Phenomenological studies on solidification and casting of aluminum and magnesium alloys

铝镁合金凝固铸造唯象研究

• 批准号: RGPIN-2014-04852
• 负责人: Ravindran, Comondore
• 金额: $ 1.46万
• 依托单位: Ryerson University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=663052
• 关键词: Phenomenological; studies; solidification; casting; aluminum

Weight reduction, enhanced fuel efficiency (2025 CAFE: 65.4 MPG), energy conservation, reduced carbon emissions and recycling have become cornerstones for a prosperous global economy and high quality of life. Light alloys of aluminum (density: 2.70 g/cm3) and magnesium (density: 1.74 g/cm3) hold much hope, and provide scope for the development of novel manufacturing processes for the automotive sector. However, there are still some challenges impeding the increased use of these alloys, because they are particularly prone to forming casting defects (e.g., inclusions, porosity, hot tearing, misruns, distortion) during solidification. There is also a need to improve the high temperature performance of aluminum alloys used in engine systems (e.g., engine blocks, cylinder heads) with improved operating efficiency. For magnesium alloys, specific needs include the development of new grain refiners for enhanced strength and castability.**This research program seeks to build upon extensive research experience, knowledge and success in castability and characterization of aluminum and magnesium alloys. It envisages a deeper understanding of solidification mechanisms, with a view to reducing the formation of casting defects and improving the mechanical properties of aluminum and magnesium alloys.**A new methodology, based on neutron diffraction analysis, will be used to characterize the formation of defects in aluminum and magnesium alloys, specifically for relating the microstructure, strain/stress and hot tear formation. In-situ and ex-situ neutron diffraction will be used for dynamic monitoring of solid fractions of phases and for residual strain/stress mapping. Commercial software will be utilized for modeling heat transfer, hot spots, heat flow, fluid flow and hot tearing in conjunction with neutron analyses and microstructural characterization. The fundamental knowledge gained from both the modeling and the laboratory experiments will be used to explain and predict the formation of casting defects with a view to transferring the knowledge on an industrial scale for foundry and in-service automotive applications. For aluminum alloys, a systematic study relating solidification conditions, heat treatment procedures, mechanical properties and residual strain/stress will be carried out, with a view to eliminating distortions in castings. Novel magnesium grain refiners will be synthesized with appropriate ball milling and sintering for the development of high performance castings. The program will reinforce and enhance an excellent track record of HQP training.**The impact of this research will be felt in the 3Es: Energy, environment and economy. Elimination of fuel leakage, increased operating efficiency and extension to new technologies (e.g. linerless engine blocks) will result in increased lightweighting, directly impacting conservation of energy and reducing greenhouse gas emissions. Overall, these advances will reduce recalls (via elimination of distortion) and significantly decreased scrap rate of castings (thru elimination of hot tearing) ensuring enhanced profitability for the Canadian automotive industry, contributing to the revival of the auto economy. As a consequence, they will significantly help in developing standards, policies and overall vision for automobile weights and related emission levels.

减轻重量、提高燃油效率（2025年CAFE：65.4 MPG）、节能、减少碳排放和回收利用已成为全球经济繁荣和高质量生活的基石。铝（密度：2.70 g/cm 3）和镁（密度：1.74 g/cm 3）的轻合金具有很大的希望，并为汽车行业开发新的制造工艺提供了空间。然而，仍然存在一些阻碍这些合金的增加使用的挑战，因为它们特别容易形成铸造缺陷（例如，夹杂物、孔隙、热裂、浇不足、变形）。还需要改进用于发动机系统的铝合金的高温性能（例如，发动机缸体、气缸盖），提高了工作效率。对于镁合金，具体需求包括开发新的晶粒细化剂，以提高强度和可铸性。**该研究计划旨在建立在广泛的研究经验，知识和铝和镁合金的可铸性和表征的成功。它设想更深入地了解凝固机制，以减少铸造缺陷的形成并提高铝和镁合金的机械性能。一种新的方法，基于中子衍射分析，将用于表征铝和镁合金中缺陷的形成，特别是与微观结构，应变/应力和热裂形成。原位和非原位中子衍射将用于动态监测相的固体分数和残余应变/应力绘图。商业软件将用于模拟热传递，热点，热流，流体流动和热撕裂结合中子分析和微观结构表征。从建模和实验室实验中获得的基础知识将用于解释和预测铸造缺陷的形成，以期在铸造和在役汽车应用的工业规模上转移知识。对于铝合金，将进行有关凝固条件、热处理程序、机械性能和残余应变/应力的系统研究，以消除铸件中的变形。通过适当的球磨和烧结，可以合成新型镁晶粒细化剂，用于高性能铸件的开发。该计划将巩固和提高HQP培训的良好记录。**这项研究的影响将体现在3E：能源，环境和经济。消除燃油泄漏、提高运行效率和推广新技术（如无衬套发动机组）将导致轻量化，直接影响能源节约和减少温室气体排放。总的来说，这些进步将减少召回（通过消除变形），并显着降低铸件的报废率（通过消除热裂），确保提高加拿大汽车行业的盈利能力，促进汽车经济的复苏。因此，它们将大大有助于制定汽车重量和相关排放水平的标准、政策和总体设想。