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CN-121988986-A - High-purity titanium metal diaphragm for aerospace propellant storage tank and preparation method thereof

CN121988986ACN 121988986 ACN121988986 ACN 121988986ACN-121988986-A

Abstract

The invention discloses a high-purity titanium metal diaphragm for a space propellant storage tank and a preparation method thereof, wherein the high-purity titanium with the content of titanium element not less than 99.995 percent in metal element is taken as a raw material, and the preparation method comprises the steps of forging, hot rolling, cold rolling and heat treatment are sequentially carried out on the high-purity titanium to obtain a high-purity titanium plate; the heat treatment is stepped multistage heat preservation heat treatment, stepped heat preservation is carried out at the temperature of 300-680 ℃ in a gradient manner, a high-purity titanium plate is processed and formed, heat treatment is carried out at the same time, and the formed plate is machined by adopting a double-sided processing technology, so that the titanium alloy plate is obtained. The obtained high-purity titanium metal membrane has lower tensile strength and yield strength, and greatly improves the elongation to 77.5%. The polygonal instability resistance pressure of the metal diaphragm is obviously improved in the overturning process, reliable overturning is realized, and the metal diaphragm can be better applied to a storage tank of a space liquid propeller.

Inventors

  • QIAO YANWEI
  • WANG TINGTING
  • QIAO LIN
  • GAO WENQIANG
  • WANG YU
  • LIU YINGHAN
  • SHI HUA

Assignees

  • 上海空间推进研究所

Dates

Publication Date
20260508
Application Date
20260127

Claims (10)

  1. 1. The preparation method of the high-purity titanium metal membrane is characterized by comprising the following steps of: s1, rolling a plate, namely forging, hot rolling, cold rolling and heat treatment are sequentially carried out on high-purity titanium to obtain a high-purity titanium plate; in the high-purity titanium, the content ratio of titanium element in metal elements is not less than 99.995%; The heat treatment is stepped multi-section heat preservation heat treatment, and stepped heat preservation with no less than 3 gradients is carried out within the range of 300-680 ℃; S2, forming a plate, namely processing and forming the high-purity titanium plate obtained in the step S1, and performing heat treatment at the same time; And S3, machining, namely machining the formed plate by adopting a double-sided machining technology to obtain the finished product.
  2. 2. The method according to claim 1, wherein in the step S1, the non-metallic impurity of high purity titanium contains not more than 0.03% of oxygen element, not more than 0.003% of carbon element, not more than 0.003% of hydrogen element, and not more than 0.003% of nitrogen element.
  3. 3. The preparation method according to claim 2, wherein the high purity titanium is prepared by vacuum refining and purifying using 0A grade titanium sponge as a raw material.
  4. 4. The method according to claim 1, wherein in step S1, the forging temperature is 750-900 ℃, and the titanium ingot is respectively upset and drawn 3-6 times after forging.
  5. 5. The method according to claim 1, wherein in step S1, the hot rolling is performed at a temperature of 630 to 850 ℃ and a number of times of rolling is 9 to 16, and the number of times of reversing rolling is not less than 4 when the plate is cut into square plates during rolling.
  6. 6. The method according to claim 1, wherein in step S1, the cold rolling is performed at 320-380 ℃ as an initial temperature, and is naturally cooled to room temperature during the rolling process, the number of times of rolling is 11-19, and the number of times of reversing rolling during the rolling process is not less than 3.
  7. 7. The method according to claim 1, wherein in step S1, the stepped multi-stage heat-insulating heat treatment comprises heat-insulating at 300-400 ℃ for 30-40 min, heat-insulating at 400-500 ℃ for 30-40 min, and heat-insulating at 600-680 ℃ for 30-40 min.
  8. 8. The method according to claim 1, wherein in step S2, the sheet is formed by any one of stamping, spinning, and superplastic forming.
  9. 9. The method according to claim 1, wherein in step S2, the temperature of the heat treatment is 530 to 700 ℃.
  10. 10. A high purity titanium metal diaphragm for a space liquid propellant tank, characterized in that the diaphragm is prepared by the preparation method according to any one of claims 1-9.

Description

High-purity titanium metal diaphragm for aerospace propellant storage tank and preparation method thereof Technical Field The invention relates to the technical field of manufacturing of space flight metal diaphragm storage tanks, in particular to a high-purity titanium metal diaphragm for a space flight propellant storage tank and a preparation method thereof. Background In the field of space propellant storage tanks, the metal membrane storage tank has the advantages of simple structure, mature process, capability of achieving physical isolation of pressurized gas and liquid propellant, excellent mechanical environment performance, wide discharge flow range and the like, and is widely applied to the fields of manned space, deep space exploration, weapons, satellites, carrying and the like. The working principle of the metal diaphragm is to realize stable supply of the propellant by means of orderly overturning of the metal diaphragm, so that the metal diaphragm is required to be stable and orderly in the overturning process and no leakage condition occurs. In the overturning process, the metal diaphragm has the characteristics of plasticity and large deformation, so that the raw material for manufacturing the metal diaphragm is required to have good toughness, high elongation and strong cold deformation capability. Titanium alloy materials are selected as materials for manufacturing the propellant reservoirs by virtue of their good compatibility and excellent properties in terms of processes such as welding, forming, etc. However, the alloy has high strength, low plasticity characteristics, which makes it unsuitable for use in metal diaphragms. Through years of research and development in China, a manufacturing path of the metal membrane is constructed by taking pure titanium or low-clearance pure titanium as a raw material, and the pure titanium or low-clearance pure titanium (the titanium content of the pure titanium is not less than 99.095 percent and the titanium content of the low-clearance pure titanium is not less than 99.55 percent) can realize stable overturning of the metal membrane, but the performance of the metal membrane is still deficient. For example, the material strength is higher, the plasticity is lower, and the pressure difference of the manufactured metal diaphragm is larger. To reduce the pressure difference, the wall thickness of the metal diaphragm needs to be reduced, and too thin wall thickness causes problems of instability in the overturning process and low resistance to the mechanical environment. In order to solve the problem of instability in the overturning process, a method for adding annular reinforcing ribs is needed, so that the complexity of processing is increased due to the addition of the reinforcing ribs, stress concentration is generated due to the fact that the geometric dimensions of the root parts of the reinforcing ribs are discontinuous in the overturning process, and the fracture risk is further caused. It follows that pure titanium or low-gap pure titanium is not the most desirable titanium metal diaphragm material. Disclosure of Invention Aiming at the demands of titanium metal membrane for space liquid propellant storage tanks on low strength and high plasticity of raw materials, the invention provides a high-purity titanium metal membrane for space liquid propellant storage tanks and a preparation method thereof, and the technical problems are successfully solved by controlling the components of high-purity titanium with ultrahigh titanium content and controlling a rolling process and a forming process. The high-purity titanium used in the invention is a titanium material with ultra-high purity (the titanium content is not less than 99.995% of the metal element content) obtained by a purification technology, and is widely applied to the semiconductor industry as a target material, but cannot be directly used for preparing a metal diaphragm. The invention takes high-purity titanium material as raw material for preparing metal membrane, which has ultra-low impurity element and gap element, and further prepares ideal metal membrane material with low tensile strength, low yield strength, high elongation and finer average grain size successfully through improvement of smelting, rolling and heat treatment processes. The technical scheme of the invention is as follows: In a first aspect, the invention provides a method for preparing a high-purity titanium metal membrane, which comprises the following steps: s1, rolling a plate, namely forging, hot rolling, cold rolling and heat treatment are sequentially carried out on high-purity titanium to obtain a high-purity titanium plate; in the high-purity titanium, the content ratio of titanium element in metal elements is not less than 99.995%; The heat treatment is stepped multi-section heat preservation heat treatment, and stepped heat preservation with no less than 3 gradients is carried out within the range of 30