RU2722211C1 - Spiral manufacturing method for twt retardation system - Google Patents

Abstract

FIELD: electronic equipment.SUBSTANCE: invention relates to the field of electronic equipment, namely to spiral slow-wave systems of traveling-wave tubes (TWT). Making the slow-wave systems for the TWT retardation system comprises the steps of winding the metal band onto the rotating inner mandrel, degreasing, cleaning, moulding annealing and spiral release from the internal mandrel, at that, the spiral is wound from two tapes - tapes from refractory metal, for example, tungsten or molybdenum, and metal bands with high plasticity and electrical conductivity, for example, copper or composite material based on copper. When performing the winding of these tapes on the rotating internal mandrel, these tapes are wound on the internal mandrel simultaneously, wherein refractory metal tape is wound directly on inner mandrel, and tape from metal with high plasticity and electric conductivity is wound on internal mandrel over tape from refractory metal, providing in spiral tight attachment of this tape to tape from refractory metal. After winding ends of spiral are fixed on inner mandrel, unused parts of metal bands are cut off, from which spiral is wound, and degreasing is performed and spiral is cleaned on inner mandrel. Then, without removing from the inner mandrel, the defatted and cleaned spiral is placed in the other, external to the spiral, mandrel from material with a lower coefficient of thermal expansion than the metal with high plasticity and electrical conductivity, from which the external spiral tape is made; fixing the spiral with internal mandrel in external mandrel with provision of tight fit of internal surface of external mandrel enveloping spiral, to external surface of spiral. Then forming spiral annealing is performed, thermal reduction of part of spiral from metal band with high plasticity and electric conductivity and diffusion welding of helically wound ribbons from tape with metal band with high plasticity and electroconductivity at low pressure - no more than 10mm of mercury (1.33⋅10Pa), forming temperature of part of spiral from refractory metal and thermal reduction of part of spiral from tape from metal with high plasticity and electrical conductivity 880–930 °C for 15–20 minutes and temperature of diffusion welding 550–600 °C for 30–40 minutes. During moulding of spiral annealing at temperature of 880–930 °C, due to difference in coefficients of thermal expansion of material of outer mandrel and metal with high ductility and electrical conductivity, thermal reduction of part of spiral from metal band with high ductility and electric conductivity. When temperature is reduced to 550–600 °C, tapes wound in a spiral are squeezed due to difference in coefficients of thermal expansion of refractory metal and metal with high ductility and electrical conductivity. At that, all necessary conditions for diffusion welding are provided. Under the conditions obtained under low pressure, compression of welded metals and temperature during 30–40 minutes, diffusion welding of ribbons from refractory metal and metal with high plasticity and electroconductivity along their common boundary is performed. After moulding of spiral annealing and diffusion welding of tapes wound on inner mandrel, spiral is released from mandrels at normal temperature and atmospheric pressure and spiral is re-cleaned.EFFECT: manufacturing of spiral for TWT retarding system, reduction of spiral temperature, reduction of losses of UHF power in slow-wave systems, increased service life of TWT, increased contour and general efficiency of TWT.4 cl, 3 dwg

Description

The invention relates to the field of electronic technology, namely to spiral slowdown systems of traveling wave tubes (TWT).

A known method of manufacturing a tape spiral from wire, including the operation of flattening the wire into a tape and winding the tape onto a rotating core [G.O. Volik, A.P. Ilyin, Yu.A. Kurdin, I.I. Poles. Copyright Certificate No. 579081, Publ. 11/05/1977. Bulletin No. 41. Description publ. 11/18/1977].

However, the disadvantage of this method of manufacturing a tape spiral for a retarding system (ZS) is that with this method it is impossible to make a spiral from a bimetallic tape consisting of a refractory metal (for example, tungsten or molybdenum), which has high hardness and elasticity, and from metal having high ductility and conductivity (for example, copper or copper-based composite material). Spirals made of a single refractory metal, due to the high hardness of the material and, as a consequence, the absence of its plastic deformation, do not allow thermal contacts of the spiral with dielectric rods in the ZS with an area close to the area of the projection of the spiral on dielectric rods at their intersection and contact . This reduces the efficiency of heat removal from the ZS helix during TWT operation. Spirals made of a single metal having high ductility, due to the low shape stability of the material, also do not allow thermal contacts of the spiral with dielectric rods in ZS with an area close to the area of the projection of the spiral on dielectric rods at their intersection and contact, which also reduces the efficiency of heat removal from the ZS spiral during TWT operation. A decrease in the efficiency of heat removal from the ZS spiral during TWT operation leads to an increase in the temperature of the spiral and loss of microwave power in the ZS, reduction in the life of the TWT, and a decrease in the contour and overall efficiency of the TWT.

There is also known a method of manufacturing a spiral of molybdenum or tungsten wire with a diameter of 0.03 to 0.5 mm or of molybdenum or tungsten wire coated with silver 0.0005 mm thick to increase surface electrical conductivity. The method includes winding the wire onto a rotating mandrel, degreasing, cleaning, molding annealing and removing the spiral from the mandrel [M.B. Golant, A.A. Maklakov, M.B. Shur "Production of resonators and retardation systems of electronic devices" // Ed. "Soviet Radio" M. 1969. S. 325-327].

The disadvantage of this method of manufacturing spirals for ZS is that spirals made of molybdenum or tungsten wire, due to the high hardness of the material and, consequently, the absence of its plastic deformation, do not allow thermal contacts of the spiral with dielectric rods in the ZS with an area close to the area of the projection of the spiral onto the dielectric rods at the points of their intersection and contact. This reduces the efficiency of heat removal from the ZS helix during TWT operation. Spirals made of molybdenum or tungsten wire with a diameter of 0.03 to 0.5 mm or of molybdenum or tungsten wire coated with silver with a thickness of 0.0005 mm to increase the surface conductivity also do not allow thermal contacts of the spiral with dielectric rods in ZS with an area close to the area of the projection of the spiral onto the dielectric rods at the points of their intersection and contact. In addition, due to the high temperature of the ZS helix and the influence of electrons in the electron beam during TWT operation, silver is sprayed from the surface of the helix and deposited on the dielectric rods of the ZS, which increases the microwave power loss in the ZS. A decrease in the efficiency of heat removal from the ZS helix and an increase in the losses of microwave power in the ZS due to sputtering and subsidence on the dielectric rods of the ZS of silver during TWT operation leads to an increase in the temperature of the spiral and losses of microwave power in the ZS, decrease in the service life of the TWT, and decrease in loop and total efficiency of TWT.

Closest to the proposed invention is a method for manufacturing a tape spiral of a deceleration line, comprising the steps of manufacturing a tape and winding the tape onto a rotating core. The tape is made of materials with different ductility, while a material with less ductility (for example, tungsten, molybdenum, etc.) in the form of two or more wires of circular cross section located in parallel and in a certain configuration relative to each other, are interconnected by a material, having greater ductility and less ohmic resistance (for example, gold, silver, copper) by passing round cross-section wires through a forming die, immersed in a material melt with greater ductility [V.G. Poppy, V.Ya Chaban. Copyright Certificate No. 1787633, Publ. 01/15/1993. Bulletin No. 2].

The disadvantages of this method of manufacturing a tape spiral of the deceleration line are: the complexity and low manufacturability of the manufacture of tape from materials with different ductility; the presence on the surface of the tape of wires of circular cross-section made of a material with less ductility (for example, tungsten, molybdenum, etc.) that do not allow obtaining thermal contacts of the spiral with dielectric rods in the CS with an area close to the area of the projection of the spiral onto dielectric rods at their intersections and contact; spraying on the dielectric rods of ZS material with greater ductility and lower ohmic resistance (for example, gold, silver, copper), from the inner surface of the spiral, subjected to electronic bombardment during TWT operation. All this leads to an increase in the temperature of the spiral, an increase in the loss of microwave power in the ES, a decrease in the life of the TWT, and a decrease in the circuit and overall efficiency of the TWT.

The technical result of the present invention is to reduce the complexity and increase the manufacturability of the spiral for the retardation TWT system, reduce the temperature of the spiral, reduce the loss of microwave power in the AP, increase the service life of the TWT, increase the contour and overall efficiency of the TWT.

The technical result is achieved by the fact that the manufacture of a spiral for the TWT retarding system includes the operations of winding a metal tape onto a rotating inner mandrel, degreasing, cleaning, molding annealing and releasing the spiral from the inner mandrel, while the spiral is wound from two tapes - refractory metal bands (for example , tungsten or molybdenum) and metal tapes with high ductility and electrical conductivity (for example, copper or copper-based composite material). When performing the operation of winding these tapes onto a rotating inner mandrel, these tapes are wound onto the inner mandrel at the same time, and the tape from refractory metal is wound directly onto the inner mandrel, and the tape from metal with high ductility and electrical conductivity is wound onto the inner mandrel over the tape from refractory metal, providing in a spiral tight fit of this tape to a tape of refractory metal. After winding, the ends of the spiral are fixed on the inner mandrel, the unused parts of the metal strips are cut off, of which the spiral is wound and the spiral is degreased and cleaned on the inner mandrel. Then a fat-free and cleaned spiral is placed, without releasing it from the inner mandrel, into another mandrel made of a material with a lower coefficient of thermal expansion than the metal with high ductility and electrical conductivity, of which the outer spiral strip is made; they fix the spiral with the inner mandrel in the outer mandrel with a tight fit of the inner surface of the outer mandrel covering the spiral to the outer surface of the spiral. Then a molding annealing of the spiral is carried out, thermal compression of the part of the spiral from a metal tape with high ductility and electrical conductivity and diffusion welding of a coil of refractory metal wound into a spiral from a metal tape with high ductility and electrical conductivity under reduced pressure is carried out - not more than 10 ^-3 mm RT. Art. (1.33⋅10 ^-1 Pa), the temperature of forming a part of a spiral of refractory metal and the thermal reduction of a part of a spiral of metal tape with high ductility and electrical conductivity of 880-930 ° C for 15-20 minutes and the temperature of diffusion welding 550-600 ° C for 30-40 minutes In the process of molding annealing of the spiral at a temperature of 880-930 ° C, due to the difference in the coefficients of thermal expansion of the material of the outer mandrel and metal with high ductility and electrical conductivity, thermal compression of a part of the spiral from a metal tape with high ductility and electrical conductivity is carried out. When the temperature drops to 550-600 ° C, the tapes are wound in a spiral due to the difference in the coefficients of thermal expansion of the refractory metal and the metal with high ductility and electrical conductivity. In this case, all the necessary conditions for diffusion welding are provided. Under the obtained conditions for reduced pressure, compression of the metals being welded and temperature, diffusion welding of coils of refractory metal and metal with spiral ductility with high ductility and electrical conductivity along their common boundary takes place during 30-40 minutes. After molding annealing of the spiral and diffusion welding of the tapes wound on the inner mandrel, the spiral is freed from the mandrels at normal temperature and atmospheric pressure and the spiral is again cleaned.

The invention is illustrated by drawings.

In FIG. 1 shows a spiral winding diagram. In FIG. 2 shows a spiral wound on a mandrel. In FIG. Figure 3 presents one of the possible options for securing a spiral with an internal mandrel in an external mandrel.

With reference to FIG. 1 - FIG. 3 is indicated:

1 - inner mandrel;

2 - a spiral;

3 - tape of refractory metal;

4 - metal tape with high ductility and electrical conductivity;

5 - external mandrel.

A method of manufacturing a spiral for the TWT retarding system is carried out as follows: a spiral (2) of two tapes is wound onto a rotating inner mandrel (1) - tapes of refractory metal (for example, tungsten or molybdenum) (3) and tapes of metal with high ductility and electrical conductivity (e.g., copper or copper-based composite material) (4); during the operation of winding the tape (3) and tape (4) onto a rotating inner mandrel (1), these tapes are wound onto the inner mandrel (1) at the same time, and the tape from refractory metal (3) is wound directly onto the inner mandrel (1), and a metal tape with high ductility and electrical conductivity (4) is wound onto an inner mandrel (1) over a tape of refractory metal (3), providing in a spiral (2) a snug fit of this tape (4) to a tape of refractory metal (3); fix the ends of the spiral (2) on the inner mandrel (1); unused parts of metal strips (3) and (4) are cut off, of which a spiral (2) is wound; degreasing and cleaning the spiral (2) on the inner mandrel (1); without degreasing from the inner mandrel (1), place a defatted and cleaned spiral (2) in another mandrel (5) external to the spiral (2) from a material with a lower coefficient of thermal expansion than a metal with high ductility and electrical conductivity of the tape (4); securing the spiral (2) with the inner mandrel (1) in the outer mandrel (5) to ensure that its inner surface snugly surrounds the spiral (2) to the outer surface of the spiral (2); carry out molding annealing of the spiral (2) and thermal compression of the spiral part (2) from a metal tape with high ductility and electrical conductivity (4) under reduced pressure - not more than 10 ^-3 mm Hg (1.33⋅10 ^-1 Pa), the temperature of forming a part of a spiral from a strip of refractory metal (3) and thermal reduction of a part of a spiral from a strip of metal with high ductility and electrical conductivity (4) 880-930 ° С for 15-20 min; reduce the temperature of the spiral (2) with the inner mandrel (1) in the outer mandrel (5) to 550-600 ° C and hold the spiral (2) with the inner mandrel (1) in the outer mandrel (5) for 30-40 minutes at reduced pressure - not more than 10 ^-3 mm Hg (1.33⋅10 ^-1 Pa) and a temperature of 550-600 ° C, with the provision of diffusion welding of ribbons made of refractory metal (3) wound onto an internal mandrel (1) in a spiral (2) with a ribbon of metal with high ductility and electrical conductivity (4); carry out the release of the spiral (2) from the external (5) and internal mandrels (1) at normal temperature and atmospheric pressure; re-clean the spiral (2).

Sources of information

1. G.O. Volik, A.P. Ilyin, Yu.A. Kurdin, I.I. Poles. Copyright Certificate No. 579081, Publ. 11/05/1977. Bulletin No. 41. Description publ. 11/18/1977.

2. M.B. Golant, A.A. Maklakov, M.B. Shur "Production of resonators and retardation systems of electronic devices" // Ed. "Soviet Radio" M. 1969. S. 325-327.

3. V.G. Poppy, V.Ya Chaban. Copyright Certificate No. 1787633, Publ. 01/15/1993. Bulletin No. 2.

Claims (4)

1. A method of manufacturing a spiral for the TWT retarding system, including the operation of winding a metal tape onto a rotating inner mandrel, degreasing, cleaning, molding annealing and releasing the spiral from the mandrel, characterized in that the spiral is wound from two tapes - refractory metal tapes and tapes made of metal with high ductility and electrical conductivity; during the operation of winding these tapes onto a rotating inner mandrel, these tapes are wound onto the inner mandrel at the same time, and the tape from refractory metal is wound directly onto the inner mandrel, and the tape from metal with high ductility and electrical conductivity is wound onto the inner mandrel over the tape from refractory metal, providing in a spiral tight fit of this tape to a tape of refractory metal; fix the ends of the spiral on the inner mandrel; cut off unused parts of metal strips from which a spiral is wound; degreasing and cleaning the spiral on the inner mandrel; without degreasing from the inner mandrel, place a non-fat and cleaned spiral in another mandrel made of a material with a lower coefficient of thermal expansion than the metal with high ductility and electrical conductivity, of which the outer spiral strip is made; securing the spiral with the inner mandrel in the outer mandrel with a tight fit of the inner surface of the outer mandrel covering the spiral to the outer surface of the spiral; carry out molding annealing of the spiral and thermal compression of the part of the spiral from a metal tape with high ductility and electrical conductivity under reduced pressure - not more than 10 ^-3 mm Hg (1.33 · 10 ^-1 Pa), the temperature of forming a part of a spiral from a strip of refractory metal and thermal reduction of a part of a spiral from a tape of metal with high ductility and electrical conductivity of 880-930 ° C for 15-20 minutes; reduce the temperature of the spiral with the inner mandrel in the outer mandrel to 550-600 ° C and hold the spiral with the inner mandrel in the outer mandrel for 30-40 minutes at reduced pressure - not more than 10 ^-3 mm Hg (1.33 · 10 ^-1 Pa) and a temperature of 550-600 ° C, with the provision of diffusion welding of a strip of refractory metal wound onto a mandrel in a spiral with a metal tape with high ductility and electrical conductivity; carry out the release of the spiral from the external and internal mandrels at normal temperature and atmospheric pressure; re-clean the spiral. 2. A method of manufacturing a spiral for the TWT retarding system according to claim 1, characterized in that a tungsten tape is used as a tape from refractory metal, and a copper tape is used as a tape from metal with high ductility and electrical conductivity. 3. A method of manufacturing a spiral for the TWT retarding system according to claim 1, characterized in that a molybdenum tape is used as a tape from a refractory metal, and a copper tape is used as a tape from a metal with high ductility and electrical conductivity. 4. A method of manufacturing a spiral for the TWT retarding system according to claim 1, characterized in that a tape made of a copper-based composite material is used as a metal tape with high ductility and electrical conductivity.

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