TC11 titanium alloy is an α + β type heat-resistant titanium alloy, mainly used in the manufacture of aircraft compressor disks, blades and other parts. It is the main titanium alloy material for domestic aeroengines and has been widely used in rotating parts of rocket engines. With the wide application of this alloy, the requirements of its various technical indicators are becoming more and more strict.
In the deformation semi-finished products of titanium alloys, especially in the deformation semi-finished products of two-phase titanium alloys, the alloy composition, the original structure of the billet, the heating system, the deformation rate, the deformation uniformity and the temperature conditions of deformation are the basic factors affecting the final macrostructure of the bar Factors, and different organizations can significantly change the mechanical properties of semi-finished products. Researchers use forging and rolling equipment to produce TC11 titanium alloy rods with specifications of Φ73mm and Φ29mm, and study the effects of different thermal processing techniques on their organization and performance.
The material used in the experiment was the three vacuum consumable arc melting ingots produced by a company. The similar process was performed. The billet forging and forging were provided with a hot-rolled billet of Φ150mm and a blank forging machine of Φ125mm forging machine. Observed 100 times, the morphology of the tissues are relatively thick and isometric and uniform.
The above-mentioned blanks were produced on precision forging machines and hot continuous rolling equipment with TC11 titanium alloy rods of Φ73mm and Φ29mm, the heating temperature was 970 ℃, and the deformation rate was 2.5m / s.
Precision forging process: the precision forging machine is used to perform four deformations in one fire, the total deformation is 65.9%, the average reduction is 13mm, and Φ73 mm TC11 titanium alloy forged bars are produced. The precision forging machine equipment is used to deform 9 times of three fires, the average deformation of single fire is 61.1%, the average reduction is 8mm, and the Φ29mm TC11 titanium alloy forged bar is produced.
Rolling process: hot continuous rolling equipment is used for one pass 9 times of deformation, the total deformation is 76.3%, the average reduction is 35mm, and Φ73mmTC11 titanium alloy rolled bar is produced. The hot continuous rolling equipment was used to perform the 15-pass deformation in two fires. The average deformation in a single fire was 80.3% and the average reduction was 29mm. Φ29mm TC11 titanium alloy rolled bar was produced.
The samples were annealed at 950 ℃ / 1h · AC + 530 ℃ / 6h · AC to test the structure and performance of the finished bars of different processes. The results showed that:
- The TC11 specifications produced by the precision forging process are finished products of Φ73mm and Φ29mm bars. The microstructure is smaller than that of the bars produced by the hot continuous rolling process, and the uniformity is good.
- At the same heating temperature, the mechanical properties of the TC11 titanium alloy bar produced by the precision forging process are superior to the rolled bar, which is suitable for the production of blade bars with high organization and performance requirements; compared with the precision forging production method The new hot continuous rolling process has high production efficiency, good product flatness and surface quality, and can save finished products.