Titanium alloy thin-wall seamless lining straight cylinder section superplastic forming wall thickness uniformity control method

Abstract

The invention discloses a titanium alloy thin-wall seamless lining straight cylinder section superplastic forming wall thickness uniformity control method, and belongs to the technical field of plastic processing. According to the method, a small-caliber lining spinning part with the variable wall thickness is adopted for conducting superplastic bulging, firstly, a thinning area is machined on a straight cylinder section of the lining spinning part, an original equal-thickness straight cylinder section is machined into a variable-wall-thickness pipe with the same annular direction and axial gradient distribution, and then superplastic bulging is conducted. According to the method of the invention, through the special wall thickness gradient design, the wall thickness distribution of the straight cylinder section of the bulged titanium alloy lining can be adjusted, a large-diameter lining blank with the thickness of the straight cylinder section being evenly distributed is obtained, the requirement for subsequent machining thinning wall thickness tolerance is met, meanwhile, control measures are taken for cooling of the lining blank, and the dimensional stability of the formed titanium alloy lining is ensured. The method is suitable for titanium alloy thin-wall seamless linings with various diameters, which are integrally formed by spinning / superplastic.

Description

technical field [0001] The invention belongs to the technical field of superplastic forming, and in particular relates to a preparation method of a novel titanium alloy thin-walled seamless lining. Background technique [0002] As a key component of the pressurized delivery system of aerospace models such as launch vehicles, strategic / tactical missiles, and deep space probes, the titanium alloy lining for composite gas cylinders usually adopts the "forging + welding" method, but with the development of aerospace models, It cannot meet the requirements in terms of reliability, weight reduction and advancement, so a new process is urgently needed to realize the continuous integrated forming of titanium alloy lining to replace the current process route. [0003] The titanium alloy lining precision spinning / superplastic forming integrated technology uses small-sized pipes as raw materials, and the two ends are closed and spun to form a weldless lining blank, and then superplasti...

AI Technical Summary

Problems solved by technology

However, in the process of superplastic forming, there is a sequence of contact between different positions of the cylindrical lining straight section and the superplastic mold. The wall thickness of the first contact position is slightly thicker, and the wall thickness of the second contact position is slightly thinner, resulting in a straight liner The wall thickness distribution of the section is uneven, and because the inner surface of the non-welded liner cannot be machined, it is easy to cause the wall thickness to be out of tolerance and fail to meet the precision requirements. Therefore, it is necessary to control the wall thickness uniformity of the superplastic forming of the liner straight section

However, there are no reports on the superplastic forming of titanium alloy seamless cylindrical linings using the bulging technology of variable wall thickness cylindrical parts, and have obtained relevant reports on engineering applications.

Images