Develop new carbides for high-performance high-Cr cast irons (HCCIs) with optimized combination of fracture toughness and hardness

开发用于高性能高铬铸铁 (HCCI) 的新型碳化物，具有断裂韧性和硬度的优化组合

• 批准号: 522842-2017
• 负责人: Li, Dongyang
• 金额: $ 5.58万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=691996
• 关键词: Develop; new; carbides; performance; Cr

High Chromium Cast Irons (HCCIs) are widely used in oil sands, mining, and manufacturing industries to resist wear and corrosive wear. The excellent performance of HCCIs results from the combination of hard carbides, e.g., M7C3, and a ferrous matrix. Commercially used HCCIs have their Cr and C contents in the range of 23-30 wt%Cr and 2-3wt%C, respectively. In recent years, the oil sands industry has made great efforts to push Cr and C contents to higher levels with more options for applications under aggressive and harsh conditions. However, raising %C and %Cr increases the material strength but lowers the fracture toughness due to promoted formation of coarse primary carbides, resulting in less impressive performance when encounter wear involving impact force and largely fluctuated wearing forces. Although the performance of HCCIs can be optimized through microstructure engineering, the improvement is limited due to the microstructure inhomogeneity in industrial-scale casting, vague design guidelines, and high costs in manufacturing. Direct modification of carbides in HCCIs is an alternative approach for improved performance and simplified microstructure control. However, relevant research is rather limited due to the limitation of experimental and theoretical tools. The development of multimode atomic force microscope and computational materials science has made the research possible. This project is proposed to tailor carbides in HCCIs with a few promising approaches, including adding 3rd element to carbides, developing complex MC carbides, promoting core-shell structured carbides, and tailoring interfacial bonding between carbides and matrix. The proposed research is based on our successful preliminary studies, and will be conducted in collaboration with our industrial partners in Weir Minerals Canada. Developed knowledge and database will not only benefit the Canadian oil sands industry but also other technical sectors such as mining and manufacturing. Furthermore, the HQPs trained in this project will bring long-term benefits to Canada.

高铬铸铁 (HCCI) 广泛应用于油砂、采矿和制造行业，以抵抗磨损和腐蚀磨损。 HCCI 的优异性能源自硬质碳化物（例如 M7C3）和铁基体的组合。商业使用的HCCI的Cr和C含量分别在23-30wt%Cr和2-3wt%C范围内。近年来，油砂行业努力将 Cr 和 C 含量提高到更高水平，为恶劣和恶劣条件下的应用提供更多选择。然而，提高％C和％Cr会增加材料强度，但会由于促进粗大一次碳化物的形成而降低断裂韧性，导致在遇到涉及冲击力和大幅波动的磨损力的磨损时表现不佳。虽然HCCI的性能可以通过微观结构工程来优化，但由于工业规模铸造中微观结构的不均匀性、模糊的设计准则以及制造成本较高，其改进受到限制。 直接改性 HCCI 中的碳化物是提高性能和简化微观结构控制的另一种方法。然而，由于实验和理论工具的限制，相关研究相当有限。多模式原子力显微镜和计算材料科学的发展使这一研究成为可能。该项目提出通过一些有前景的方法来定制 HCCI 中的碳化物，包括在碳化物中添加第三元素、开发复杂的 MC 碳化物、促进核壳结构碳化物以及定制碳化物和基体之间的界面结合。拟议的研究基于我们成功的初步研究，并将与加拿大韦尔矿业的工业合作伙伴合作进行。发达的知识和数据库不仅有利于加拿大油砂行业，也有利于采矿和制造业等其他技术部门。此外，在该项目中培训的总部人员将为加拿大带来长期利益。