复杂结构钛合金机翼的等温锻造试验研究

Experimental Study on Isothermal Forging Technology for a Complex-Shaped Titanium Alloy Wing

摘要:

Ti-6Al-4V合金是应用于航空和汽车工业领域的关键结构件,但是它硬度高,难加工,价格昂贵,且大尺寸毛坯时材料利用率很低,采用传统加工方法很难满足现代制造的需求。本文针对Ti-6Al-4V机翼,采用铅模拟实验优化了合理的锻坯形状,并引入了一种闭式等温锻造工艺,研究了等温锻造Ti-6Al-4V机翼的成形能力、机械性能和工艺参数等性能。结果表明：与传统加工的钛合金机翼相比,等温锻造机翼显著的改善了零件的机械性能,材料利用率从13%提高到50%；在950℃的等温锻造温度下,Ti-6Al-4V基体内片状α相逐渐转变为β相,而当锻造温度为900℃时,这种相变效果呈减弱趋势。

Abstract:

The complex-shaped Ti-6Al-4V alloy is widely used in the aerospace engineering and automobile industry. However, because of its high hardness, easy adhesion, large dimension and high precision, it is a great deal of cost of raw materials, and besides, it is difficult to machine unless it uses special cutting tools by the traditional manufacturing methods. In this study, a closed isothermal forging process was adopted for precision forming of the wing. The rational billet shapes were estimated by flow simulation experiment, and then mechanical property, forming ability, process parameters of the Ti-6Al-4V wing were studied by the isothermal forging tests to meet performance targets. The results show that, compared with the titanium wing formed by conventional methods, the wing made by isothermal forging remarkably improved mechanical performances, and material utilization was reaching from 13% to 50%. During the isothermal forging process of Ti-6Al-4V, the flake α grains at 950℃ was transformed to β grains in the matrix; while the progress of transformation diminished when the forging temperature decreased to 900℃.