Interface-based design: A new frontier of alloy development

通过使用集成计算材料工程（ICME）工具来准确预测微观结构（即赋予金属或合金独特性能的“指纹”），可以大大加快轻质材料和产品的新合金的开发。合金元素与迁移界面（晶界和相界面）的相互作用是决定热机械加工过程中微观组织演变的关键方面。然而，缺乏界面的热力学和动力学数据。原子尺度分辨率表征技术和原子建模的最新进展极大地增加了产生新的界面知识的潜力，从而使合金设计方法发生革命性变化。为了开发一种新的基于界面的设计方法，该项目汇集了加拿大领先的计算材料科学家和加拿大电子显微镜中心的实验学家。该方法将被说明为下一代先进的高强度钢，这将是至关重要的轻型车辆设计，以达到加拿大2025年的目标水平，平均车辆的燃油效率（4.4升/100公里）。与传统的汽车钢相比，这些新钢将基于非传统的合金化策略，例如增加Mn（3-10重量%），Si（1-3重量%）和Al（2-6重量%）的含量，这构成了钢铁制造商的范式转变。在这里，贝氏体-铁素体转变起着关键作用，因为它是定制这些钢的性能的关键冶金工具。因此，建议的工作将强调在多组分Fe模型合金和钢中合金元素与铁素体-铁素体界面的相互作用。由加拿大三家主要钢铁生产商（ArcelorMittal Dofasco、美国钢铁加拿大公司、Evraz Inc.）NA）该项目将培养4名博士。学生和两名博士后研究员，他们将获得原子尺度分辨率表征和最先进的计算技术方面的专业知识。拥有这些专业知识的工程师将是加拿大金属生产商和用户保持全球竞争力的关键。

The development of new alloys for lightweight materials and products can be significantly expedited by using integrated computational materials engineering (ICME) tools to accurately predict the microstructures which are the "fingerprints" that give a metal or alloy its unique properties. The interaction of alloying elements with migrating interfaces (grain boundaries and phase-interfaces) is a key aspect that determines microstructure evolution during thermo-mechanical processing. There is, however, a lack of thermodynamic and kinetic data for interfaces. Recent advances in atomic scale resolution characterization techniques and atomistic modelling have dramatically increased the potential to generate new knowledge on interfaces thereby enabling to revolutionize alloy design approaches. To develop a new interface-based design approach this projects brings together a group of Canada's leading computational material scientists with experimentalists at the Canadian Centre for Electron Microscopy. The approach will be illustrated for next generation advanced high-strength steels that will be critical in lightweight vehicle designs to reach the Canadian 2025 target level for fuel efficiency of an average vehicle (4.4 l/100 km). Compared to conventional automotive steels, these new steels will be based on non-traditional alloying strategies with for example increased levels of Mn (3-10 wt%), Si (1-3 wt%) and Al (2-6 wt%), which constitute a paradigm shift for steelmakers. Here, the austenite-ferrite transformation assumes a critical role as it is the key metallurgical tool to tailor the properties of these steels. Thus, the proposed work will emphasize the interaction of alloying elements with the austenite-ferrite interface in multi-component Fe-model alloys and steels. Supported by three leading Canadian steel producers (ArcelorMittal Dofasco, U.S. Steel Canada, Evraz Inc. NA) the project will train four Ph.D. students and two postdoctoral fellows who will gain expertise in atomic scale resolution characterization and state-of-the-art computational techniques. Engineers with this expertise will be essential for Canada's metal producers and users to remain globally competitive.**********