EP2606997A1 - Method for manufacturing a component by metal powder injection moulding - Google Patents

Abstract

Manufacturing an assembly part (1), comprises: injection molding of metal powder, which is mixed with a binder; producing the individual components of the assembly part as separately molded green body, assembling a brown body (9) into a two-part or multipart brown body and sintering; subjecting brown body part to be joined to pre-sintering process; assembling at least one pre-sintered brown body part and at least one additional brown body part into a two-part or multipart brown body; and subjecting the two-part or multipart brown body into main sintering process. Manufacturing an assembly part (1), comprises: injection molding of metal powder, which is mixed with a binder; producing the individual components of the assembly part as separately molded green body, releasing the brown body parts, assembling a brown body (9) into a two-part or multipart brown body and sintering in the assembled state, where a brown body part (6) undergoes a shrinkage in the sintering process; subjecting brown body part to be joined to pre-sintering process, in which it undergoes a first shrinkage; assembling at least one pre-sintered brown body part and at least one additional brown body part into a two-part or multipart brown body; and subjecting the two-part or multipart brown body into main sintering process, where at least one pre-sintered brown body part undergoes less shrinkage during the main sintering process than the additional brown body part, and at least one pre-sintered brown body part and at least one additional brown body part are firmly joined together. At least three brown body parts are assembled and are sintered together in a sintering process. At least one brown body part is a connection part which is assembled prior to the sintering process with at least two additional brown body parts, and which undergoes a higher or lower shrinkage compared with at least two additional brown body parts during the sintering process, where at least two additional brown body parts are connected to each other via the connecting part.

Description

The invention relates to a method for producing a component by metal powder injection molding of metal powder mixed with a binder, in which individual components of the component are produced as separately shaped green compact and then unbonded brown compact sections which are assembled into a two- or multi-part brown compact and sintered in an assembled state become. The method is suitable, for example, for producing thermally stressed engine components with a geometrically complex structure.

It is known to produce components of high geometric complexity from different metals such as stainless steels, case hardening and tempering steels, intermetallic phases, titanium based light metals and the like by metal injection molding (MIM) with full material utilization and no or only with little rework. In metal powder injection molding, a metal powder is first mixed with a binder of thermoplastics and waxes to form a flowable material that can be processed in an injection molding process (feedstock). From the molded part produced during injection molding, the green compact, the binder is then dissolved out or thermally expelled, so that a porous - called Bräunling - molding is available, which has the same dimensions as the green body. In a subsequent heat process, the browning is sintered slightly below the melting temperature of the respective metal in a sintering furnace, usually in a protective gas atmosphere or sometimes in a vacuum. After sintering, in which the browning shrinks to the desired finished dimensions, the final molded part is present. A rework is generally not required.

From the DE 103 31 397 A1 It is known geometrically complicated components for an aircraft gas turbine, here individual, each of two or more vanes and an inner shroud portion and an outer shroud portion existing segments of a vane ring to produce by metal powder injection molding. In this method, the inner and outer cover tape sections are each prefabricated separately as Bräunling and then pre-sintered without shrinkage. The presintered vane and shroud bristles are then assembled into a vane segment and fixed together in the assembled layer by clamps and then sintered. A required for the preparation of a solid connection between the individual components intimate contact at the contact surfaces is not guaranteed by the arrangement of brackets. Due to the freedom of movement during sintering, which is limited by the fixing by means of clamps, undesired deformations and cracks on the assembled guide blade segment can also occur.

The US 2007/0202000 A1 describes a method for joining two components produced by metal powder injection molding, in which the two components to be joined have a different shrinkage during sintering. The two components have form-fitting interlocking projections or recesses. During sintering, that component which encloses the projections of the other component exerts a pressure on these projections. The subsequent connection of the two components is primarily ensured by the projections.

The invention has for its object to provide further methods for metal powder injection molding of geometrically complex shaped, composed of separately prefabricated Bräunlingen components in which an intimate, firm connection is achieved during the sintering process between the joined Bräunlingen.

According to the invention, this object is achieved by a method having the features of patent claim 1 and a method having the features of patent claim 14. Embodiments of the invention are specified in the subclaims.

Thereafter, the invention provides that at least one of the Bräunlingsteilstücke to be joined undergoes a pre-sintering process in which it undergoes a first shrinkage. However, this first shrinkage is less than the maximum shrinkage that the Bräunlingsteilstück can experience by sintering. The at least one presintered and thus preshrunk Bräunlingsteilstück and at least one other Bräunlingsteilstück are then assembled into a two- or multi-part Bräunling. Subsequently, the two- or multi-part Braunling undergoes a main sintering process. Here, the at least one pre-sintered Bräunlingsteilstück undergoes less shrinkage than the at least one further Bräunlingsteilstück, whereby the at least one pre-sintered Bräunlingsteil and the at least one further Bräunlingsteilstück are firmly connected.

Thus, the non-pre-sintered brown compact section shrinks more than the pre-sintered brown compact section, thereby providing pressure to the surfaces to be joined. The stronger shrinking Bräunlingsteilstück is automatically pressed to the less shrinking Bräunlingsteilstück so that always a Nullspaltmaß and an intimate connection between the Bräunlingsteilstücken is guaranteed. In the metal injection molding process, complex components can be provided in high quality. The method is suitable, for example, for producing thermally stressed engine components with a geometrically complex structure.

In one embodiment of the invention, it is provided that a presintered Bräunlingsteilstück and another Bräunlingsteilstück be formed on joining surfaces of the Bräunlingsteilstücke to be connected, form-fitting interlocking fasteners are interconnected before the main sintering process. It can be provided that the Bräunlingteil vorzufinternde before passing through the pre-sintering process has dimensions such that it is not connectable to the other Bräunlingsteilstück, and shrinks in the pre-sintering process such that the two Bräunlingsteilstücke can now be connected via the interlocking fasteners. The Bräunlingsteil vorzufinternde is thus provided with a connecting element such that a fit with the other Bräunlingsteilstück is guaranteed only after pre-sintering. After assembly, the two components are then finished sintered, wherein the non-presintered component shrinks more than the pre-sintered component.

In this way, not rotationally symmetrically shaped Bräunlingsteilstücke without interfering tools in the sintering process firmly connected to each other and complicated shaped, non-rotationally symmetric components, such as formed with shrouds turbine blades, are manufactured by metal powder injection molding.

In the connection elements of the Bräunlingsteilstücke is according to an embodiment of the invention to form-fitting interlocking projections and Recesses. It is provided that the projections taper towards the main body of the Bräunlingsteilstücks and this example, dovetail-shaped or club-shaped. The recesses of the other Bräunlingsteilstücks have a matching complementary shape.

Two variants are conceivable. According to a first embodiment, the projections are formed on that Bräunlingsteilstück which is pre-sintered, and the recesses are formed on the further Bräunlingsteilstück. That is, in the main sintering process, the brown compact section having the recesses and enclosing the protrusions of the other brown compact section exerts pressure on these protrusions. The resulting connection of the two components is primarily ensured by the projections and is essentially limited to the region of the projections and recesses.

According to a second embodiment, the recesses are formed on that Bräunlingsteilstück which is pre-sintered, and the projections are formed on the further Bräunlingsteilstück. This embodiment causes, on sintering the composite tanning bristle, the tanning portion having recesses to the tanning portion having projections is attracted by its more shrinking projections, whereby the respective contact surfaces between the Bräunlingsteilstücken pressed together. In this case, the surfaces on which the Bräunlingsteilstücke are drawn together during sintering of the composite Bräunlings, be arranged substantially parallel to each other, which includes a common curvature.

In this embodiment, it is achieved that a high pressure and thus an intensive surface contact of the two Bräunlingsteilstücke is achieved not only in the region of the projections and recesses, but rather along the entire contact surfaces, along which the two Bräunlingsteilstücke abut each other. In this variant of the invention, during the sintering of the composite bronling, in other words, the brown compact sections are pressed together over a large area against contact surfaces which are formed adjacent to the projections and recesses on the brown compact sections.

The projections and recesses of the Bräunlingsteilstücke to be joined are brought into positive engagement, for example by longitudinal displacement or rotation of the Bräunlingsteilstücke to be joined before sintering.

In further embodiments, the projections are convexly curved and the recesses concavely curved, for example in the form of spherical or lobe-shaped projections and recesses.

A further embodiment of the invention provides that at least three Bräunlingsteilstücke are assembled and sintered together in the main sintering process. In this case, one of the Bräunlingsteilstücke represents a connecting part, which is composable before the main sintering process with two more of the Bräunlingsteilstücke. The connecting part has for this purpose two connecting elements, for example in the form of projections or recesses. It is now either pre-sintered as part of the Bräunlingsteilstück or the two further Bräunlingsteilges are pre-sintered. Subsequently, the two further Braunling sections are connected to each other by means of the Bräunlingsteilstücks formed as a connecting part for the main sintering process. In the main sintering process, both brown compact sections are intimately connected to the brown compact section serving as a connecting part, so that they are intimately connected to one another via the connecting part.

In this case, the connecting part can be designed, for example, as an insert part (so-called "insert") which essentially has the shape of two recesses which are formed in the brown compact sections to be connected. It can be provided that the connecting part in the main sintering process pulls the other two Bräunlingsteilges each other and thereby a large area a Nullspaltmaß between contact surfaces of the adjacent Bräunlingsteilstücke is achieved.

The inventive method can also be used with rotationally symmetrical components. In this case, it is provided in an embodiment variant that the composite brown compact comprises an inner brown compact section and an outer brown compact section surrounding this with or without connecting elements. Here, the outer Bräunlingsteilstück is not pre-sintered Bräunlingsteilstück. In the main sintering process, the outer brown compact section is pressed against the inner brown compact section.

It is provided in one embodiment that the at least one presintered Bräunlingsteilstück pre-sintering a volume shrinkage of at least 2% experiences. This ensures the creation of a sufficient pressure between the surfaces to be joined in the main sintering process.

An advantage of the method according to the invention is that due to the inventive concept of pre-sintering at least one of the Bräunlingsteilstücke a different shrinkage of Bräunlingsteilstücke is achieved during the main sintering process, even if the Bräunlingsteilstücke to be joined consist of the same material and have substantially identical shrinkage properties. Accordingly, according to one embodiment, the invention is realized with sections which consist of the same material, have the same binder shares and thus have substantially identical shrinkage properties. The use of different materials, which is associated with an additional cost along the process chain and thus increased component costs, is avoided.

Nevertheless, the invention can in principle also be realized with brown compact sections which have different shrinkage properties even without presintering of one of the brown compact sections in the sintering process. Thus, it may alternatively be provided that one or more of the Braunling sections, including the Bräunlingsteilzusszuszusternden, consist of different metal powders in the sense that the metal powder used on the nature and / or size of the metal powder particles, in the metal powder material and / or in terms of the binder used differ. Different metal powders in this sense are present in particular if the metal powder particles are of different types and / or sizes, but also if only the binder used is different or added to varying degrees to the metal powder particles used.

According to a second aspect of the invention, there is provided a method for producing components by metal powder injection molding, in which at least three brown compact sections are assembled and then sintered together in a sintering process. One of these Bräunlingsteilstücke is a connecting part, which is assembled before the sintering process with at least two further Braunlingsteilstücken. This formed as a connecting part Bräunlingsteilstück undergoes during the sintering process in comparison to the other Bräunlingsteilstücken higher or lower shrinkage, whereby the at least two further Bräunlingsteilstücke are firmly connected to each other via the connecting part.

It can be provided that the connecting part and the other Bräunlingsteilstücke consist of the same material and have substantially identical shrinkage properties. For this case, either the connecting part or the further Braunling sections undergo a pre-sintering process before the sintering process, by a pre-shrinkage takes place. However, the method of the second aspect of the invention is also applicable using a connecting part, which has other shrinkage properties due to its material composition than the Bräunlingsteilstücke to be joined together. For example, it differs in type and / or size of the metal powder particles and / or in the metal powder material and / or in the binder used by the other Braunling sections.

The connecting part is designed, for example, as an insert part, which has two projections which are arranged essentially completely in two corresponding recesses of the brown body sections to be connected to one another. If the insert has a greater shrinkage than the Bräunlingsteilstücke to be joined together, it draws during sintering the latter together, which experience a large area a pressure along their contiguous contact surfaces. If the insert has a lower shrinkage than the Bräunlingsteilstücke to be joined together, these Bräunlingsteilstücke exert pressure on the projections of the insert during sintering, the subsequent connection of the two components is primarily ensured by the projections.

Fig. 1

schematisch ein erstes Bräunlingsteilstück mit einem Vorsprung und ein zweites Bräunlingsteilstück mit einer Ausnehmung, wobei das mit einem Vorsprung versehene Bräunlingsteilstück in einem Vorsinterprozess eine erste Schwindung erfahren hat;

Fig. 2

schematisch ein erstes Bräunlingsteilstück mit einem Vorsprung und ein zweites Bräunlingsteilstück mit einer Ausnehmung, wobei das mit einer Aussparung versehene Bräunlingsteilstück bei einem Vorsinterprozess eine erste Schwindung erfahren hat;

Fig. 3

ein Ausführungsbeispiel eines erfindungsgemäß hergestellten Bauteils in Form einer mit einem Innen- und einem Außenband ausgebildeten Turbinenschaufel, die aus drei separat gefertigten Bräunlingsteilstücken zusammengesetzt ist;

Fig. 4

eine schematische Darstellung des Fügebereichs eines aus zwei Bräunlingsteilstücken zusammengesetzten Bräunlings, wobei der Zustand beim Hauptsinterprozess dargestellt ist; und

Fig. 5

schematisch ein Ausführungsbeispiel, bei dem ein erstes und ein zweites Bräunlingsteilstück durch ein drittes Bräunlingsteilstück, das als Einsatzteil ausgebildet ist und eine unterschiedliche Schwindung besitzt, miteinander verbunden werden.

The invention will be explained in more detail with reference to the figures of the drawing with reference to several embodiments. Show it:

Fig. 1

schematically a first Braunling section with a projection and a second Braunling section with a recess, wherein the provided with a projection Bräunlingsteilstück has undergone a first shrinkage in a pre-sintering process;

Fig. 2

schematically a first Braunling section with a projection and a second Bräunlingsteilstück with a recess, said provided with a recess Bräunlingsteilstück has undergone a first shrinkage in a pre-sintering process;

Fig. 3

an embodiment of a component according to the invention in the form of a formed with an inner and an outer belt turbine blade, which is composed of three separately manufactured Bräunlingsteilstücken;

Fig. 4

a schematic representation of the joining region of a Bräunlings composed of two Bräunlingsteilstücken, the state is shown in the main sintering process; and

Fig. 5

schematically an embodiment in which a first and a second Bräunlingsteilstück by a third Bräunlingsteilstück, which is designed as an insert part and has a different shrinkage, are interconnected.

The FIG. 1 schematically shows two Bräunlingsteilstücke 5, 6. The two Bräunlingsteilstücke are made of identical materials, so have the same shrinkage properties in a sintering process. To produce the Braunling sections 5, 6, separate green compacts are produced by metal powder injection molding of a metal powder mixed with a thermoplastic binder ("feedstock"). By melting out of the binder in an oven, the green bodies are then debinded, so that now existing from a porous material Bräunlingsteilstücke 5, 6 are available.

The one Braunling section 6 has on its outer surface a projection 7. The projection 7 is formed in the illustrated embodiment, but not necessarily dovetailed. Its side surfaces 75 taper in the direction of the main body of the Bräunlingsteilstücks 6.

The other Bräunlingsteilstück 5 has a recess 8, the shape of which corresponds to the shape of the projection 7 and, accordingly, also dovetail-shaped. The projection 7 and the recess 8 are form-fitting interlocking connecting elements of the two Bräunlingsteilges 5, 6 represents. In other embodiments, the form-fitting interlocking connecting elements can be provided in other ways, for example by concave and convex shapes.

The Bräunlingteilstücke 5, 6 interconnected via the interlocking connecting elements 7, 8 form a two-part Bräunling. 9

It is now envisaged that the one Braunling section 6 before a positive connection with the Bräunlingsteilstück 5 passes through a pre-sintering process in which its volume from a first, larger volume 61 to a second, smaller volume 62 shrinks. Accordingly, the outer dimensions of the projection 7 shrink from a larger outer dimension 71 to a smaller outer dimension 72. The shrinkage process is schematically represented by arrows. The size of the projection 7 and the recess 8 are adapted to each other so that only after passing through the pre-sintering process, the projection 7 can be introduced into the recess 8, while this was not possible before passing through the pre-sintering process. For interlocking connection the Bräunlingsteil 5, 6 are shifted longitudinally to each other, wherein the projection 7 in positive engagement with the recess 8 device.

After presintering of the brown compact section 6 and its connection with the non-pre-sintered brown compact section 5, the two brown compact sections 5, 6 undergo a main sintering process. Since the Bräunlingsteilstück 6 has already experienced a first shrinkage in the pre-sintering process, it experiences during the main sintering process less shrinkage than the other Bräunlingsteilstück 5. As a result, the Bräunlingsteil 5 and the Bräunlingsteil 6 are firmly connected. This connection is made such that the brown compact section 5, which shrinks more during the main sintering process, exerts pressure on the projection 7. The resulting connection of the two components 5, 6 is primarily ensured by the projections 7 and is limited by the cross-sectional area (i.e., the base area of the projections).

The FIG. 2 shows an alternative embodiment, which differs from the embodiment of FIG. 1 differs in that the Bräunlingsteilstück 5 having the recess 8, passes through a pre-sintering process and thereby shrinks from a larger volume 51 to a smaller volume 52. Accordingly, the surface within the recess also changes from a surface 81 to a surface 82. After presintering the brown compact section 5, the two brown compact sections 5, 6 are connected to one another in a form-fitting manner via their connecting elements 7, 8. This is followed by a main sintering process in which the two browning sections 5, 6 are sintered simultaneously.

In the embodiment of FIG. 2 learns the Bräunlingsteilstück 6 a greater shrinkage, since it has undergone no presintering. This results in that the two Bräunlingsteil 5, 6 are pulled together and pressed together, with an intimate connection along the entire contact surfaces 10, 11 of the two Bräunlingsteil 5, 6 is provided. Accordingly, a high pressure and an intensive surface contact of the two Braunling sections 5, 6 are achieved not only in the region of the projections 7 and recesses 8, but rather along the entire contact surfaces 10, 11, along which the two Bräunlingsteilstücke abut each other.

The FIG. 3 shows a possible embodiment of the in the Figures 1 and 2 illustrated technical teaching. It is shown a non-rotationally symmetrical engine component in the form of a turbine blade 1. The turbine blade 1 is composed of three separately produced by metal powder injection molding and then sintered in a sintering process and interconnected Bräunlingsteilstücken. The three sintered Bräunlingsteilstücke form an airfoil 2, an outer shroud 3 and an inner shroud 4 of the turbine blade. 1

To produce the non-rotationally symmetrical engine component 1, separate green compacts of the outer and inner shrouds and of the airfoils are produced by metal powder injection molding of a metal powder (feedstock) mixed with a thermoplastic binder. By melting out the binder in an oven, the green compacts are then debinded, so that now existing from a porous material Bräunlingsteilstücke for the blade and the inner and outer shrouds are available.

Like the in Fig. 4 shown joint between two separately manufactured outer and inner Bräunlingsteilstücken 5 and 6, are located on the contact surface 10 of a Bräunlingsteilstücks 5, the inner surface of the outer shroud 3 of the Fig. 3 corresponds to the contact surface 10 toward approximately dovetail-shaped tapered projections 7 and at the contact surface 11 of the other Bräunlingsteilstücks 6, the upper edge of the airfoil 2 of the Fig. 3 corresponds to about dovetail tapered recesses 8. In the same way is also another - to form the inner cover tape 4 of Fig. 3 provided - outside Bräunlingsteilstück (not shown) provided with such projections which engage in formed on the lower edge of the inner Bräunlingsteilstücks 6 recesses (not shown). Instead of Dovetail-shaped tapered projections may alternatively also be realized in another way to the contact surface 10 tapering projections.

The connecting elements in the form of projections 7 and recesses 8, which are produced in the metal powder injection molding process, interlock with one another in a form-locking manner in the assembled brown compact 9. The FIG. 4 shows the state after one of the two Bräunlingsteilstücke was pre-sintered and connected to the other Bräunlingsteilstück. Thus, in the considered embodiment, the Bräunlingsteilstück 6, which has the recesses 8, pre-sintered. This means that in the subsequent common sintering of the Bräunlingteilstücke 5, 6 positively connected by means of the recesses 8 and projections 7, the Bräunlingsteilstück 5 shrinks more. In this case, due to the fact that the Bräunlingsteiles 5 shrinks more in the main sintering process, and due to the tapered shape of the projections 7, the protrusions 7 zoom the Bräunlingsteilstück 6 to the Bräunlingsteilstück 5, wherein the respective contact surfaces 10, 11 are pressed together. In this case, a Nullspaltmaß between the contact surfaces 10, 11 is achieved. The corresponding force which acts on the Bräunlingsteilstück 6 and leads to a Andrückdruck between the two Bräunlingsteilstücken 5, 6 along the contact surfaces 10, 11, is in the Fig. 4 indicated by arrows F.

As a result of the sintering process, an engine component made of metal powder injection molding of geometrically complicated structure is provided.

The contact surfaces 10, 11, which are formed adjacent to the projections or recesses 7, 8, are formed in a configuration substantially parallel, which includes that they form curved surfaces in the same way. As a result, a large-scale intensive pressing process is ensured during sintering.

The FIG. 5 shows an embodiment in which three Braunling sections 5a, 5b and 12 are joined together in a sintering process. The Bräunlingsteilstück 12 is formed in the form of an insert having two circular or lobe-shaped projections 12a, 12b, which are arranged in corresponding recesses 8a, 8b of the Bräunlingsteilstücke 5a, 5b.

The insert 12 serves as a connecting part for connecting the two Bräunlingsteil 5a, 5b in a sintering process. It is provided that the insert 12 in comparison to the Bräunlingsteiles 5a, 5b in the sintering process a experiences higher or lower shrinkage. This can be achieved, on the one hand, by virtue of the insert part 12 having different shrinkage properties due to a different choice of material. For example, the type and / or size of the metal powder particles are different and / or a different binder or amount of binder is used. Because of these inherent different material properties, the brown compact section 12 serving as the insert undergoes a different shrinkage in the sintering process.

A different shrinkage of the insert part 12 may according to the embodiment of Figures 1 and 2 but also be achieved in that either the insert part 12 or the Bräunlingsteiles 5a, 5b experience a pre-sintering, which also leads to the fact that the insert 12 and the Bräunlingsteil 5a, 5b undergo shrinkage in the main sintering process in different ways.

In one exemplary embodiment, provision is made for the insert part 12 to experience greater shrinkage in the sintering process than the brown body sections 5a, 5b. This leads - according to the explanation of Figures 2 and 4 - In addition, the two Bräunlingsteiles 5a, 5b are not only firmly connected to each other via the insert 12, but while the insert 12 pulls the Bräunlingsteiles 5a, 5b together, so that they are pressed together along their contact surfaces 10, 11.

However, it is also possible that the insert 12 experiences a shrinkage in the sintering process, which is less than the shrinkage experienced by the Bräunlingsteil 5 a, 5 b. In this case, a connection between the respective Braunling sections 5a, 5b and the insert 12 substantially in the region of the projections 12a, 12b.

The exemplary embodiments described above were directed to the production of non-rotationally symmetrical components made of two or more tufts formed with connecting elements. However, the invention is not limited to such embodiments. Starting from the idea of suspending the Bräunlingsteilstücke to be joined by a pre-shrinkage of a section in a Vorsinterprozess and a different shrinkage in a main sintering process of a press, it is sufficient for rotationally symmetrical components without the mentioned connecting elements 7, 8, if the inner Bräunlingsteilstück comprehensive outside Bräunlingsteilstück has a greater shrinkage or shrinkage in the main sintering process, so that the separately manufactured, rotationally symmetrical Bräunlingsteilstücke are pressed firmly together during sintering.

Finally, it is also conceivable to use an additional, more shrinking Bräunling as a tool that comprises the Bräunlingsteilstücke to be connected and presses together during common sintering together.

The invention is not limited in its embodiment to the above-described embodiments, which are only to be understood as examples. For example, the shapes and dimensions of the recesses and recesses of the individual Bräunlingsteilstücke are merely exemplary understood. It can also be provided that Bräunlingsteilstücke to be joined together have a plurality of corresponding projections and recesses. Also in the FIG. 3 described embodiment of an engine component is to be understood as exemplary only. The invention can be realized in any components, in particular engine components, which consist of different, resulting from metal powder injection molding components, engine components can be made with geometrically complex structure.

Claims (15)

Process for the production of a component (1) by metal powder injection molding of metal powder mixed with a binder, in which individual components of the component are produced as separately shaped green compacted and then unbonded brown compacted sections (5, 6) forming a two- or multi-part browning (9 ) are sintered and sintered in the assembled state, wherein the Bräunlingsteilstücke (5, 6) experience a shrinkage in the sintering process,
characterized, - that at least one of the Bräunlingsteilstücke (5, 6) to be connected undergoes a pre-sintering process, in which it undergoes a first shrinkage, - The at least one pre-sintered Bräunlingsteilstück (5, 6) and at least one further Bräunlingsteilstück (6, 5) to a two- or multi-part Bräunling (9) are assembled, and - The two- or multi-part Bräunling (9) then undergoes a main sintering process, wherein during the main sintering process, the at least one pre-sintered Bräunlingsteilstück (5, 6) experiences less shrinkage than the at least one further Bräunlingsteilstück (6, 5), whereby the at least one pre-sintered Bräunlingsteilstück (5, 6) and the at least one further Bräunlingsteilstück (6, 5) are firmly connected. A method according to claim 1, characterized in that a pre-sintered Bräunlingsteilstück (5, 6) and another Bräunlingsteilstück (6, 5) on joining surfaces of the Bräunlingsteilstücke to be connected (5, 6) formed, positively interlocking connecting elements (7, 8) before the Main inter-process. A method according to claim 2, characterized in that the Bräunlingsteil vorzusinternde (5, 6) before passing through the Vorsinterprozesses dimensions such that it is not connectable to the further Bräunlingsteilstück (6, 5), and shrinks in the pre-sintering process such that the two Bräunlingsteilstücke (5, 6) via the now interlocking connecting elements (7, 8) can be connected. A method according to claim 2 or 3, characterized in that the connecting elements (7, 8) of the Bräunlingsteilstücke (5, 6) in the form of positively interlocking projections (7) and recesses (8) are provided, wherein the projections (7) for Contact surface (10, 11) taper between the Bräunlingsteilstücken (5, 6) out, for example, dovetail-shaped or club-shaped, and the recesses (8) have a mating complementary shape. A method according to claim 4, characterized in that the projections (7) are formed on the Bräunlingsteilstück (6), which is pre-sintered, and the recesses (8) on the further Bräunlingsteilstück (5) or that the recesses (8) on the Bräunlingsteilstück (5) are formed, which is pre-sintered, and the projections (7) on the further Bräunlingsteilstück (6). Method according to one of claims 4 to 5, characterized in that the projections (7) are convexly curved and the recesses (8) are concave. Method according to one of the preceding claims, characterized in that at least three Bräunlingsteilstücke (5a, 5b, 12) are assembled and sintered together in the main sintering process, wherein one of the Bräunlingsteilstücke a connecting part (12) with two connecting elements (12a, 12b) represents such that it can be assembled before the main sintering process with two further of the brown compact sections (5a, 5b), wherein - either the connecting part (12) formed Bräunlingsteilstück is presintered, or - The two further Braunling sections (5a, 5b) are pre-sintered, and then the two further Braunling sections (5a, 5b) by means of the formed as a connecting part (12) Bräunlingsteilstücks for the main sintering process. A method according to claim 7, characterized in that the connecting part (12) formed Bräunlingsteilstück as connecting elements two projections (12a, 12b). A method according to claim 7 or 8, characterized in that in the main sintering process, the Bräunlingsteilstück formed as a connecting part (12) pulls the two other Bräunlingsteilstücke (5a, 5b) to each other. Method according to one of the preceding claims, characterized in that in rotationally symmetrical components of the composite Bräunling an inner Bräunlingsteilstück and enclosing this outer Bräunlingsteilstück with or without fasteners, wherein the outer Bräunlingsteilstück is not pre-sintered Bräunlingsteilstück and the main sintering process of the composite Bräunlings to the inner Bräunlingsteilstück is pressed. Method according to one of the preceding claims, characterized in that the at least one pre-sintered Bräunlingsteilstück (5, 6) and the further Bräunlingsteilstücke (6, 5) consist of the same material and have substantially identical shrinkage properties. Method according to one of the preceding claims, characterized in that the at least one pre-sintered Bräunlingsteilstück (5, 6) undergoes pre-sintering volume shrinkage of at least 2%. Method of manufacturing a component (1) by metal powder injection molding of metal powder mixed with a binder, in which individual components of the component are produced as separately shaped green compact and then unbonded brown compact sections (5a, 5b, 12) which are assembled into a multi-part brown compact and integrated in sintered composite state, wherein the Bräunlingsteilstücke (5a, 5b, 12) experience a shrinkage in the sintering process,
characterized
that at least three Bräunlingsteilstücke (5a, 5b, 12) are assembled and then sintered together in a sintering process, wherein one of the Bräunlingsteilstücke is a connecting part (12), which is assembled before the sintering process with at least two further Bräunlingsteilstücken (5a, 5b), and that undergoes a higher or lower shrinkage compared to the at least two further Braunling sections (5a, 5b) during the sintering process, whereby the at least two further Bräunlingsteilstücke (5a, 5b) are firmly connected to each other via the connecting part (12). A method according to claim 13, characterized in that connecting part (12) and the other Bräunlingsteilstücke (5a, 5b) consist of the same material and have substantially identical shrinkage properties, wherein the connecting part (12) or the further Bräunlingsteilstücke (5a, 5b) before The sintering process has undergone a pre-sintering process in which it / they have experienced a Vorschwindung / have. A method according to claim 13 or 14, characterized in that the connecting part (12) by differences in the type and / or size of the metal powder particles and / or in the metal powder material and / or the binder used in comparison to the other Bräunlingsteilstücken (5a, 5b) has different shrinkage.

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