lower edge of the immersion tube (4).
12. A device according to any one of claims 9 to 11 , characterized in that the outer diameter of the lance (7) is smaller than the clear diameter of the immersion tube (4) and the lance (7) is sealingly guided through a lid (6) of the immersion tube (4), and that a duct (24) for the supply of gases and/or reactive metal powders and/or additives opens into the space of the immersion tube (4) surrounding the lance (7).
13. A device according to any one of claims 9 to 10 , characterized in that the deflector body (10) is designed as a cone having deflector surfaces provided on its jacket.
14. A device according to claim 13 , characterized in that the deflector surfaces extend in an S-likely curved manner and, in the peripheral direction, terminate so as to be directed at the tangent of the base circle of the conical body each under the same angle.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
ATA1169/2000 | 2000-07-07 | ||
AT0116900A AT410640B (en) | 2000-07-07 | 2000-07-07 | METHOD AND DEVICE FOR SPRAYING METAL MELT |
Publications (1)
Publication Number | Publication Date |
---|---|
US20020134198A1 true US20020134198A1 (en) | 2002-09-26 |
Family
ID=3686507
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/070,527 Abandoned US20020134198A1 (en) | 2000-07-07 | 2001-07-06 | Method and device for atomizing molten metals |
Country Status (8)
Country | Link |
---|---|
US (1) | US20020134198A1 (en) |
EP (1) | EP1299206A1 (en) |
JP (1) | JP2004502037A (en) |
AT (1) | AT410640B (en) |
AU (1) | AU2002218757A1 (en) |
IL (1) | IL148383A0 (en) |
WO (1) | WO2002004154A1 (en) |
ZA (1) | ZA200201752B (en) |
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6805726B1 (en) * | 1999-10-15 | 2004-10-19 | Applikations - Und Technikzentrum Fur Energieverfahrens- Umvelt- Und Stromungstechnik (Atz-Evus) | Method for producing a powder |
US20050188723A1 (en) * | 2002-08-29 | 2005-09-01 | Tribovent Verfahrensentwicklung Gmbh | Method and device for pulverizing and granulating melts |
WO2006104925A2 (en) * | 2005-03-29 | 2006-10-05 | Climax Engineered Materials, Llc | Metal powders and methods for producing the same |
US20090188789A1 (en) * | 2008-01-11 | 2009-07-30 | Climax Engineered Materials, Llc | Sodium/molybdenum powder compacts and methods for producing the same |
KR100983947B1 (en) * | 2010-05-26 | 2010-09-27 | 연규엽 | Manufacturing equipment of magmesium powder |
CN102712044A (en) * | 2009-12-15 | 2012-10-03 | 韩国机械研究院 | Production method and production device for a composite metal powder using the gas spraying method |
CN102847949A (en) * | 2012-09-27 | 2013-01-02 | 西北有色金属研究院 | Preparation method of spherical Ru-V powder brazing filler metal |
WO2014079797A2 (en) * | 2012-11-23 | 2014-05-30 | Siemens Vai Metals Technologies Gmbh | Slag granulation system and method of operation |
CN106001587A (en) * | 2016-06-30 | 2016-10-12 | 安泰科技股份有限公司 | Tundish for preparing iron-based water-atomized soft magnetic alloy powders and manufacturing method of tundish |
WO2016184455A1 (en) * | 2015-05-19 | 2016-11-24 | Technische Universität Bergakademie Freiberg | Device and method for atomizing molten materials |
US10661346B2 (en) | 2016-08-24 | 2020-05-26 | 5N Plus Inc. | Low melting point metal or alloy powders atomization manufacturing processes |
US11185920B2 (en) | 2018-01-12 | 2021-11-30 | Hammond Group, Inc. | Methods and systems for making metal-containing particles |
US11607732B2 (en) | 2018-02-15 | 2023-03-21 | 5N Plus Inc. | High melting point metal or alloy powders atomization manufacturing processes |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR101143888B1 (en) * | 2009-12-15 | 2012-05-11 | 한국기계연구원 | The method for preparation of metal matrix powder with mechanical alloying and metal matrix powder thereby |
KR101143887B1 (en) * | 2009-12-15 | 2012-05-11 | 한국기계연구원 | The method for preparation of metal matrix powder using gas atomization and metal matrix powder thereby |
AT518979B1 (en) * | 2016-11-15 | 2018-03-15 | Radmat Ag | Process and device for working up a melt containing iron oxide and phosphorous oxides |
CN113145853B (en) * | 2021-04-22 | 2023-04-18 | 鞍钢股份有限公司 | Gas atomization preparation device and method for spherical metal powder |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6660223B2 (en) * | 2000-02-22 | 2003-12-09 | Holcim Ltd. | Device for atomizing liquid melts |
Family Cites Families (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CH215365A (en) * | 1938-11-11 | 1941-06-30 | Glasfasern A G | Method and device for the production of fibers from glass, slag or similar substances that are plastic in heat. |
AT309962B (en) * | 1971-05-13 | 1973-09-10 | Mannesmann Ag | Process and apparatus for the manufacture of metal powder |
DE2126856B2 (en) * | 1971-05-27 | 1972-11-23 | Mannesmann AG, 4000 Düsseldorf | METAL POWDER MANUFACTURING METAL PROCESS AND DEVICE |
GB1413651A (en) * | 1971-11-04 | 1975-11-12 | Singer A R E | Atomising of metals |
US4619845A (en) * | 1985-02-22 | 1986-10-28 | The United States Of America As Represented By The Secretary Of The Navy | Method for generating fine sprays of molten metal for spray coating and powder making |
DE3533964C1 (en) * | 1985-09-24 | 1987-01-15 | Alfred Prof Dipl-Ing Dr-I Walz | Method and device for producing fine powder in spherical form |
US4671994A (en) * | 1986-02-10 | 1987-06-09 | Materials Technology Corporation | Method for producing fiber reinforced hollow microspheres |
GB8622949D0 (en) * | 1986-09-24 | 1986-10-29 | Alcan Int Ltd | Alloy composites |
US5019686A (en) * | 1988-09-20 | 1991-05-28 | Alloy Metals, Inc. | High-velocity flame spray apparatus and method of forming materials |
DE4019563A1 (en) * | 1990-06-15 | 1991-12-19 | Mannesmann Ag | Prodn. of e.g. iron powder by atomising cast melt stream - using gaseous phase of liquid droplets esp. water to effect atomisation |
DE4132693A1 (en) * | 1991-10-01 | 1993-04-08 | Messer Griesheim Gmbh | METHOD AND DEVICE FOR PRODUCING POWDERS |
DE4340102C2 (en) * | 1993-11-22 | 1996-12-12 | Mannesmann Ag | Device for atomizing metal melts, in particular for the production of metal powder or metal objects |
DE19758111C2 (en) * | 1997-12-17 | 2001-01-25 | Gunther Schulz | Method and device for producing fine powders by atomizing melts with gases |
AT406262B (en) * | 1998-06-29 | 2000-03-27 | Holderbank Financ Glarus | METHOD AND DEVICE FOR GRANULATING AND CRUSHING LIQUID SLAG |
AT407247B (en) * | 1998-12-01 | 2001-01-25 | Holderbank Financ Glarus | METHOD FOR GRANULATING LIQUID SLAG MOLDS AND DEVICE FOR CARRYING OUT THIS METHOD |
-
2000
- 2000-07-07 AT AT0116900A patent/AT410640B/en not_active IP Right Cessation
-
2001
- 2001-07-06 JP JP2002508596A patent/JP2004502037A/en active Pending
- 2001-07-06 EP EP01984153A patent/EP1299206A1/en not_active Withdrawn
- 2001-07-06 IL IL14838301A patent/IL148383A0/en unknown
- 2001-07-06 WO PCT/AT2001/000225 patent/WO2002004154A1/en not_active Application Discontinuation
- 2001-07-06 US US10/070,527 patent/US20020134198A1/en not_active Abandoned
- 2001-07-06 AU AU2002218757A patent/AU2002218757A1/en not_active Abandoned
-
2002
- 2002-03-01 ZA ZA200201752A patent/ZA200201752B/en unknown
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6660223B2 (en) * | 2000-02-22 | 2003-12-09 | Holcim Ltd. | Device for atomizing liquid melts |
Cited By (28)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6805726B1 (en) * | 1999-10-15 | 2004-10-19 | Applikations - Und Technikzentrum Fur Energieverfahrens- Umvelt- Und Stromungstechnik (Atz-Evus) | Method for producing a powder |
US7240520B2 (en) * | 2002-08-29 | 2007-07-10 | Holcim Ltd. | Method and device for pulverizing and granulating melts |
US20050188723A1 (en) * | 2002-08-29 | 2005-09-01 | Tribovent Verfahrensentwicklung Gmbh | Method and device for pulverizing and granulating melts |
US20080264204A1 (en) * | 2005-03-29 | 2008-10-30 | Climax Engineered Materials, Llc | Metal Powders and Methods for Producing the Same |
US20060219056A1 (en) * | 2005-03-29 | 2006-10-05 | Larink Steven C Jr | Metal powders and methods for producing the same |
WO2006104925A3 (en) * | 2005-03-29 | 2008-01-17 | Climax Engineered Mat Llc | Metal powders and methods for producing the same |
US8206485B2 (en) | 2005-03-29 | 2012-06-26 | Climax Engineered Material, LLC | Metal powders and methods for producing the same |
US20080271567A1 (en) * | 2005-03-29 | 2008-11-06 | Climax Engineered Materials, Llc | Metal Powders and Methods for Producing the Same |
US7470307B2 (en) | 2005-03-29 | 2008-12-30 | Climax Engineered Materials, Llc | Metal powders and methods for producing the same |
WO2006104925A2 (en) * | 2005-03-29 | 2006-10-05 | Climax Engineered Materials, Llc | Metal powders and methods for producing the same |
US7824465B2 (en) | 2005-03-29 | 2010-11-02 | Climax Engineered Materials, Llc | Methods for producing metal powders |
US20090188789A1 (en) * | 2008-01-11 | 2009-07-30 | Climax Engineered Materials, Llc | Sodium/molybdenum powder compacts and methods for producing the same |
US8197885B2 (en) | 2008-01-11 | 2012-06-12 | Climax Engineered Materials, Llc | Methods for producing sodium/molybdenum power compacts |
CN102712044A (en) * | 2009-12-15 | 2012-10-03 | 韩国机械研究院 | Production method and production device for a composite metal powder using the gas spraying method |
US9267190B2 (en) | 2009-12-15 | 2016-02-23 | Korea Institute Of Machinery And Materials | Production method and production device for a composite metal powder using the gas spraying method |
US8632326B2 (en) | 2010-05-26 | 2014-01-21 | Kyu Yeub Yeon | Manufacturing device of spherical magnesium fine powder |
KR100983947B1 (en) * | 2010-05-26 | 2010-09-27 | 연규엽 | Manufacturing equipment of magmesium powder |
CN102847949A (en) * | 2012-09-27 | 2013-01-02 | 西北有色金属研究院 | Preparation method of spherical Ru-V powder brazing filler metal |
RU2633118C2 (en) * | 2012-11-23 | 2017-10-11 | Прайметалз Текнолоджиз Аустриа ГмбХ | Slag granulation system and operation method |
WO2014079797A2 (en) * | 2012-11-23 | 2014-05-30 | Siemens Vai Metals Technologies Gmbh | Slag granulation system and method of operation |
WO2014079797A3 (en) * | 2012-11-23 | 2014-07-31 | Siemens Vai Metals Technologies Gmbh | Slag granulation system and method of operation |
WO2016184455A1 (en) * | 2015-05-19 | 2016-11-24 | Technische Universität Bergakademie Freiberg | Device and method for atomizing molten materials |
CN106001587A (en) * | 2016-06-30 | 2016-10-12 | 安泰科技股份有限公司 | Tundish for preparing iron-based water-atomized soft magnetic alloy powders and manufacturing method of tundish |
US10661346B2 (en) | 2016-08-24 | 2020-05-26 | 5N Plus Inc. | Low melting point metal or alloy powders atomization manufacturing processes |
US11453056B2 (en) | 2016-08-24 | 2022-09-27 | 5N Plus Inc. | Low melting point metal or alloy powders atomization manufacturing processes |
US11185920B2 (en) | 2018-01-12 | 2021-11-30 | Hammond Group, Inc. | Methods and systems for making metal-containing particles |
US11185919B2 (en) | 2018-01-12 | 2021-11-30 | Hammond Group, Inc. | Methods and systems for forming mixtures of lead oxide and lead metal particles |
US11607732B2 (en) | 2018-02-15 | 2023-03-21 | 5N Plus Inc. | High melting point metal or alloy powders atomization manufacturing processes |
Also Published As
Publication number | Publication date |
---|---|
ZA200201752B (en) | 2003-06-02 |
ATA11692000A (en) | 2002-11-15 |
AU2002218757A1 (en) | 2002-01-21 |
WO2002004154A1 (en) | 2002-01-17 |
EP1299206A1 (en) | 2003-04-09 |
AT410640B (en) | 2003-06-25 |
JP2004502037A (en) | 2004-01-22 |
IL148383A0 (en) | 2002-09-12 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20020134198A1 (en) | Method and device for atomizing molten metals | |
US4272463A (en) | Process for producing metal powder | |
CA1228459A (en) | Device and process for atomising liquid metals for the purpose of producing a finely granular powder | |
EP0504382B1 (en) | A melt atomizing nozzle and process | |
Li et al. | Fine spherical powder production during gas atomization of pressurized melts through melt nozzles with a small inner diameter | |
EP0834585A1 (en) | A method for producing a chromium carbide-nickel chromium atomized powder | |
US4613371A (en) | Method for making ultrafine metal powder | |
WO1999011407A1 (en) | Method of producing metal powder by atomizing and apparatus therefor | |
Gummeson | Modern atomizing techniques | |
US4687510A (en) | Method for making ultrafine metal powder | |
CA1078567A (en) | Atomization | |
US7628838B2 (en) | Method for producing particle-shaped material | |
CA2384120A1 (en) | Method and device for atomizing molten metals | |
US4971133A (en) | Method to reduce porosity in a spray cast deposit | |
Schade et al. | Atomization | |
EP0543017B1 (en) | Method and device for making metallic powder | |
Dixon | Atomizing molten metals—a review | |
JP2969754B2 (en) | Metal powder production equipment | |
US6803016B2 (en) | Device for atomizing and granulating liquid slags | |
JPH07102307A (en) | Production of flaky powder material | |
WO1989000470A1 (en) | Double disintegration powder method | |
US7309375B2 (en) | Method for producing metallic powders consisting of irregular particles | |
Khor | Production of fine metal and ceramic powders by the plasma melt and rapid solidification (PMRS) process | |
JP2528333B2 (en) | Liquid spray method | |
Cheney | Plasma-Melted and Rapidly-Solidified Powders |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: TRIBOVENT VERFAHRENSENTWICKLUNG GMBH, AUSTRIA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:EDLINGER, ALFRED;REEL/FRAME:012878/0905 Effective date: 20020214 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |