EP2944401B1 - Method for producing a component from a metallic alloy containing an amorphous phase - Google Patents

Description

The invention relates to a method for producing a component from an at least partially amorphous metal alloy.

The invention further relates to a component made of a metal alloy with amorphous phase and the use of such a component.

Amorphous metals and their alloys have been known for several decades. Thin tapes and their manufacture are disclosed, for example, in the disclosure DE 35 24 018 A1 described, wherein on a support by quench cooling from the molten phase, a thin metallic glass is produced. Also, for example, in the patent EP 2 430 205 B1 described a composite of an amorphous alloy, which requires a cooling rate of 102 K / s for its production. The disadvantage of this is that with such known methods only thin layers or very compact components can be constructed with a few millimeters in cross-section.

One problem therefore is to produce large components in complex shapes that have an amorphous structure. The necessary cooling rates are not technically feasible for complex components and semi-finished products with large volumes. From the WO 2008/039134 A1 For example, a method is known in which a larger component is made of an amorphous metal powder. For this purpose, the component is built up in layers in the manner of a 3D printing, wherein partial areas of the layers are melted with an electron beam.

The disadvantage of this is that the method is very expensive and expensive to implement. In addition, with such a method, it is not possible to achieve sufficient homogeneity of the physical properties of the component produced. The local melting and again cooling of the powder leads to a punctual exceeding of the crystallization temperature and a crystallization of the alloy if the cooling rate of the melt is too low. This results in an undesirable amount and an uneven distribution of crystalline phase in the component.

EP 1 593 749 A1 describes a metallic glass of an iron alloy containing 0.5-10 at% Ga, 7-15 at% P, 3-7 at% C, 3-7 at% B and 1-7 at% Si as Contains alloying elements and is present in the form of spherical particles. The spherical ones Metal particles are available via gas atomization and are used for the production of a sintered body.

The object of the invention is therefore to overcome the disadvantages of the prior art. In particular, a simple and inexpensive to implement method is to be developed with which a component can be made of a metal alloy with amorphous portion, which may have a volume of 0.1 cm ³ and more, preferably 1 cm ³ and more, and in different Even complex shapes can be generated. The component produced should also have the highest possible homogeneity with regard to the physical properties and the distribution of the amorphous phase. Object of the present invention is also to provide such a component. The process should be easy to implement and deliver highly reproducible results. The component produced should have the highest possible proportion of amorphous metallic phase. It is also desirable if the component produced is as compact as possible and has only a few pores. Another object can be seen that the method can be implemented with the largest possible number of different alloys having an amorphous phase. Furthermore, it is advantageous if the method can be implemented with the simplest and most commonly used in laboratories equipment and tools.

1. A) Bereitstellen eines Pulvers aus einer zumindest teilweise amorphen Metalllegierung, wobei das Pulver aus sphärischen Pulverpartikeln besteht, wobei die sphärischen Pulverpartikel eine abgerundete zumindest näherungsweise kugelförmige Form aufweisen und ein Verhältnis des längsten Querschnitts zum kürzesten Querschnitt von höchstens 2 zu 1 haben und wobei als Durchmesser der größte Querschnitt der Pulverpartikel angenommen wird, und die Pulverpartikel einen Durchmesser von weniger als 125 µm aufweisen, und wobei das Pulver weniger als 1 Gewichtsprozent an Teilchen mit einem Durchmesser kleiner als 5 µm aufweist oder das Pulver gesiebt oder durch Windsichten behandelt wird, so dass es weniger als 1 Gewichtsprozent an Teilchen mit einem Durchmesser kleiner als 5 µm aufweist;
2. B) Pressen des Pulvers in die gewünschte Form des zu erzeugenden Bauteils;
3. C) Verdichten und Sintern des Pulvers durch eine Temperaturbehandlung des Pulvers während des Pressens oder nach dem Pressen bei einer Temperatur, die zwischen der Transformationstemperatur und der Kristallisationstemperatur der amorphen Phase der Metalllegierung liegt, wobei die Dauer der Temperaturbehandlung derart gewählt wird, dass das Bauteil nach der Temperaturbehandlung gesintert ist und einen amorphen Anteil von mindestens 85 Prozent aufweist.

The objects of the invention are achieved by a method for producing a component from an at least partially amorphous metal alloy with the steps:

1. A) providing a powder of an at least partially amorphous metal alloy, wherein the powder consists of spherical powder particles, wherein the spherical powder particles have a rounded at least approximately spherical shape and a ratio of the longest cross section to the shortest cross section of at most 2 to 1 and wherein as a diameter the largest cross section of the powder particles is assumed, and the powder particles have a diameter of less than 125 microns, and wherein the powder less than 1 weight percent of particles having a diameter smaller than 5 microns or the powder is sieved or treated by air classification, so that it has less than 1% by weight of particles smaller than 5 μm in diameter;
2. B) pressing the powder into the desired shape of the component to be produced;
3. C) compacting and sintering the powder by a temperature treatment of the powder during pressing or after pressing at a temperature which is between the transformation temperature and the crystallization temperature of the amorphous phase of the metal alloy, wherein the duration of the temperature treatment is selected so that the component after the heat treatment is sintered and has an amorphous content of at least 85 percent.

The duration of the temperature treatment is chosen such that the duration is at least so long that the powder is sintered after the temperature treatment, and that the duration is at most so long that the component still has an amorphous content of at least 85 percent after the temperature treatment.

The powder consists of powder particles of which 100% are less than 125 μm in diameter. Such particle sizes or particle distributions are often also denoted by D ₁₀₀ = 125 μm.

In physics and chemistry, an amorphous material is a substance in which the atoms do not form ordered structures but form an irregular pattern and have only short-range order, but not long-range ordering. In contrast to amorphous, regularly structured materials are called crystalline.

Spherical particles need not be geometrically perfect spheres within the meaning of the present invention, but may also deviate from the spherical shape. The spherical powder particles have a rounded at least approximately spherical shape and have a ratio of the longest cross section to the shortest cross section of at most 2 to 1. For the purposes of the present invention, a spherical geometry does not mean a strictly geometrical or mathematical sphere. The cross-sections relate to running within the powder particles extremale dimensions. Particularly preferred spherical powder particles may have a ratio of the longest cross section to the shortest cross section of at most 1.5 to 1, or most preferably spherical. In this case, the diameter of the largest cross-section of the powder particles is assumed according to the invention.

• Es kann eine hohe Schüttdichte des Pulvers erreicht werden;
• Die Pulverpartikel weisen ähnlich gekrümmte Oberflächen auf, die bei der

The spherical shape of the powder particles has the following advantages:

• It can be achieved a high bulk density of the powder;
• The powder particles have similar curved surfaces, which in the

Temperature treatment under the same conditions (temperature and time or the same heat energy input) soft - or at least under soft approximate the same conditions soft. As a result, they combine or sinter these particularly well and within a short period of time, or at a known time or in a known time interval, with adjacent powder particles. Another advantage of high bulk density is low shrinkage of the component during sintering. As a result, production close to the final shape is possible.

The component may, in accordance with a preferred embodiment of the present invention, be considered to be sintered in particular if it has a density of at least 97% of the theoretical density of the completely amorphous metal alloy.

In the context of the present invention, sintering or sintering is understood as meaning a process in which the powder particles soften on the surface and combine with one another and remain connected after cooling. As a result, a coherent body or a coherent component is generated from the powder.

The transformation temperature of an amorphous phase is often referred to as the glass transition temperature or as a transformation point or glass transition point, it being understood that these are equivalent terms for the transformation temperature.

Preferably, the powder is formed by filling the powder into a mold or into a tool and then pressing the powder in the mold or in the tool or by pressing it with the tool.

The heating until reaching the transformation temperature and the cooling should be carried out according to the invention as quickly as possible, since even at these temperatures below the transformation temperature crystallization takes place on the inevitable seed crystals, but still no softening of the powder particles is achieved, leading to sintering of the powder could lead. It is to be achieved according to the invention a plastic deformation of the powder particles, which leads to a compacting of the powder and thus to an accelerated sintering of the powder. An overshoot of the temperature above the desired setpoint temperature or final temperature should be as low as possible.

The powder particle size of the powder or the powder particle size distribution of the powder can be achieved by the manufacturing process and by sieving a starting powder. The powder provided according to the invention is thus produced by sieving a starting powder before it is provided or used for the process according to the invention. In addition, by sieving, it can also be ensured that the number of powder particles having a shape which differs greatly from the spherical shape, which are produced by sintering several powder particles and which are contained in the starting powder, can be reduced or minimized.

With the invention is also proposed as a preferred embodiment of the method that the temperature treatment is carried out under vacuum, wherein preferably the powder is compacted by a temperature treatment at a vacuum of at least 10 ^-3 mbar.

This ensures that the surface of the powder can react less strongly with the surrounding gases. Namely, metal oxides and other reaction products, as nucleating agents for crystalline phases, have a negative effect on the purity of the amorphous phase in the produced component.

For the same reason, the invention may additionally or alternatively be provided that the temperature treatment is carried out under a protective gas, in particular under a noble gas such as argon, preferably with a purity of at least 99.99%, more preferably with a purity of at least 99.999 % he follows. It may preferably be provided in such embodiments that the atmosphere in which the pressing and the temperature treatment or only the temperature treatment takes place is largely freed of residual gases by repeated evacuation and rinsing with inert gas, in particular with argon.

It can alternatively be provided according to the invention that the temperature treatment takes place under a reducing gas, in particular under a forming gas, in order to keep the amount of interfering metal oxides as low as possible.

Another measure for reducing the number of metal oxides in the component can be achieved by the use of an oxygen getter in the temperature treatment of the powder and / or in the production of the powder.

Furthermore, it can be provided according to the invention that the powder is compacted by hot isostatic pressing or hot pressing.

The combination of pressure and temperature treatment results in a more compact component. In addition, the compound is improved by the plastic deformation of the powder particles with each other and accelerates the sintering behavior, so that a shorter duration of the temperature treatment can be selected and the proportion of crystalline phase is reduced in the component.

According to a development of the invention, it can also be provided that the duration of the temperature treatment is selected such that the component has an amorphous content of at least 90 percent, preferably of more than 95 percent, particularly preferably more than 98 percent.

The higher the proportion of the amorphous phase in the component, the more one approaches the desired physical properties of a fully amorphous phase component.

Preferred embodiments of the present invention may also provide that a powder of an amorphous metal alloy or an at least partially amorphous metal alloy having at least 50 weight percent zirconium is used.

Zirconium-containing amorphous metal alloys are particularly well suited for practicing methods of the present invention because many of these alloys have a large difference between the transformation temperature and the crystallization temperature, making the process easier to implement.

1. a) 58 bis 77 Gewichtsprozenten Zirkonium,
2. b) 0 bis 3 Gewichtsprozenten Hafnium,
3. c) 20 bis 30 Gewichtsprozenten Kupfer,
4. d) 2 bis 6 Gewichtsprozenten Aluminium, und
5. e) 1 bis 3 Gewichtsprozenten Niob

bereitgestellt wird.Very particularly preferred embodiments of the present invention may provide that a powder of an amorphous metal alloy or an at least partially amorphous metal alloy

1. a) 58 to 77% by weight zirconium,
2. b) 0 to 3% by weight hafnium,
3. c) 20 to 30% by weight of copper,
4. d) 2 to 6 weight percent aluminum, and
5. e) 1 to 3 weight percent niobium

provided.

The remainder up to 100 percent by weight is zirconium. Common contaminants may be included in the alloy. These zirconium-containing amorphous metal alloys are particularly well suited for implementing inventive methods.

Furthermore, it can be provided that the spherical amorphous metal alloy powder is produced by melt atomization, preferably by melt atomization in a noble gas, in particular in argon, particularly preferably by melt atomization in a noble gas of purity 99.99%, 99.999% or higher purity. In the context of the present invention, an amorphous metal alloy is also used if the metal alloy has an amorphous phase content of at least 85% by volume.

The preparation of the powder is of course prior to the provision of the powder. By melt atomization powder particles can be produced with spherical shape in a simple and cost-effective manner. The use of inert gas, in particular of argon or high-purity argon in the melt atomization causes that in the powder as few disturbing impurities as metal oxides are included.

The powder has less than 1 weight percent of particles less than 5 microns in diameter, or the powder is screened or air-treated so that it has less than 1 weight percent of particles less than 5 microns in diameter.

According to the invention, powder particles with a diameter of less than 5 μm are preferably removed by air classification, or more precisely, the proportion of powder particles with a diameter of less than 5 μm is reduced by air classification.

Due to the low proportion of powder particles with a diameter smaller than 5 .mu.m, the surface of the powder which is sensitive to oxidation or to another disturbing chemical reaction of the powder particles with surrounding gas (sum of the surfaces of all powder particles) is limited. Furthermore, by limiting the grain size of the powder, it is ensured that the softening of the powder particles will take place under similar conditions (in terms of temperature and time or energy input), since the curvatures of the surfaces of the powder particles will then be similar and thus compact Filling of the powder can be achieved by pressing. A small proportion of fine powder particles (less than 5 microns) does not adversely affect, since such powder particles can be stored in the interstices between larger particles and thus increase the density of the unsintered powder.

With a preferred development of the method according to the invention, it is proposed that the temperature treatment of the powder takes place at a temperature (T) between the transformation temperature and a maximum temperature, the maximum temperature being 30% higher than the temperature difference between the transformation temperature (T _T ) and the crystallization temperature (T _K ) of the amorphous phase of the metallic alloy is above the transformation temperature (T _T ), the maximum temperature preferably being 20% or 10% of the temperature difference between the transformation temperature (T _T ) and the crystallization temperature (T _K ) the amorphous phase of the metallic alloy is above the transformation temperature (T _T ).

oder bevorzugt $${\mathrm{T}}_{\mathrm{T}}<\mathrm{T}<{\mathrm{T}}_{\mathrm{T}}+\left(20/100\right)*\left({\mathrm{T}}_{\mathrm{K}}-{\mathrm{T}}_{\mathrm{T}}\right)$$

oder besonders bevorzugt $${\mathrm{T}}_{\mathrm{T}}<\mathrm{T}<{\mathrm{T}}_{\mathrm{T}}+\left(10/100\right)*\left({\mathrm{T}}_{\mathrm{K}}-{\mathrm{T}}_{\mathrm{T}}\right).$$

If the temperature treatment is close to or above the transformation temperature, the formation and growth of the crystalline phase will be relatively low, and thus the purity of the amorphous phase in the component will be high. Expressed as a formula, the temperature T at which the temperature treatment of the powder takes place, based on the transformation temperature T _T and the crystallization temperature T _{K of} the amorphous phase of the metallic alloy, should fulfill the following conditions: $${\mathrm{T}}_{\mathrm{T}}<\mathrm{T}<{\mathrm{T}}_{\mathrm{T}}+\left(300/100\right)*\left({\mathrm{T}}_{\mathrm{K}}-{\mathrm{T}}_{\mathrm{T}}\right)$$

or preferred $${\mathrm{T}}_{\mathrm{T}}<\mathrm{T}<{\mathrm{T}}_{\mathrm{T}}+\left(20/100\right)*\left({\mathrm{T}}_{\mathrm{K}}-{\mathrm{T}}_{\mathrm{T}}\right)$$

or more preferably $${\mathrm{T}}_{\mathrm{T}}<\mathrm{T}<{\mathrm{T}}_{\mathrm{T}}+\left(10/100\right)*\left({\mathrm{T}}_{\mathrm{K}}-{\mathrm{T}}_{\mathrm{T}}\right),$$

With the temperature ranges specified in the preceding mathematical formulas, in which the temperature treatment is to take place, sintering is achieved with little formation of crystalline phases in the component.

A particularly advantageous embodiment of the method according to the invention results if it is provided that the duration of the temperature treatment is selected as a function of the geometric shape, in particular the thickness, of the component to be produced, preferably as a function of the largest relevant diameter of the component to be produced ,

The geometric shape, or the thickness, of the component to be produced is taken into account in that the heat conduction in the molded powder or molding component should be sufficient to also the powder inside the component or the component inside up to the transformation temperature or above Heat transformation temperature, so that also takes place inside the component sintering of the powder.

The largest relevant diameter of the component can be geometrically determined by the largest sphere that can be geometrically accommodated within the component. When determining the largest relevant diameter, it is possible to disregard channels or gaps in the body which do not or only slightly contribute to the heat input via a surrounding gas and / or another heat source (for example in the sum of less than 5%).

Preferably, it may be provided that the duration of the heat treatment in a time range of 3 seconds per millimeter of the thickness or the wall thickness of the component or the largest relevant diameter of the component to be produced to 900 seconds per millimeter of thickness or the largest relevant diameter of the Component takes place, wherein preferably the duration of the temperature treatment in a time range of 5 seconds per millimeter of the thickness or the wall thickness of the component or the largest relevant diameter of the component to be produced to 600 seconds per millimeter of thickness or the largest relevant diameter of the component to be produced he follows.

By taking into account the shape, the thickness, or the wall thickness of the component, and / or the largest relevant diameter of the component, the duration of the temperature treatment is selected so that sufficient sintering of the powder occurs, but at the same time as possible the formation of crystalline phase in the component is kept low or ideally minimal. For certain components and for some applications, it may already be sufficient if only the edge regions of the component are completely sintered and powder that is not yet sintered is present in the interior of the component. Preferably, however, the component is sintered completely (also inside).

The objects underlying the present invention are also achieved by a component made of a pressed, sintered, spherical, amorphous Metal alloy powder, wherein the component has an amorphous content of at least 85 percent.

The component is produced by the method according to the invention. The method according to the invention has been described above.

The objects underlying the invention are also achieved by the use of such a component as a gear, friction wheel, wear-resistant component, housing, watch case, part of a transmission or semi-finished.

The invention is based on the surprising finding that by using spherical powder particles of suitable size and a temperature treatment at the suitable temperature over a suitable short period, it is also possible to produce larger and / or complex components from a powder of an amorphous metal alloy consist of a high proportion (at least 85 percent by volume) of the amorphous phase and thus have advantageous physical properties of the amorphous metal alloy. The present invention thus describes for the first time a method in which a component of an amorphous metal alloy or of a metal alloy consisting of at least 85% of an amorphous phase can be produced by sintering a powder in which a high proportion of amorphous phase is retained. Preferably, the duration of the temperature treatment is adapted to the dimensions of the component to be produced in order to obtain the highest possible proportion of amorphous phase during sintering of the powder, or to keep the proportion of crystalline phase in the metal alloy as low as possible. For the same purpose, it is advantageous to carry out the temperature treatment under protective gas or under vacuum in order to produce as small as possible a proportion of metal oxides or other reaction products with air in the powder and thus in the component. Such metal oxides and other reaction products act in particular as nuclei for the crystallization and thus reduce the proportion of amorphous phase in the component.

It has been found within the scope of the present invention that processes according to the invention lead to particularly good results when the amorphous metallic powders for producing the component are produced by melt atomization and the powders are X-ray amorphous, with their powder particles preferably being smaller than 125 μm. In the melt atomization, the resulting molten Droplets of the alloy cooled very rapidly through the process gas stream (argon), thereby promoting the presence of an amorphous powder fraction. From this powder, the fine dust (particles smaller than 5 microns) and the coarse grain of greater than 125 microns largely separated, for example by sieving and / or by air classification of the powder. Such powder fractions are then an optimum starting material (the powder provided) to produce complex amorphous components by pressing and temperature treatment, both successive or combined pressure and temperature steps having very good results with respect to the amorphous behavior of the component. With powders produced in this way, a component with a particularly high proportion of amorphous metallic phase is obtained. At the same time, the component thus produced and made of such a powder has a high degree of sintered powder particles and a low porosity, preferably a porosity of less than 5%.

It is important that in the process, the amorphous powder is not heated to the crystallization temperature or beyond, otherwise crystallization occurs and the amorphous character of the alloy is lost. On the other hand, it is necessary to heat the material at least to the transformation temperature, ie the temperature at which the amorphous phase of the metal alloy during the cooling from the plastic region in the rigid state passes. In this temperature range, the powder particles can connect, but without crystallizing. The transformation temperature can also be referred to as the glass transition temperature and is often referred to as such.

However, since it is technically hardly possible and economically not sensible to be absolutely free of impurities and also free of oxygen in particular, microcrystalline inclusions can not be avoided. Low levels of oxygen in the two-digit ppm range cause corresponding oxide formation of the oxygen-affine components of the alloy. These are then present as small crystallization nuclei and can thus lead to small oxide inclusions with grains which can be recognized as a peak in the micrograph at 1000 × magnification or in an X-ray diffractometry examination. Similar effects can also be caused by further or other impurities of the starting materials as well as other elements, such as nitrogen.

The duration of the temperature treatment depends mainly on the volume of the component and should not take too long, as a rule, since each small crystal nucleus acts as a seed crystal and so crystals can grow, or so spreads the unwanted crystalline phase in the component. In experiments with zirconium-based alloys, it was possible to show that a temperature treatment in the temperature range according to the invention with a maximum duration of 400 seconds per 1 mm component cross-section gives particularly good results. The heating-up phase should also take place as quickly as possible since, in some cases, the undesired crystal growth already occurs 50 Kelvin below the transformation temperature.

In the following, further embodiments of the invention will be explained with reference to a schematically illustrated flow chart, without, however, limiting the invention.

In the flow chart, T is the working temperature, T _{T is} the transformation temperature of the amorphous metal alloy, and T _{K is} the crystallization temperature of the amorphous phase of the metal alloy.

From a metallic alloy whose composition is suitable for forming an amorphous phase or which already consists of the amorphous phase, an amorphous metallic powder is produced. This is followed by a powder fractionation in which too small and too large powder particles or powder particles, in particular by sieving and air classification, are removed. The powder can then be pressed either with or without temperature entry in a desired shape. When the powder is pressed into the mold without the introduction of temperature, a temperature treatment is subsequently carried out, which in the context of the present invention is referred to as sintering or which causes sintering. The temperature treatment during pressing or after pressing takes place for a maximum period of 900 seconds per 1 mm component cross-section at a temperature above the transformation temperature T _T and below the crystallization temperature T _{K of} the amorphous phase of the metallic alloy used.

Following are concrete embodiments in which inventive methods are described and in which an evaluation of the results obtained in this way.

Example 1:

An alloy of 70.5% by weight zirconium (Haines & Maassen Metallhandelsgesellschaft mbH Bonn, Zr-201-Zirkon Crystalbar), 0.2% by weight hafnium (Alpha Aesar GmbH & Co. KG Karlsruhe, Hafnium Crystal Bar milled chips 99.7% Item number 10204), 23 , 9% by weight of copper (Alpha Aesar GmbH & Co. KG Karlsruhe, Copper plate, Oxygen free, High Conductivity (OFCH) Article number 45210), 3.6% by weight of aluminum (Alpha Aesar GmbH & Co. KG Karlsruhe, Aluminum Ingot 99.999% Article number 10571) and Niobium (Alpha Aesar GmbH & Co. KG Karlsruhe, Niobium Film 99.97% Article Number 00238) was heated in an induction melting plant (VSG, inductively heated vacuum, melting and casting plant, Nürmont, Freiberg) under 800 mbar argon (argon 6.0, Linde AG, Pullach) melted and poured into a water-cooled copper mold. From the thus produced alloy was prepared by a method such as WO 99/30858 A1 is known, produced in a Nanoval Schmelzverdüsungs apparatus (Nanoval GmbH & Co. KG, Berlin) by atomizing the melt with argon, a fine powder.

By separation by means of air classification with a Condux fine-grader CFS (Netsch Feinmahltechnik GmbH Selb Germany), the fine grain is separated, so that less than 0.1% of the particles are smaller than 5 microns in size, that is at least 99.9% of the particles one Diameter or a dimension of 5 microns or more, and by sieving through a test sieve with 125 microns mesh size (Retsch GmbH, Haan Germany, Article No. 60.131.000125) are removed all powder particles that are larger than 125 microns. The powder thus produced is examined by means of X-ray diffractometry and has an amorphous content greater than 95%.

In each case 5.0 grams of this powder fraction thus obtained are in a laboratory press 54MP250D (mssiencetific Chromatographie-Handel GmbH, Berlin) with a compression tool (32 mm, P0764, mssiencetific chromatography trade GmbH, Berlin) and a pressing force of 15 tons. The compacts are then densified in a vacuum sintering (Gero high-temperature vacuum annealing LHTW 100-200 / 22, Neuhausen) at 410 ° C and a pressure of about 10 ^-5 mbar for 120 seconds. Subsequently, the compacted compacts are finally compacted by hot isostatic pressing under a pressure of 200 megapascal (200 MPa) under high-purity argon (Argon 6.0, Linde AG, Pullach) at a temperature of 400 ° C for 90 seconds.

Fifteen such manufactured components are examined by means of metallographic micrographs on the amorphous area fraction in the microstructure. This shows that on average 92% of the surfaces are amorphous.

Example 2:

An alloy of 70.5% by weight zirconium (Haines & Maassen Metallhandelsgesellschaft mbH Bonn, Zr-201-Zirkon Crystalbar), 0.2% by weight hafnium (Alpha Aesar GmbH & Co. KG Karlsruhe, Hafnium Crystal Bar milled chips 99.7% Item number 10204), 23 , 9% by weight of copper (Alpha Aesar GmbH & Co. KG Karlsruhe, Copper plate, Oxygen free, High Conductivity (OFCH) Article number 45210), 3.6% by weight of aluminum (Alpha Aesar GmbH & Co. KG Karlsruhe, Aluminum Ingot 99.999% Article number 10571) and Niobium (Alpha Aesar GmbH & Co. KG Karlsruhe, Niobium Film 99.97% Article Number 00238) was heated in an induction melting plant (VSG, inductively heated vacuum, melting and casting plant, Nürmont, Freiberg) under 800 mbar argon (argon 6.0, Linde AG, Pullach) melted and poured into a water-cooled copper mold. From the thus produced alloy was prepared by a method such as WO 99/30858 A1 is known, produced in a Nanoval Schmelzverdüsungs apparatus (Nanoval GmbH & Co. KG, Berlin) by atomizing the melt with argon, a fine powder.

The fine grain was separated by separation by means of air classification Condux-Feinstsichter CFS (Netsch-Feinmahltechnik GmbH Selb Germany), so that less than 0.1% of the particles are smaller than 5 microns in size and by sieving through a test sieve with 125 microns mesh size (Retsch GmbH , Haan Germany, article number 60.131.000125), all powder particles larger than 125 μm were away. The powder thus produced was examined by means of X-ray diffractometry and has an amorphous content greater than 95%.

Each 15.0 grams of this powder fraction thus obtained was sintered by hot pressing at a pressure of 200 megapascals (200 MPa) at a temperature of 400 ° C for 3 minutes.

Fifteen such components were examined by means of metallographic micrographs on the amorphous area fraction in the microstructure. It showed that on average 85% of the areas are amorphous.

Example 3:

An alloy of 70.6% by weight of zirconium (Haines & Maassen Metallhandelsgesellschaft mbH Bonn, Zr-201-Zirkon Crystalbar), 23.9% by weight of copper (Alpha Aesar GmbH & Co. KG Karlsruhe, Copperplate, Oxygen free, High Conductivity (OFCH) Article number 45210) , 3.7% by weight of aluminum (Alpha Aesar GmbH & Co. KG Karlsruhe, aluminum ingot 99.999% article number 10571) and 1.8% by weight of niobium (Alpha Aesar GmbH & Co. KG Karlsruhe, niobium film 99.97% article number 00238) was used in an induction melting plant (VSG, inductively heated vacuum, melting and casting plant, Nürmont, Freiberg) under 800 mbar argon (argon 6.0, Linde AG, Pullach) melted and poured into a water-cooled copper mold. From the thus produced alloy was prepared by a method such as WO 99/30858 A1 is known, produced in a Nanoval Schmelzverdüsungs apparatus (Nanoval GmbH & Co. KG, Berlin) by atomizing the melt with argon, a fine powder.

The fine grain was separated by separation by means of air classification Condux-Feinstsichter CFS (Netsch-Feinmahltechnik GmbH Selb Germany), so that less than 0.1% of the particles are smaller than 5 microns in size and by sieving through a test sieve with 125 microns mesh size (Retsch GmbH , Haan Germany, article number 60.131.000125), all powder particles larger than 125 μm were removed. The powder thus produced was examined by X-ray diffractometry and has an amorphous content greater than 95%.

Each 15.0 grams of this powder fraction thus obtained was sintered by pressing under a pressure of 200 megapascals (200 MPa) at a temperature of 400 ° C for 3 minutes.

Fifteen such components were examined by means of metallographic micrographs on the amorphous area fraction in the microstructure. It turned out that on average 87% of the areas are amorphous.

Example 4:

An alloy of 70.6% by weight of zirconium (Haines & Maassen Metallhandelsgesellschaft mbH Bonn, Zr-201-Zirkon Crystalbar), 23.9% by weight of copper (Alpha Aesar GmbH & Co. KG Karlsruhe, Copperplate, Oxygen free, High Conductivity (OFCH) Article number 45210) , 3.7% by weight of aluminum (Alpha Aesar GmbH & Co. KG Karlsruhe, aluminum ingot 99.999% article number 10571) and 1.8% by weight of niobium (Alpha Aesar GmbH & Co. KG Karlsruhe, niobium film 99.97% article number 00238) was used in an induction melting plant (VSG, inductively heated vacuum, melting and casting plant, Nürmont, Freiberg) under 800 mbar argon (argon 6.0, Linde AG, Pullach) melted and poured into a water-cooled copper mold. From the thus produced alloy was prepared by a method such as WO 99/30858 A1 is known, produced in a Nanoval Schmelzverdüsungs apparatus (Nanoval GmbH & Co. KG, Berlin) by atomizing the melt with argon, a fine powder.

The fine grain was separated by separation by means of air classification Condux-Feinstsichter CFS (Netsch-Feinmahltechnik GmbH Selb Germany), so that less than 0.1% of the particles are smaller than 5 microns in size and by sieving through a test sieve with 125 microns mesh size (Retsch GmbH , Haan Germany, article number 60.131.000125), all powder particles larger than 125 μm were removed. The powder thus produced was examined by means of X-ray diffractometry and has an amorphous content greater than 95%.

50 grams of this powder fraction thus obtained were compressed in a laboratory press 54MP250D (mssiencetific chromatography-Handel GmbH, Berlin) with a pressing tool (32 mm, P0764, mssiencetific Chromatography-Handel GmbH, Berlin) and the maximum pressing force of 25 tons and under high purity Argon (Argon 6.0, Linde AG, Pullach) sintered at a temperature of 410 ° C for 5 minutes.

The component produced in this way was examined by means of several metallographic micrographs for the amorphous area fraction in the microstructure. This shows that on average 90% of the surfaces are amorphous.

Test and test methods 1) Method for Determining Particle Size of Metal Alloy Powders:

The particle size of inorganic powders was determined by laser light scattering with a Mastersizer 2000 (Malvern Instruments Ltd., Great Britain).

2) Test Method for Density Determination:

To determine the density, a geometrically exact cuboid can be created by grinding the surfaces so that it can be precisely measured with a digital micrometer (PR1367, Mitutoyo Messgeräte Leonberg GmbH, Leonberg). Mathematically, the volume is determined and then the exact weight is determined on an analytical balance (XPE analytical balances from Mettler-Toledo GmbH). By forming the ratio of weighed weight and calculated volume, the density is obtained.

The theoretical density of an amorphous alloy corresponds to the density at the melting point.

3) Test method for the determination of the amorphous area fraction in the component:

For this purpose, fifteen metallographic sections are made on the basis of DIN EN ISO 1463 using a SiC film 1200 (Struers GmbH, Willich) and subsequent polishing steps with diamond polishing agents of 6 μm, 3 μm and 1 μm (Struers GmbH, Willich) and finally is polished with the chemo-mechanical oxide polishing suspensions OP-S (Struers GmbH, Willich). The ground surfaces thus produced are grown under a light microscope (Leica DM 4000 M, Leica DM 6000 M) at a magnification of 1000 to crystalline surface portions in the micrograph examined. In this case, an evaluation is carried out according to area percent crystalline content to total area of the cut.

The features of the invention disclosed in the foregoing description, as well as the claims, the flowchart and the embodiments can be essential both individually and in any combination for the realization of the invention in its various embodiments.

Claims (13)

1. Method for producing a component from an at least partially amorphous metal alloy, comprising the steps of:

   providing a powder of an at least partially amorphous metal alloy, wherein the powder consists of spherical powder particles, wherein the spherical powder particles have a rounded, at least approximately spherical form and a ratio of the longest cross section to the shortest cross section that is at most 2 to 1 and wherein the greatest cross section of the powder particles is taken as the diameter, and the powder particles have a diameter of less than 125 µm and wherein the powder comprises less than 1 percent by weight of particles with a diameter smaller than 5 µm or the powder is screened or treated by air classification, so that it comprises less than 1 weight percent of particles with a diameter smaller than 5 µm;

   pressing the powder into the desired shape of the component to be generated;

   compressing and sintering the powder by means of a thermal treatment of the powder during the pressing or after the pressing at a temperature that lies between the transformation temperature and the crystallization temperature of the amorphous phase of the metal alloy, wherein the duration of the thermal treatment is chosen such that after the thermal treatment the component is sintered and has an amorphous fraction of at least 85 percent.
2. Method according to Claim 1, characterized in that the thermal treatment takes place under a vacuum, wherein the powder is preferably compressed by a thermal treatment under a vacuum of at least 10^-3 mbar.
3. Method according to Claim 1 or 2, characterized in that the powder is compressed by hot-isostatic pressing or hot pressing.
4. Method according to one of the preceding claims, characterized in that
   the duration of the thermal treatment is selected such that the component has an amorphous fraction of at least 90 percent, preferably of more than 95 percent, particularly preferably of more than 98 percent.
5. Method according to one of the preceding claims, characterized in that
   a powder of an amorphous metal alloy with at least 50 percent by weight of zirconium is used.
6. Method according to one of the preceding claims, characterized in that
   a powder of an amorphous metal alloy comprising

   a) 58 to 77 weight percent zirconium;

   b) 0 to 3 weight percent hafnium;

   c) 20 to 30 weight percent copper;

   d) 2 to 6 weight percent aluminium; and

   e) 1 to 3 weight percent niobium

   is provided.
7. Method according to one of the preceding claims, characterized in that
   the spherical amorphous metal alloy powder is produced by melt spinning, preferably by melt spinning in a noble gas, in particular in argon, particularly preferably by melt spinning in a noble gas of a purity of 99.99%, 99.999% or a higher purity.
8. Method according to one of the preceding claims, characterized in that
   the thermal treatment of the powder takes place at a temperature (T) between the transformation temperature and a maximum temperature, wherein the maximum temperature lies above the transformation temperature (T_T) by 30% of the temperature difference between the transformation temperature (T_T) and the crystallization temperature (T_K) of the amorphous phase of the metal alloy, wherein the maximum temperature preferably lies above the transformation temperature (T_T) by 20% or 10% of the temperature difference between the transformation temperature (T_T) and the crystallization temperature (T_K) of the amorphous phase of the metal alloy.
9. Method according to one of the preceding claims, characterized in that
   the duration of the thermal treatment is selected in dependence on the geometrical shape, in particular the thickness, of the component to be produced, preferably in dependence on the greatest relevant diameter of the component to be produced.
10. Method according to one of the preceding claims, characterized in that
    the duration of the thermal treatment is in a time range of 3 seconds per millimetre of the thickness or of the greatest relevant diameter of the component to be produced to 900 seconds per millimetre of the thickness or of the greatest relevant diameter of the component to be produced, wherein the duration of the thermal treatment is preferably in a time range of 5 seconds per millimetre of the thickness or of the greatest relevant diameter of the component to be produced to 600 seconds per millimetre of the thickness or of the greatest relevant diameter of the component to be produced.
11. Method according to one of the preceding claims, characterized in that
    the powder particles are plastically deformed by the thermal treatment.
12. Component made of a pressed, sintered, spherical, amorphous metal alloy powder, wherein the component has an amorphous fraction of at least 85 percent and is produced by a method according to one of Claims 1 to 11.
13. Use of a component according to Claim 12 for producing a gear wheel, an abrasive wheel, a wear-resistant component, a housing, a watch casing, a part of a gearing or a semifinished product.