【作者】 余敏；

【导师】 罗迎社；

【作者基本信息】 湘潭大学 ， 一般力学与力学基础， 2006， 硕士

【摘要】 流变成形理论是近年来在塑性成形原理、超塑性成形理论、蠕变成形理论的基础上发展起来的、更富普遍性意义的一种成形理论,是流变学在塑性加工领域的具体应用。该理论正在越来越广泛地为人们所认可和接受,并不断地应用到科学研究和生产实践中去,逐步地显示出它的强大生命力和应用前景.TC11钛合金作为一种新型的航空和宇航材料,具有比强度高、抗疲劳、耐腐蚀等突出优点,主要用于制造飞机上的重要零部件,如涡轮发动机的压气机盘、叶片盘和单个的叶片等等。因此,对其热流变成形进行研究具有重要意义。本文首先简要介绍了数值模拟技术在金属成形领域中的研究现状,以及刚(粘)塑性有限元法的基本原理及其在体积成形软件DEFORM　3D的具体体现。其次,通过UG对成形模具和坯料造型,并在DEFORM　3D平台上对第二级TC11钛合金叶片盘的热流变成形过程进行了数值模拟,对成形过程等效应力场、等效应变场、温度场以及变形抗力曲线进行了分析。由于TC11钛合金对成形温度和变形速率非常敏感,而它的成形温度范围很窄,受到加热规范的制约,因此我们比较了成形温度一定、不同变形速率对模拟结果的影响,揭示了流变成形的金属流动规律,预测和分析了可能出现的叶型局部未充满的现象。对工艺和模具设计具有一定的理论指导意义和实际应用价值,为流变成形的逆向设计提供了可能性。数值模拟的有关结果不但与实际产品吻合较好,而且证明了有关理论的正确性。最后参考利用数值模拟的结果进行了试生产,并对试生产产品进行了机械性能检测和金相组织分析,结果表明:用流变成形方法生产的产品,与传统生产方法生产的产品相比,内部组织得到了较大改善,机械性能有了较大幅度的提高。更多还原

【Abstract】 The theory of rheological forming, a deformation theory of greater universal significance, has been developed recent years based on the theories of plastic forming, super-plastic forming and creep forming. It is the practical application of rheology to plastic working field. The theory is being widely accepted and applied for scientific research as well as production practice, and is showing its strong vitality and practical prospect.As a new aeronautic material, TC11 titanium alloy has many prominent merits, such as high intensity, fatigue resistance, corrosion resistance, etc.. It is mainly used for manufacturing the important parts and components of aeroplanes, like compressor disks of turbine engine, vane disks and single vane, etc.. Therefore, to research on the rheological forming of TC11 titanium alloy is significant.Firstly, the current status of the researching on numerical simulation technology in the field of metal forming has been introduced in this paper, and the basic principle of rigid-plastic(visco-plastic)finite element method and its embodiment in bulk forming software of DEFORM 3D has also been introduced.Next, the forming dies and billet have been modeled by UG, and the numerical simulation of the hot rheological forming of the secondary titanium alloy vane disk have been conducted based on DEFORM 3D platform. All the results of numerical simulation, which include the numerical simulation of equivalent strain field, equivalent stress field and temperature distribution, etc., have been analyzed. TC11 titanium is sensitive to forming temperature and strain rate, however, the range of forming temperature is narrow and is bound by heating norm, so the influence of the same forming temperature and various strain rates on the simulation results is compared. Then the metal’s flowing law of rheological forming is revealed and the possible underfilled phenomenon is also predicted and analyzed, which possesses certain theoretic guidance and application worthiness to the design of technology and dies, therefore, the converse design of rheological forming become conceivable. The numerical simulation results not only accord with practical producing, but更多还原