DE2017260A1 - Device for spinning low viscosity melts - Google Patents

Description

PATENT LAWYERS ⁴ '

β CHICKEN 2. HlLBLESTRASaE

Dr. Berg Dipl.-Ing. Stopf, SMOndnn 2, Hilblettrofl «30

Your sign Untar Ztfdiwi date

Attorney's file 19 419 ■ 10 »ÄPfH 1970

MONSANTO COMPANY St. Louis, Missouri / USA

Device for spinning low viscosity melts.

The invention "relates to melt spinning high temperature with a device to prevent a crucible smell and the build-up of low

11-52-0052 .- - 2 -

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hit 'near or inside extrusion nozzle. The . In particular, the present invention relates to a thermally anisotropic plate that can be used in conjunction with a Heating device is used to avoid the creation of significant heat gradients in a bottom of a crucible provided with an extrusion nozzle.

It is known that in melt spinning, especially in the high temperatures associated with some melt spinning processes occur, heat gradient along the bottom of the bar containing the melt due to the heat loss emerge down through the soil, being the largest Heat loss occurs in the vicinity of the spray nozzle or the spray opening. At low temperatures this is small Thermal gradient that stresses in the bottom of the crucible usually small, since the materials used to make crucibles have physical properties that make the crucible Withstands stress.

However, when the temperatures required to produce a melt rise, considerable stresses occur on, which can be determined first at the connection between the wall and the bottom of the crucible are. Since certain materials are used to make Crucibles are expensive, and other materials are made by the melt can be chemically attacked,

009841/1385

BATHROOM ORiGiNAL 3 -

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Economic and practical considerations limit the materials used to those which can break due to thermal stress. The problem of breakage has been reduced in part by the introduction of two-part crucibles that allow the wall and bottom plate of the crucible to expand freely found that a two-part crucible "works satisfactorily for melts such as glass. If, however, a melt with a high temperature of over 1000 ^° C., such as a steel melt, is used in a melt spinning process, slight fractures occur in the bottom plate, even of two-part crucibles due to the strong heat gradient within the crucible bottom and / or the support frame. The occurrence of thermally induced fracture is particularly noticeable when refractory materials such as ceramics are used for the manufacture of crucibles. As stated above, the heat gradient that arises within the crucible base is based on the loss of heat through the base, particularly in the vicinity of the extrusion opening or nozzle. The heat gradient within the support frame is created in a similar way by the heat loss downwards. Since the extrusion opening radiates heat slightly downwards and is often cooler than the surrounding melt, deposits occur near or within the opening, which clogs the nozzle. This is especially "then the pail,

009841/1386 ⁴ "

BATH ORIGINAL

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when the reaction equilibrium between the melt and the crucible material depends on the temperature of the melt. ". ■ --...--- .. ', .. ..-.

In particular, the invention provides a device which the creation of "considerable heat gradients in the bottom of a Crucible prevented.

The invention also provides a device with which the temperature of the extrusion opening is maintained at values can be, "where a precipitate inside or near the nozzle is kept extremely small *

According to one embodiment of the present invention a melting pot provided, the bottom of which in, physical Contact with a thermal; anisotropic plate. ' The plane of the high thermal conductivity of the plate is referred to below as the "a-b" plane and is arranged in this way » that they are essentially parallel to the lower surface of the floor is. See an opening in the ani so tr opi · "plate., Whose Axis is essentially perpendicular to the ar-b plane, is im essentially coaxial with the extrusion opening of the crucible .floor aligned. A receptacle surrounds the crucible and rests on the anisotropic plate Device for heating the receiving body and the outer

^: "--.-. '"■;". ■ ;. - 5 ->: --_ .0 098 * 1/1386 BAD ORIG ₁ NAL

ren area of the anisotropic plate is provided. The thermal characteristics of the anisotropic plate, i.e. the almost constant temperature along the a-b plane and the direction of travel of the heat along the bottom of the crucible, ■ make sure that the heat gradient in the base plate is extremely small «Since the heat easily reaches the places is directed on the upper surface of the anisotropic plate, which is located near the spray opening, the extrusion opening can be kept at an optimum temperature at which precipitation is prevented.

To avoid possible breakage due to thermal expansion of the To prevent the crucible bottom and the resistance exerted by the crucible wall on the crucible bottom can be a two-part process Crucible, which has a separate bottom and a separate wall, together with. the anisotropic plate is used will. The bottom plate and the wall of the crucible can expand independently of one another. A Leakage between these parts is prevented by the fact that the; Surfaces of the crucible wall in contact with one another and overlap the crucible bottom and that a melt is used, which the walls of the crucible not wetted.

The novel characterizing features of the present invention are set out in the appended claims.

009841/1385 " ⁶ "

The invention with its further objects and advantages will be explained in more detail with reference to the drawings.

Fig. 1 shows a vertical cross section through a Device for spinning a melt lower Viscosity according to an embodiment of the present invention.

Fig. 2 shows a vertical cross section through a; Device for spinning a melt lower Viscosity according to another embodiment of the present invention. .

Fig. 3 shows a top view of the line of force concentration

Fig. 4 shows a vertical cross section through a; Device for spinning a melt of lower viscpy sity according to a further embodiment of the

_v lying invention. ^ - ■■. "," ■ ";.

Fig. 1 shows a vertical section through a device for spinning a low viscosity melt. In the device, a stand 10 carries a thermally anisotropic one Plate 11 »which in turn carries a receiving body 12 and a crucible arrangement 13. The Crucible

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The crucible arrangement 13 has a base plate 14, a cover plate 15 and a wall part 16. The bottom plate 14 and the cover plate Ig are essentially parallel to?? anisotropic plate 11. The anisotropic plate 11, the receiving body 12 and the crucible assembly 13 have in the present case a cylindrical shape, the crucible arrangement 13 being coaxial with the Receiving body 12 is surrounded. It should be noted, however, that various configurations can be made as required and desired sfοrmeη can be used.

The use of induction coils, such as a coil 17 for heating a crucible and a melt are "known. The induction coil 17, the serves to supply the energy required to melt the spin charge in the crucible arrangement 13, follows a helical line around the anisotropic plate 11 and the receiving body 12. The alternating current source for generating a suitable electromagnetic field is not shown. After being switched on, the coil 17 induces a secondary current in the receiving body 12 and in the peripheral area the anisotropic plate 11. The heat generated by the induced alternating current is' from the receiving body 12 to Crucible assembly 13 blasted and / or directed, whereby the charge is melted.

009841/1385

As noted above, the one-piece sea crucible constructions are sensitive to breakage when exposed to heat, especially when large. . SchmelZtiggelkonstruktio- "- new concerns, which operate at temperatures that are required for the frictionless melt spinning Small crucibles have a greater resistance to breakage due to the heat, because it is easy to maintain uniform temperatures in them little: but melting pot constructions-are. Not expedient for various reasons. Their size, for example, "unreasonably reduces the number of spinnerets that can be provided. In addition, small one-piece crucibles are undesirably sensitive to breakage when exposed to heat, even if their sensitivity to breakage is lower, as explained above. . . >, _: . ■■ "'-."

One-piece crucible assemblies also have the further disadvantage that a thermal structural defect in any part leads to the complete loss of the assembly. The assembled assemblies are particularly sensitive in the area of the connection between the crucible bottom and the crucible wall. The crucible bottom and the crucible wall prevent each other from moving freely expansion and _{contraction;:} SSO that strong stresses arise in this area, perform the häufig.zu break ■ ^";...

- - 9 9 841 / 138S -. "" '': / ". '.

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ils has therefore proven to be advantageous to have a. Provide two-piece crucibles for melt spinning when non-wetting melts, as in Pig. I, spun should be. Like in Pig. 1, a wall part 16 is arranged on a floor or a base, which is shown in FIG present Pail has a bottom plate 14 and a cover plate. Since the wall part 16 and the base that the Base plate 14 and the cover plate 15 comprise, expand or contract freely, the thermal stress is not "• present at the connection between the wall and the Bottom is found in one-piece crucibles. Friction-free melts, by which melts are meant, the one Have a viscosity of at most 1 poise, tend to penetrate between the wall part 16 and the base. Around avoiding the need for expensive and large brackets it has proven to be useful to have overlapping surfaces lying on top of one another for the wall part 16 and the base. The weight of the wall part 16 is sufficient to achieve a perfect seal to achieve the contact surface. However, brackets can be used as desired.

The space formed by the crucible arrangement 13 contains a low-viscosity melt 18. The cover plate 15 has

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the task, the · bottom plate 14 and a nozzle insert piece to be held securely, provided that di'e ^ sy is used as described below. The cover plate 15 also has the Task to help prevent leakage between the wall part 16 and the bottom plate 14. Using the phrase "soil" of the crucible therefore becomes the entire bottom of the crucible assembly in all the "cases in which the Floor is a single part or a plurality of parts .; Even if the crucible 13 is shown and described as a two-part crucible, it is self-evident. of course that this refers to the fact that the wall and the floor are separate parts. Crucibles can also be made that have a variety of parts and yet are two-part crucibles according to the definition above. ~:

The bottom plate 14 has an opening 19, which is a separate Insert part, which forms the spinneret, receive or itself can be the spinneret. The size of the extrusions; - / or spinneret is primarily determined by the diameter of the desired thread. As shown in Fig. 1, the opening 19 is substantially coaxially aligned with the conical opening 20 in the anisotropic plate 11, which in turn is aligned with the chamber 21 in the stator 10 in Connection. Those from the crucible assembly 13

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Melt pressed out .18 flows unhindered through the opening 2Q into the chamber 21. lus G-rüiideii. For the sake of simplicity, the bottom plate 14 is shown with only a single opening 19, although it will be understood that a; ^; Floor can be with a plurality of openings in any arrangement provided when a ^{multiplicity:} number clay EAE wants the extruding or spinning. The word '' opening "denotes in the following very generally a nozzle or an opening which can receive a nozzle insert. The word" passage "in the following description means the passage through the anisotropic plate 11.; ■ _" - , '.; . · .. .-

It is; desirable to use ceramic materials for the iCorßtruktion of crucibles, if low viscosity. Materials such as copper and ₃ iron are spun. Such ceramic materials can be, for example, beryllium clay or zirconium clay. These materials are typical refractories mil; relatively low. lower thermal conductivities, high moduli and thermal expansion coefficients and low tensile strengths. If -hence ceramic material Lieh are not uniformly heated, they are subjected · by the thermal stress breakage when spinning a .dünnflüssigen metal under high temperature, for example in the spinning of copper or steel ₈ is ee

-12

usually extremely useful, induction heating, such as in Pig. 1, to be used to achieve temperatures which are sufficiently high to achieve a melt are. For example, if that's the size of the crucible load-bearing part has a significant heat gradient, the uneven heat distribution along the lower surface of the crucible soil often leads to a thermal break, *

It has been found to be extremely beneficial. to use physical properties of thermally anisotropic materials to solve the problem identified above. Examples of thermally anisotropic materials are pyrolytic boron nitride and. pyrolytic graphite * With pyrolytic graphite 'the thermal conductivity is in the. Direction of a plane by a few orders of magnitude larger than in a direction perpendicular to this plane. The unique thermal property of this material is "probably caused by the unusually high degree of preferential orientation of the crystallites". The crystallites tend to align their ground plane parallel in one direction. The high thermal conductivity lies in this direction (from level) .- - _: '. ο ; _ - ~ ~ ^:

By a plate ^: -11 made of thermally anisotropic material, such as pyroly1; ischem graphite, which is used in the

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_ 20172ΙΘ

Sold by Pyrogenics Inc. of Woodside, New York, is available, the heat gradient caused by heat loss through the nozzle opening can be reduced significantly arises in the base plate 14, whereby a thermal shock is avoided. The lower surface of the base plate is arranged essentially parallel to the a-b plane of the anisotropic plate 11. Since the induction coil 17 with the peripheral areas of the janisotropic near the turns Plate 11 cooperates is in the anisotropic Plate 11 induces heat which flows along the a-b plane to the passage 20, as indicated by the arrows 22 displayed. The temperature is almost constant along the a-b plane, which means that the heat is evenly distributed over the bottom plate 14 is reached at its lower surface. -The surface of the crucible bottom through the melt 18 too is heated evenly, the formation of considerable- " lent temperature gradients excluded, whereby a thermal break in the bottom of the crucible is avoided. ·

The lower surface of the bottom plate 14 near the opening 19 acts as a radiation body and radiates heat through the passage 20, which results in a considerable loss of heat caused, which leads to a lower temperature in the opening 19 and in the immediately surrounding melt than prevails in the rest of the melt. It arise

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therefore frequent precipitation or growth in the vicinity or within the opening 19, which causes a blockage. This problem increases particularly in significant proportions when the melt used and the soil _\: denplatte. are in chemical equilibrium and the equilibrium is temperature dependent. It is also preferred that the nozzle orifice be at least as hot as the melt in order to facilitate flow (low viscosity) and the rapid formation of a stabilizing film. When spinning a low-viscosity melt, it is important that the jet of free-flowing melt reacts quickly with a stabilizing gas in order to form a film to prevent surface expansion. The speed of the reaction usually increases with an increased temperature of the flowing melt. V ^Λ ν "·:.% ■.

ids is therefore desirable that the temperature of the anisotropic Plate 11 in the immediate vicinity of opening 19 is kept to a minimum, which prevents precipitation effectively prevent. As can easily be seen from "FIG are those closest to the opening 19 Points in the anisotropic plate 11 in the surface the plate; Il in the area of · passage 20,: Because of the anisotropic Eigengohaften of the plate 11 results, the Heat that is "easily conducted in the direction of the a-b plane,

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009841 / 138S

a temperature in the region of the passage 20 which is essentially the same as the temperature in the peripheral region the plate 11.

However, it can sometimes also be advantageous that the plate 11 induced in the circumference s-area of the anisotropic plate 11 Increase the amount of heat in order to further increase the temperature at the opening. Just an increased energy supply to the induction coil only serves to increase the temperature of the melt. However, this can be uncomfortable in that als.a certain material chosen for a melt has an increasing tendency to "with increasing temperatures to react with the crucible. As the temperature of the entire spinning device by this procedure • is increased if a single induction coil, for heating the receiving body and the anisotropic plate is used, the temperature difference between the nozzle opening is not canceled, so that the possibility increases that reaction products are deposited in the opening.

It has been found to be advantageous to keep the distance between the turns of the induction coil in the immediate vicinity of the 'an' isotropic plate narrower., i.e. to reduce the coil width, which increases the density of the electromagnetic

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Lines of force increased - which increase the circumference of the anisotropic Cut plate. This in turn increases the temperature the area in the vicinity of the plate passage, which, as previously mentioned, the points on the plate de-. . that is closest to the nozzle opening of the crucible lie. - "" - .. '., "". ;

In FIG. 1, the density of the turns 17 in the vicinity of the anisotropic plate 11 can be observed. The space between the turns can be changed for the desired purposes and, for example, in the case of a steel melt, 1.6 mm in the vicinity of the anisotropic plate 11 and 3.2 mm in the vicinity of the receiving body 12 / applied alternating current is selected, inter alia, so that it is matched to the dimensions of the objects to be heated. -The frequency can -; '. for example 10 KHz. ' - '■' _ ■■ - ■ -

Although it is advantageous that the anisotropic plate in physical contact with the bottom of the crucible it may be desirable under certain circumstances that the anisotropic plate is not in physical contact with the bottom of the crucible. For example, it is advantageous to use the reaction or stabilizing gas to prevent, immediately with the melt too

- If

react when it leaves the nozzle. In this case it may be necessary ^{to separate the part with the 1} spinning orifice from the anisotropic plate, as in Pig. 2 and is explained below. In the device shown, the melt is divided into several containers for better temperature control. The lower container, which contains a smaller amount of melt, can more easily be kept at a certain temperature, which is usually higher than the melt temperature of the upper container. Such a temperature difference between the containers is desirable in order to continue to prevent precipitation in the spinning orifice. In this arrangement, the stator 30 carries two thermally anisotropic plates 31 and 32. The stator 30, which is thermally insulated by the plates 13 and 32, can be made of stainless steel and the melt leaving the lower container 34 is carried by the anisotropic plate 32. The partition 33 in turn supports the bottom 35 of the crucible 34, ie the lower container, and in this way separates the anisotropic plate 32 from the bottom 35.

The stand 30, the anisotropic plates 31 and 32 and the partition 33 form a conical chamber 37 »die

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communicates at its upper end with the opening 3 & in the crucible, 34. A plate 38, which can consist of ordinary graphite * in order to ensure suitable thermal expansion, is used to hold the separating part 3, 3 in position and to hold the vertical wall part 39 of the crucible 34 and the receiving body 40 securely. A bottom 42 and a wall part 43 form the upper container 41.

As stated above '; serve the ani so tropical places 31 and 32 in addition, the stand 30 against the in.der spinning device occurring high temperatures too; isolate. It is hence from Torteil, “the heat flow to the upper area or the; upper portion of the anisotropic plate 32 to restrict. It. is therefore desirable to control heat flow only on the; upper surface of the anisotropic plate 32 to limit., since any heat flow in areas below this area does not serve any useful purpose. Furthermore it is advantageous to - increase the density of the lines of force su, which are the peripheral areas of the anisotropic plate 32 cut to. suitable heating of the orifice to accelerate. The concentration of the lines of force in proportion large areas of an object to be heated can accordingly be achieved by reducing the curl s from st aiides of the coil can be achieved, as in FIG. 1 shown. However, the minimum tangle distance is There are limits. That means ^ that the diameter of the

009841 / ^; t3: tS

Induction coil independent of the change in the distance between the windings is usually constant, and is a factor when further decreasing the pitch of the turns is required to induce heat in a relatively narrow area of the anisotropic plate. In particular, water-cooled coils represent a limitation, since a certain water flow rate for a suitable Cooling is needed. The water flow rate essentially determines the inner diameter of the coils, the is at least required.

The induction coil 44, which the receiving body 40 helically . Surrounds is used as an element in a line of force concentrator 45j for concentrating the lines of force in the upper peripheral portion of the anisotropic plate 32 is used. The line of force concentrator 45 has a multiplicity of Windings of the coil 44 in connection with a line part 46 in. In the manner of a washer, which in substantially surrounds the upper peripheral region of the anisotropic plate 32.

The Inner Winding. 47 is advantageous with its entire Length attached to the line part 46 and is in electrical contact with it. The line part 46 serves as Warehouse "and is even served by the water-cooled induction

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coil 44 cooled. The line part 46 is therefore advantageously made of a material such as copper, which / ches not just an electrical conductor, but also a is a good conductor of heat. As can be seen from FIG. 2, -.- is the Winding 47 on the line part 46 / attached, while the outer turns 48 and 49 lie slightly above the lead portion 46 to facilitate electrical insulation, although other means of insulation may be used as desired can. The inner turn47 can, however, also be similar Way over the line part 46, but in Yerbigung with him stand. ; ''. - ■ '■' '■. ·

Pig. 3 sets up a top view; the line of force concentrator -45 shows the spinning arrangement and shows a gap in the line part 46 .. The inner turn 47 extends see along the circumference of the line part 46 of the one. Side of the gap 50 to the other side. When the coil 44 is fed, the outer turns 48 and 49 are with the Line part 46 in connection with the flow of forces around the Winding 47 then rises. The concentration of the lines of force therefore increases in the "effort .. of the upper circumferential area the anisotropic sheet 32 on «" The slit-50 has the task of to avoid a short circuit of the inner turn: .47.

21 -

The line of force concentrator 45 has two advantages. First As mentioned above, it is possible to concentrate the heat generating lines of force on small areas. Second only a nominal increase in the longitudinal distance is required. Although Mg. 2 and 3 are only three laterally arranged, show helical turns of the coil 44 along the line part 46, it goes without saying that the number used increases or decreases as desired can be. Although it is appropriate, the heat absorbing body 40 and the peripheral area of the anisotropic plate 32 to heat with a coil and the like, this is not absolutely necessary. For example, at the one in Pig. 2, the coil 44 and the concentrator 45 by two separate energy inputs. be fed.

To continue to ensure, that the heat profile of the anisotropic Plate 32 is only continuously present in the upper areas, one or more grooves, like the annular groove 51, are used to transfer the heat. The annular groove 51, which runs essentially coaxially to the longitudinal axis of the conical chamber 37, is cut into die.anisotropische Platte 32 essentially perpendicular to the a-b plane. That way will the heat transfer in the lower areas of the-aniso-

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interrupted tropical plate 32. The arrows 52 indicate the continuous heat profile ″ above the annular groove 51.

The heat generated in the anisotropic plate 32 by the line of force concentrator 45 is conducted along the ab plane in the area in the mowing area of the upper surface of the anisotropic plate 32. When the heat reaches the boundary layer between the anisotropic plate 32 and the separating part 33, it is passed through the separating part 33 to the crucible bottom 35 and directly to the opening 36. It should be noted here that the non-anisotropic part 33 conducts heat equally in all directions. In this way, the temperature above the bottom 35 J- ^{ra is kept} substantially constant, and the temperature at the opening 36 can be at a value. which is very favorable for spinning.

As you can see, is the anisötropische plate 32, although it is not liegelboden in physical Berührungmitdem in Wärmeleitberührung with the bottom 35 "As part of this specification, the term" Wärmeleitberührung ¹¹ either eiiie contact between two Segenstän- • referred to, which physically touching each other, or touching another object on both sides, which conducts the heat between the two objects. '■■ _] ■ - "

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The separating part 33 therefore serves as a heat conductor between the anisotropic plate 32 and the bottom 35. The separating part is preferably made of a material such as "for example graphite", which has good thermal conductivity Has. However, when a high temperature melt such as a steel melt is used, it becomes very close because of the free-flowing melt be more appropriate for the production of the separating part 33 materials such as beryl alumina use.

In Pig. In the embodiment shown in FIG. 2, it may be expedient or necessary to reduce the direct contact between the melt and the stabilizing gas when the melt flows into the spinning chamber. Due to the active nature of certain stabilizing _{gases used in the spinning of selected s} low viscosity melts, an uncomfortable situation arises when the stabilizing gas reacts due to the presence of a heated object such as the partition and / or the walls of the chamber . It is therefore · important that the. To keep the temperature of the chamber walls, in particular the area in contact with the separating part 33, at a value which excludes noteworthy and undesirable reactions of the stabilizing gas.

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FIG. 4 shows another embodiment of the invention shown, with which the above condition can be easily met can achieve. As can be seen in this figure, .bears, a stand 60 two thermally anisotropic plates 61 and 62. The anisotropic plate 62 has a cylindrical_ Shape and has a diminished in its lower part Diameter on. The upper or protruding ..Part 63 of the anisotropic Plate 62 stands sideways. over the lower part. The stand 60 and the anisotropic plates and 62 form a chamber 64 into which the low-viscosity melt flows. The a-b planes of the anisotropic plates 61 and 62 extend substantially perpendicular to the longitudinal axis of the spinning device. ,, They the. Stan-, isolate the 60 against the spinning temperatures. The Stan-. . the 60 can therefore be made from a material such as stainless steel made; will. , ■.

The anisotropic plate 62 has a cylindrical- = gen passage or a hole on * the one in the middle of its upper area, and has a depth that is in the. substantially corresponds to the thickness of the lateral projection 33. That formed by the "'anisotropic plate 62 upper end of the chamber 64 is in communication with the bore. A part 65 with a spray opening 66 is in Drilling the anisotropic plate 62 using a

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0 0984t /

anisotropic centering ring 67 centered. The fat of the part 65, the ring 67 and the depth of the bore of the anisotropic plate 62 were for the sake of lighter description greatly exaggerated. The ring 67 is essentially supported by the anisotropic plate 62 surround and lies with its a-b plane parallel to the a-b plane of the anisotropic plate 62. The ring 67 can therefore can be viewed as a projection or continuation of the anisotropic plate 62.

A partition 68 is attached to the anisotropic plate 62 at the top of the chamber 64. The separator 68 has the task of ensuring a minimum degree of contact between the stabilizing gas and the through the 'part 68- " emerging melt, to worry.

A receiving body 69 is mounted on the lateral projection 63. solidifies and surrounds a crucible 70 with a bottom 71 supported by the anisotropic plate 62. A crucible wall 72 and the bottom 71 'form one Container or an upper basin for the melt 75. The center of the bottom 71 and the part 68 form a lower one Basin with a smaller capacity. As mentioned earlier, the 'temperature of the melt is in the lower Basins usually kept higher than the melt temperature in the upper pelvis.

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The receiving body 69 is of a helical shape wound induction coil, -74 surrounded, -whose lower turns used as part of a line of force concentrator 75 will. A line part 76 in the; Kind of a washer. 'disc., is -on the inner .winding of the. coil 74 in the. same way attached ,, as. it in conjunction with the. \ Line of Force Concentrator the Pig. 2 and 3-described. That in Pig. 4 'illustrated integral part 76 surrounds the lateral projection 63 of the anisotropic plate 62. /. .

• During operation, the coil 74 is of a suitable,. th, not shown power source fed. The electromagnetic lines of force reach the circumferential area of the lateral projection 63 and into the receiving body 69. As indicated by the arrows 77, the heat is transmitted along the lateral projection 63 to the cable 65. Since the lower part of the anisotropic plate 63 is not in contact with the line of force concentrator 75, the walls of the chamber 64 which delimit the lower region, and consequently also the part 68, can easily be kept at temperatures which are suitable for the operation of the spinning device are. As before, the temperature gradient along the bottom of the crucible 70 is essentially eliminated. The spray opening 66 is at least as hot as the surrounding area. Bending melt due to the thermal conductivity properties of the anisotropic plate 62. -:; , _{BATH 0RIG1WAL}

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The spinning devices of Figures 2 and 4 are similar to the Pig spinning device. 1, so that in the following summary, for the sake of simplicity and brevity .. on the apparatus' after the i ^r ig. 1 is referred to. In order to melt the spin charge, heat is induced in the receiving body 12 and in the circumferential area of the thermally anisotropic plate 11. The plane of high thermal conductivity of the anisotropic plate 11 lies essentially parallel to the lower surface of the base plate 14 and therefore essentially perpendicular to the longitudinal axis of the spinning device. The thermal profile over the upper surface of the anisotropic plate 11 has due to the anisotropic properties ^; the plate 11 has an almost constant temperature. The constant temperature prevents significant temperature gradients from occurring in the base plate 14 and a possible thermal breakage occurring. At the same time, heat is transferred to the points on the surface of the anisotropic plate 11 which are closest to the opening 19, which tends to to be the coldest point in the crucible. 13 the dedication of the hot surface of the anisotropic plate 11 at the aperture 19 is used to maintain the temperature of the 'opening 19 to an optimum value. such a value is at or above the temperature of the surrounding -

j
the melt.

The anisotropic plate can be designed. that

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heat transfer only takes place in the areas that of the top surface of the anisotropic plate at lying next. In the case of an embodiment, hats be provided? which extends vertically upwards through the a-b plane of the-anisotropic plate to the desired one Extend the area of heat transfer. At .-- "one, another Embodiment, the upper region of the anisotropic plate has a lateral projection, so that only the Lateral projection intersects the magnetic line of force of the induction coil. It can also be a line of force concentrator can be used to concentrate the lines of force in the upper peripheral area of the aniso-tropi plate. With each of the above ... arrangements, the result is the same as the heat transfer takes place only in the upper Area of the anisotropic plate instead of *

From the above it can be seen that the tasks set have been achieved. Based on the above examples, games explained invention should · many forms of modification and modifications within the skill of the average person make possible. All of these alterations and amendments should be in accordance with the general jjrr- '" thought through, the adjoining alis under Protection will be provided. . ' "-

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Claims (7)

Patent claims: Apparatus with a crucible arrangement for spinning a thin liquid melt in the form of a fine stream, characterized by a part with a spinning opening by an anisotropic plate which is substantially parallel to the aforementioned part and a D; arch occurs and is aligned with its passage coaxially to the ■ spinning opening and one level higher Has thermal conductivity that extends from the peripheral area of the ahisotropic plate to the aforementioned passage extends, and has an area in the vicinity of the aforementioned passage, which is in thermal contact with an area of the aforementioned part in the vicinity the spinning orifice, and by heating devices for heating the peripheral area of the aforesaid anisotropic plate. 2. Device according to claim 1, characterized in that that it contains pyrolytic graphite. 3. Apparatus according to claim 1 or 2, characterized in that the part of the bottom is a melting pot is, which contains the liquid melt and im - 30 009841/1385 is essentially in physical contact with the thermally anisotropic plate, whose plane is with the high thermal conductivity runs essentially parallel to the bottom of the crucible. 4. Apparatus according to claim 1, 2 or 3, characterized in that the crucible has a separate vertical wall part which is carried by the floor, the wall part and the floor having overlapping surfaces in the area of mutual contact to avoid the leakage of melt. 5. Apparatus according to claim 4, characterized in that that the crucible at least at the contact surfaces is ceramic with the melt. 6. Apparatus according to claim 5, characterized in that the ceramic material is alumina, beryl alumina or zirconia> - ■ ---' --- _ 7. Device according to one of claims 1-6, characterized characterized in that the part is in the vicinity of the spinning orifice and the area near the passage je ^ because they touch a second heat conducting part. 009941 / -1 385 '2OV / 260 8 * Device according to one of claims 1 - 7, characterized in that: the anisotropic plate and the; part are essentially cylindrical and the anisotropic; tropisefee plate surrounds the part. :. ~ \ ~ 9 * device.according to one of claims 1 - 8 ^ characterized in that that the part is a crucible surrounded by a receiving body and a heater is, which is an induction coil in Porm a Helical line around the take-up body and the outer uniform of the anisotropic plate and has turns whose mutual spacing is as high as that of the anisotropic Plate is smaller than around the recording 3Ϊ Blank page