Effect of Alloying and Thermo-Mechanical-Treatment on Anisotropic Creep and Deformation of Ti-alloys

合金化和形变热处理对钛合金各向异性蠕变和变形的影响

• 批准号: 0101309
• 负责人: K. Linga Murty
• 金额: $ 36.23万
• 依托单位: North Carolina State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-01 至 2006-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0101309&HistoricalAwards=false
• 关键词: Effect; Alloying; Thermo; Mechanical; Treatment

This project addresses the influence of thermo-mechanical-treatment (TMT) and alloying on deformation and creep anisotropy of titanium alloys. The research involves characterization of anisotropic biaxial creep of Ti alloys using closed-end internally pressurized thin-walled tubing superimposed with an axial load. The approach is to investigate these behaviors in Ti and Ti- 3Al-2.5V following stress-relief anneal and complete recrystallization. Alloying additions such as Al to Ti result in significant modification of crystallographic texture and operating slip systems. Cold-working leads to grain-shape anisotropy of the otherwise equiaxed grain structure of Rx materials. The effects of these variables on deformation microstructures are to be investigated along with deformation anisotropy following biaxial loading under varied stress-states and stress-levels. Transitions in creep mechanisms and the effect of underlying deformation mechanism(s) on creep anisotropy will also be addressed. Such studies are important for realistic estimates of creep strains and life of these structural materials in service.%%% The project addresses basic research issues in a contemporary topical area of materials science with technological relevance in aerospace, automobile, and chemical sectors where Ti-alloys are used in tube form. An important feature of the program is the integration of research and education through the training of students in a fundamentally and technologically significant area. The project is expected to provide unique opportunities for graduate and undergraduate students to develop strong technical, communication, and organizational/management skills through experiences in a forefront research environment. ***

该项目研究了热机械处理（TMT）和合金化对钛合金变形和蠕变各向异性的影响。该研究涉及使用叠加轴向载荷的封闭端内部加压薄壁管来表征钛合金的各向异性双轴蠕变。该方法是研究 Ti 和 Ti-3Al-2.5V 在去应力退火和完全再结晶后的这些行为。添加合金元素（例如将 Al 添加到 Ti 中）会显着改变晶体结构和工作滑移系统。冷加工会导致 Rx 材料的等轴晶粒结构出现晶粒形状各向异性。将研究这些变量对变形微观结构的影响以及在不同应力状态和应力水平下双轴加载后的变形各向异性。还将讨论蠕变机制的转变以及潜在变形机制对蠕变各向异性的影响。此类研究对于实际估计这些结构材料在使用中的蠕变应变和寿命非常重要。%%% 该项目解决了当代材料科学主题领域的基础研究问题，与航空航天、汽车和化学领域的技术相关，其中 Ti-合金以管状形式使用。该计划的一个重要特点是通过在基础和技术重要领域对学生进行培训，将研究和教育结合起来。该项目预计将为研究生和本科生提供独特的机会，通过前沿研究环境中的经验来培养强大的技术、沟通和组织/管理技能。 ***