Developments and perspectives on the precision forming processes for ultra-large size integrated components

Abstract

In order to meet the requirements of high reliability, long-lifetime and lightweight in a new generation of aerospace, aviation, high-speed train, and energy power equipment, integrated components are urgently needed to replace traditional multi-piece, welded components. The applications of integrated components involve in a series of large-size, complex-shaped, high-performance components made of difficult-to-deform materials, which present a huge challenge for forming ultra-large size integrated components. In this paper, the developments and perspectives of several extreme forming technologies are reviewed, including the sheet hydroforming of ultra-large curved components, dieless hydroforming of ellipsoidal shells, radial-axial ring rolling of rings, in situ manufacturing process of flanges, and local isothermal forging of titanium alloy components. The principle and processes for controlling deformation are briefly illustrated. The forming of typical ultra-large size integrated components and industrial applications are introduced, such as the high strength aluminum alloy, 3 m in diameter, integrated tank dome first formed by using a sheet blank with a thickness the same as the final component, and a 16 m diameter, integrated steel ring rolled by using a single billet. The trends for extreme forming of ultra-large size integrated components are discussed with a goal of providing ideas and fundamental guidance for the further development of new forming processes for extreme-size integrated components in the future.

Study on cryogenic deep drawing of 2219 aluminum alloy spherical shell

“…With high strength-to-weight ratio, excellent fracture toughness, and good corrosion resistance [1][2][3] , aluminum alloys have been widely used in the manufacture of curved shell in aviation, aerospace, automotive, and marine fields, such as the bottom of launch vehicle fuel tanks, aircraft skins, body coverings of automotive, and ship-shaped deep-cavity components [4][5][6] . Since the significant improvement of the new generation equipment for high reliability, long life and light weight, there is an urgent need to replace the traditional multi-piece tailor-welded structure with an integral structure [7] [8] . Such integral thin shell is a kind of large-size curved surface components.…”

Testing technology for tensile properties of metal materials based on deep learning model

“…When the stretching speed is increased, applying 200 kN tension to the metal material will cause dislocation intensive reduction of the material tensile properties and fracture of the metal material. Yuan and Fan ( 2019 ) found that a reasonable choice of speed and pressure is required when stretching metal materials. When the metal is stretched, this operation needs to ensure that the metal crystal slip is produced and the tensile properties of the material are taken into account.…”

The influence of pH and H2O2 on surface quality and material removal rate during W-CMP

“…Due to its excellent properties, such as high melting point (3410 ± 10 ℃), high hardness, high thermal conductivity, high temperature strength, low coe cient of thermal expansion and so on [1][2][3], tungsten (W) is widely used in the aerospace, military industry, optical manufacturing, nuclear reactors, medical devices and other elds [4][5][6][7]. For example, in the eld of optical manufacturing, W has become an ideal material for the manufacture of molds for ultra-precise glass parts [8].…”