Design and Development of Fire-Resistant Ferritic Steels for Structural Applications

结构用耐火铁素体钢的设计和开发

• 批准号: 1130000
• 负责人: Semyon Vaynman
• 金额: $ 29.99万
• 依托单位: Northwestern University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1130000&HistoricalAwards=false
• 关键词: Design; Development; Fire; Resistant; Ferritic

The research is to integrate two novel scientific concepts in the design and fabrication of fire-resistant steels. First, instead of carbon, nanosized coherent copper precipitates will be used for primary strengthening. The low carbon content makes the steel readily weldable without pre- or post-heat treatment. Coherent precipitates tend to coarsen slower with increasing temperature, resulting in less strength degradation at higher temperatures. Second, either Nb or Ti will be used as an alloying element to delay the transition to the high-temperature regime in which rapid grain growth, precipitate coarsening, and dislocation recovery may occur, and to promote secondary strengthening by the formation of metal carbide precipitates. The research provides the intellectual basis for designing stronger fire-resistant steels that meet tougher standards, with results that are readily portable to other high-temperature applications such as boilers, turbines and powertrains for enhanced efficiency. Further, this research addresses nanoscale structure-property relationships in ferrous alloys that are often considered to be mature and old-fashioned, an erroneous impression that permeates throughout the community. Outreach activities conducted by the principal investigators will represent the first step to addressing this fallacy, resulting in students who can think about nanotechnology in broader terms, in industrial scientists and engineers who are better informed about modern advances in metallurgy, and in government agencies willing to take a lead in technology developments. With millions of tons of steels being used in buildings, highways, and bridges every year, many opportunities await the development of inexpensive, easily produced, high-performance steels.

该研究是在耐火钢的设计和制造中整合两个新的科学概念。 首先，纳米尺寸的共格铜沉淀物将代替碳用于初级强化。 低碳含量使钢易于焊接，无需预处理或后热处理。 共格沉淀物倾向于随温度升高而变粗，导致在较高温度下强度降低较少。 第二，Nb或Ti将被用作合金元素以延迟向高温状态的转变，在高温状态中可能发生快速晶粒生长、沉淀物粗化和位错恢复，并且通过形成金属碳化物沉淀物来促进二次强化。该研究为设计符合更严格标准的更坚固的耐火钢提供了知识基础，其结果可随时移植到其他高温应用中，如锅炉，涡轮机和动力系统，以提高效率。 此外，这项研究解决了通常被认为是成熟和老式的铁合金中的纳米级结构-性能关系，这是一种渗透在整个社区的错误印象。 由主要研究人员进行的推广活动将是解决这一谬误的第一步，使学生能够从更广泛的角度思考纳米技术，使工业科学家和工程师更好地了解冶金学的现代进步，并使政府机构愿意在技术发展方面发挥带头作用。 每年有数百万吨的钢材用于建筑、公路和桥梁，因此有许多机会等待开发廉价、易于生产的高性能钢材。