Near-isothermal forging method of TC17 biphase titanium alloy disc forge piece

Abstract

The invention discloses a near-isothermal forging method of a TC17 biphase titanium alloy disc forge piece, comprising the steps of: heating a TC17 titanium alloy disposable bar ingot to 30-75 DEG C below a phase change point, upsetting the disposable bar ingot into a disposable circular cake; heating the disposable circular cake to 20-60 DEG C over the phase change point, and drawing out the disposable circular cake till the length thereof returns the length of the disposable bar ingot to obtain a secondary bar ingot; heating the secondary bar ingot to 30-75 DEG C below the phase change point, upsetting the secondary bar ingot to form a secondary circular cake, then punching to form an annular blank; and heating the annular blank to 20-60 DEG C over the phase change point, heating an upper forging mold and a lower forging mold to 10-20 DEG C below the phase change point, and forging and stamping the annular blank by the upper forging mold and the lower forging mold under the pressure of 30-60mN to make the deformation degree of the annular blank reach 30-50% in the forging molds at a strain rate of 0.001s-1 to 0.01s-1, and then forming a disc forge piece on fire, wherein the heat treatment after forging is the combination of solution treatment and ageing treatment. The disc forge piece forged by using the method has ideal electrical plating basket structure and high performance and is suitable for manufacturing forge pieces of an air compressor chassis, a turbine disc and the like of an aero-engine.

Description

[0001] This application is a divisional application of the patent application with the application number 200810069069.4, the application date is December 25, 2008, and the invention title is "near-isothermal forging method for two-phase titanium alloy disc forging". technical field [0002] The invention relates to a forging method of a titanium alloy forging, in particular to a nearly isothermal forging method of a TC17 two-phase titanium alloy disc forging. Background technique [0003] Due to the harsh working environment and complex stress, the compressor discs and turbine discs of aero-engines are often forged with α+β two-phase titanium alloys with excellent comprehensive properties, such as TC17 and BT25. The disc forged with α+β type titanium alloy has a series of advantages such as high strength, good fracture toughness, high hardenability and wide forging temperature range, which can meet the needs of damage tolerance design and high structure and high reliability....

AI Technical Summary

Problems solved by technology

[0004] In terms of the forging method of the two-phase titanium alloy, the Chinese invention patent specification CN1403622A published on March 19, 2003 discloses a titanium alloy quasi-beta forging process, which is used to perform quasi-beta forging on the α+β type two-phase titanium alloy At this time, the titanium alloy billet is heated to the region near the β transformation point temperature, that is, the range of 10°C below the transformation point temperature to 10°C above the transformation point temperature for forging. After cooling down from the furnace, the deformation of the forging is actually carried out in the α + β area. Although this method can obtain a highly plastic α phase network blue structure, the primary α phase of the network blue structure is still within 15%, and The patent specification only mentions in general that the clustered α phase of net blue weaving can be obtained, and does not give a specific metallographic diagram of the net blue structure. The net blue structure obtained by the α+β two-phase titanium alloy produced by this method not ideal organization

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