Inter-American Materials Collaboration: New Steel Microstructures Developed Through Carbon Partitioning

这个美洲材料合作组织汇集了由科罗拉多矿业学院的John Speer和巴西里约热内卢天主教大学的Fernando Rizzo领导的两个小组。该项目研究通过碳分配开发的新型钢组织。这个概念是基于一个新的热力学模型，已经开发来了解马氏体和残余奥氏体之间的碳分配。描述分配终点的模型是新的，并定义了碳在两相中达到均匀化学势的条件，而马氏体/奥氏体界面保持静止（意味着铁原子完全不动）。一些重要的潜在应用，这一新的概念被确定，沿着与贝氏体转变的机制有关的基本影响。美国学生参与者的教育是丰富的，通过与巴西学术界和工业界的互动。 学生通常受益于与这项工作相关的研究，出版和外部互动，并在学术或工业研究环境中接受就业教育。该项目预计将导致重要的发展，将被纳入参与大学和其他地方的物理冶金课程，并应提供的结果，可以导致新的合金化/加工方法，可用于各种重要的钢铁应用。 与PUC-Rio的合作使美国调查人员能够与巴西最受尊敬的物理冶金集团之一保持关系，该集团位于该国最大的钢铁生产商附近。 该奖项得到了材料研究部、国际科学与工程办公室以及数学和物理科学理事会多学科活动办公室的支持。

This Inter-American Materials Collaboration brings together two groups led by John Speer at the Colorado School of Mines and Fernando Rizzo at the Pontificia Universidade Catolica in Rio de Janeiro, Brazil. The project investigates novel steel microstructures developed through carbon partitioning. The concept is based on a new thermodynamic model that has been developed to understand carbon partitioning between martensite and retained austenite. The model to describe the endpoint of partitioning is new, and defines the conditions under which carbon reaches a uniform chemical potential in the two phases, while the martensite/austenite interface remains stationary (implying complete immobility of iron atoms). A number of important potential applications for this new concept are identified, along with fundamental implications related to the mechanism of bainite transformation in steels.The education of US student participants is enriched through the interactions with academia and industry in Brazil. Students benefit generally from the research, publishing, and external interactions associated with this work, and are educated for employment in an academic or industrial research setting. The project is expected to lead to important developments that will be incorporated into physical metallurgy curricula at the participating universities and elsewhere, and should provide results that can lead to novel alloying/processing approaches that can be employed for a variety of important steel applications. Collaboration with PUC-Rio allows the US investigators to maintain a relationship with one of the highest regarded physical metallurgy groups in Brazil, which is located nearby to the largest steel producer in that country. This award is supported by the Division of Materials Research, the Office of International Science and Engineering, and the Office of Multidisciplinary Activities in the Directorate for Mathematical and Physical Sciences.