Production and preparation process of aviation O-state coated 7-series aluminum alloy skin thin plate

Abstract

A production and preparation process of an aviation O-state coated 7-series aluminum alloy skin thin plate comprises the following steps that 1, a coating material is attached to a cast ingot, the distance between the periphery of the coating material and the edge of the cast ingot is 20-30 mm, fixing and welding are conducted in a bolt fastening manner every 1000-1500 mm in the length direction, and a welding material adopts 7075-F-state aluminum alloy; 2, the composite aluminum material of the coating material and the cast ingot in the step 1 is heated and hot-rolled; 3, the plate with the thickness ranging from 7.0 mm to 8.0 mm is subjected to three times of cold rolling till the thickness ranges from 3.25 mm to 4.75 mm; and 4, the cold-rolled plate is subjected to heat preservation for 2 h at the temperature of 370 DEG C-380 DEG C, the temperature is reduced to 150 DEG C or below, the cooling rate is reduced to be less than or equal to 15 DEG C / h, and the O-state coated aluminum thin plate is obtained after cooling. According to the production and preparation process, the various performance indexes of the 7075 alloy O-state coated thin plate for civil aircraft skin comprehensively meet the performance requirements of the AMS4048 standard are developed through the technical means of alloy component optimization, composite casting and welding processes, cold rolling and hot rolling processes and the like.

Description

technical field [0001] The invention belongs to the field of aerospace aluminum alloys, in particular to a production and preparation process of aviation O-state coated 7-series aluminum alloy skin sheets. Background technique [0002] Aircraft skin sheets are exposed to the environment for a long time, which requires high corrosion resistance and strength of materials. The 7075 aluminum alloy belongs to the Al-Zn-Mg-Cu series, which is a high-strength aluminum alloy. The cladding sheet gives the alloy a higher The anti-corrosion ability is enough to meet the design and use requirements of high safety and long life of the aircraft. Due to the lack of domestic experience in the development of aviation cladding sheets, domestic civil aviation aircraft skin materials are mainly imported from abroad. In the development process of the 7075 alloy O-state clad thin plate, there are difficulties such as easy cracks during the cladding rolling process, low thickness control accuracy...

AI Technical Summary

Problems solved by technology

In the development process of the 7075 alloy O-state clad thin plate, there are difficulties such as easy cracks during the cladding rolling process, low thickness control accuracy, poor surface quality, and performance that do not meet the standard requirements, so that the comprehensive performance of the subsequent application state cannot be achieved. Technical Design Requirements

[0004] 7075 alloy O-state clad sheet is supplied as a machinable state for large-scale civil aircraft skin sheet. However, the performance of the material in the prior art is not uniform during the preparation process, and it is prone to cladding cracks, uneven thickness of the cladding layer and control of the plate shape. Difficulties, etc. cannot well meet the requirements of the AMS 4048 standard, so it is necessary to systematically innovate in technologies such as alloy composition, cladding process and rolling process optimization

However, there is no mature set of production methods in China at present. In the actual production process, due to problems such as uneven thickness of the sheet and poor uniformity of the thickness of the clad aluminum, the performance of different positions of the overall sheet is quite different, which will also lead to occurrence during use. Cracking, deformation, etc., which have a greater impact on the service life of the wing skin

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