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CN-121972748-A - Cross rib light-weight structure and brazing manufacturing method

CN121972748ACN 121972748 ACN121972748 ACN 121972748ACN-121972748-A

Abstract

A cross rib lightweight structure and a brazing manufacturing method belong to the technical field of aircraft manufacturing. The brazing manufacturing method comprises the steps of carrying out pre-welding processing on a skin and ribs, forming T-shaped joints at two ends of the ribs, arranging grooves which are mutually spliced in cross intersection areas of the ribs, arranging a plurality of bosses at two sides of the grooves at intervals, repairing the ribs before welding, cleaning before welding, fixing cross ribs, adding cross rib brazing filler metal, adding skin brazing filler metal, fixing the skin and the cross ribs, heating a workpiece to be welded to a brazing temperature T at a certain heating rate, preserving heat for a period of time, cooling the workpiece to a low temperature along with a furnace after the heat preservation is finished, opening the furnace door, enabling vacuum requirements to be less than 8X 10 ‑3 Pa in the brazing process, and discharging the workpiece after the furnace door is opened for cooling. According to the brazing manufacturing method, the T-shaped joint is used for welding with the skin, so that the brazing welding area is remarkably increased, the brazing strength is improved, and the problem that brazing filler metal falls off or runs off is solved by arranging the boss.

Inventors

  • XU MING
  • Chang Chuanchuan
  • GAO XINGQIANG
  • Shi Haoxue
  • DENG YUNHUA

Assignees

  • 中国航空制造技术研究院

Dates

Publication Date
20260505
Application Date
20260408

Claims (10)

  1. 1. The utility model provides a brazing manufacturing method of crisscross rib lightweight structure, crisscross rib lightweight structure includes a plurality of ribs that the crisscross set up and is located the covering of rib both sides, its characterized in that, brazing manufacturing method includes the following step: S1, performing pre-welding processing on the skin and the ribs according to a part drawing, wherein the ribs adopt plates with the thickness of more than 3 times of the wall thickness to form T-shaped joints at two ends of the ribs in a machining mode, the wall thickness of the ribs is D, the brazing interface width D of the T-shaped joints is more than or equal to 2D, grooves which are mutually spliced are arranged in the cross intersection area of the ribs, the depth of the grooves is not less than half of the height of the ribs, and a plurality of bosses which prevent brazing filler metal from falling off under the action of gravity are arranged at two sides of the grooves at intervals; s2, repairing the ribs before welding, namely splicing the ribs and pre-assembling the ribs into a crisscross structure; s3, cleaning before welding, namely removing greasy dirt and metal scraps on the surface of the skin and the rib wallboard by adopting cleaning equipment; s4, fixing the crossed ribs, namely fixing the crossed connection areas of the ribs by spot welding through a welding machine by using a titanium alloy or stainless steel foil belt; S5, adding the cross rib solder, namely adding powder or paste solder into the cross connection area; S6, adding skin brazing filler metal, namely adding amorphous foil-tape brazing filler metal in a skin to-be-welded area; S7, fixing the skin and the crisscrossed ribs by using titanium alloy or stainless steel foil strips, and performing spot welding and fixing on the ribs and the skin by using a welding machine; S8, brazing and assembling into a furnace, namely heating the assembled workpiece to be welded to a brazing temperature T at a certain heating rate, preserving heat for a period of time, cooling to a low temperature along with the furnace after the heat preservation is finished, and then opening a furnace door, wherein the vacuum degree requirement in the brazing process is less than 8 multiplied by 10 -3 Pa; And S9, discharging the brazing, namely discharging the workpiece after the workpiece is opened and cooled.
  2. 2. The method for manufacturing the braze welding of the lightweight structure of the crisscross ribs according to claim 1, wherein the range of the flanging thickness h of the T-shaped joint is d/2-d, and d is the wall thickness of the ribs.
  3. 3. The method for manufacturing the cross rib lightweight structure by brazing according to claim 1, wherein the distance between the bosses is 4-6 times the thickness of the bosses.
  4. 4. The method of manufacturing a lightweight cross-rib braze of claim 1, wherein the T-joint and rib junction is a fillet transition.
  5. 5. The method of manufacturing a lightweight cross-rib brazing structure according to claim 1, wherein the boss is formed on the rib by machining.
  6. 6. The method of manufacturing a lightweight cross-rib structure for brazing of claim 1, wherein the skin is made of 2mm thick TA15 sheet material and the ribs are made of 6mm thick TA15 sheet material.
  7. 7. The method for manufacturing the cross rib lightweight structure according to claim 1, wherein after the brazing is performed out of the furnace, ultrasonic nondestructive inspection is performed on the workpiece, and the brazing welding rate of the workpiece is more than 95%.
  8. 8. The method for manufacturing the braze welding of the lightweight structure of the crisscross tendons according to claim 1, wherein the thickness tolerance of the tendons is-0.05 mm to +0.05mm.
  9. 9. The method of manufacturing a lightweight cross-rib structure for brazing as in claim 1, wherein the skin is greater than 1000 x 1000mm in size.
  10. 10. A cross rib lightweight structure is used for an aircraft component and is characterized by comprising a plurality of ribs arranged in a cross manner and skins positioned on two sides of the ribs, T-shaped connectors are arranged at two ends of the ribs, wherein the wall thickness of the ribs is D, the brazing interface width D of the T-shaped connectors is more than or equal to 2D, grooves which are mutually spliced are arranged in cross intersection areas of the ribs, the depth of each groove is not less than half of the height of each rib, a plurality of bosses which prevent brazing filler metal from falling off under the action of gravity at the brazing temperature are arranged on two sides of each groove at intervals, and the aircraft component is manufactured by using the brazing manufacturing method according to any one of claims 1 to 9.

Description

Cross rib light-weight structure and brazing manufacturing method Technical Field The invention relates to the technical field of aircraft manufacturing, in particular to a cross rib lightweight structure and a brazing manufacturing method. Background Some components of an aircraft are made up of a plurality of ribs arranged crosswise and skins on either side of the ribs. The crisscrossed ribs are welded to each other in a frame structure and are welded to the skin as a whole. The structure is long-time in service in severe environments such as high temperature, vibration and the like, and is required to have high rigidity, high temperature resistance, good vibration fatigue resistance and the like. The crisscross rib light-weight structure has the technical advantages of high specific strength, high specific rigidity and the like, but aiming at the side wall structure of the rear body of the large-size aircraft engine with the size exceeding 1500mm multiplied by 800mm multiplied by 150mm, the following technical problems still exist at present: (1) The panel and the crisscross ribs are in the form of T-shaped braze joints, the braze joint strength of the panel and the welding area are positively related, the welding area is mainly dependent on the wall thickness dimension of the crisscross ribs, the wall thickness of the sandwich structure is generally designed to be about 1.5 or 2mm, the ribs are in approximate line contact with the upper panel and the lower panel in the welding process due to the large size of the part, the pressure is not beneficial to braze welding, the braze joint interface area is small, the joint strength is low, and if the wall thickness of the ribs is increased, the overall weight of the component is obviously increased. (2) The height of the crossed ribs exceeds 100mm, the addition amount of the brazing filler metal can directly influence the strength of a brazing joint, the brazing filler metal is added in a conventional mode, the brazing filler metal is melted at the brazing temperature, on one hand, the risk of falling off of the brazing filler metal can occur under the action of gravity, on the other hand, the brazing filler metal is lost at the top of the sandwich structure, the risk of non-welding defects occurs, the brazing filler metal is accumulated at the bottom, and the root joint is brittle. The invention discloses a grid reinforcement wallboard for an aircraft structure, a forming die and a forming method of the grid reinforcement wallboard, and particularly discloses a grid reinforcement wallboard which comprises a grid frame, wherein a skin plate is arranged on the grid frame, the skin plate comprises an outer skin arranged on the bottom surface of the grid frame and an inner skin arranged on the grid frame, the grid frame comprises a transverse rib core material and a longitudinal rib core material which are connected, the inner skin is positioned between the transverse rib core material and the longitudinal rib core material, the connection position between the transverse rib core material and the longitudinal rib core material is called as a connection node, forming blocks are arranged on each connection node, the forming blocks are preformed bodies composed of carbon fibers and resin blocks, the forming blocks comprise reinforcing pieces which are distributed up and down, the reinforcing pieces comprise a top plate and limiting blocks arranged at the bottom of the top plate, the limiting blocks form slots for inserting the transverse rib core material and the longitudinal rib core material, and a shearing port is arranged in a corner area of the inner skin. In this solution, the presence of the inner skin will increase the weight of the structure, although the strength is improved, due to the need to provide an outer skin and an inner skin. The Chinese patent No. 214190067U discloses a co-cured longitudinal and transverse reinforced composite integral wallboard, which comprises a co-cured component and an inner edge of an L-shaped common frame, wherein the co-cured component is formed by co-curing a skin, T-shaped stringers and outer edges of the T-shaped common frame, the outer edges of the T-shaped stringers and the T-shaped common frame are distributed on the surface of the skin in a crisscross manner, and the inner edge of the L-shaped common frame is fixed with the outer edge of the T-shaped common frame. The scheme improves the integrity of the skin and the longitudinal and transverse reinforced composite material, reduces the structural weight, but the composite material is required to be used, and is not suitable for occasions where metal materials such as titanium alloy are used as ribs. Disclosure of Invention The invention provides a cross rib lightweight structure and a brazing manufacturing method, so as to at least partially solve the technical problems. As a first aspect of the present invention, there is provided a brazing manufacturing method o