Development of the next generation high strength Mg alloys for the automotive industry

开发用于汽车行业的下一代高强度镁合金

• 批准号: RGPIN-2016-05261
• 负责人: Bichler, Lukas
• 金额: $ 2.4万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 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=684654
• 关键词: Development; next; generation; strength; Mg

For decades, technological advancements have been driven by the progress in materials science. For example, the substitution of iron components in automobiles with lighter aluminum components during the 1970's and 80's resulted in an immediate performance and fuel economy enhancement. Recently, the Environmental Protection Agency and the Dept. of Transportation in USA mandated automakers to decrease greenhouse gas emissions and improve fuel economy by over 50% by 2025, otherwise face economic penalties. It is generally accepted that such a drastic improvement is achievable either by vehicle hybridization, or by vehicle weight reduction. Both approaches face challenges: 1) Hybridization is costly and adds weight to vehicles, and 2) Existing manufacturing processes for lightweight alloys are approaching technological limits and further advancements are costly. *** *In this Discovery program, we will explore an innovative multi-process approach to overcome the limits associated with existing manufacturing methods for ultralight high-strength magnesium (Mg) alloys. Specifically, an advanced powder metallurgy process (Spark Plasma Sintering, SPS) will be combined with a traditional metalcasting process to develop castable Mg alloys with tensile properties and ductility comparable to wrought Mg alloys. Using SPS, nano- and micro-scale ceramic reinforcements will be blended and sintered into a Mg powder matrix to form “Dual-Phase Advanced Ceramic Modifier” (DP-ACM) discs. The sintered DP-ACM discs will be subsequently added to liquid Mg alloys during casting, resulting in dissolution of the Mg matrix of the DP-ACM within the melt, followed by a homogeneous release of the ceramic reinforcements in the melt. The reinforcements will serve to simultaneously enhance the room temperature strength and ductility (via grain refinement and the modification of eutectics) and creep resistance (via grain boundary pinning). This novel approach is anticipated to overcome several critical challenges (e.g., particle settling, flotation or oxidation) associated with current treatment methods for liquid Mg alloys.*** *In addition to fabricating the DP-ACMs for the treatment of liquid Mg alloys, our group will also investigate the effect of SPS process parameters on the sinterability of metallic and ceramic materials. Specifically, our work will focus on the presently unknown effect of the electric current and powder morphology on the fusion of powder particles during SPS processing. The generated knowledge will enable sintering of materials with precisely controlled microstructure and properties. *** *Experimental work in both areas will be carried out at my UBC laboratories and will provide HQPs hands-on and fundamental knowledge in the fields of manufacturing and materials science. This program will provide a foundation for a novel approach to develop castable high-strength Mg alloys. **

几十年来，材料科学的进步推动了技术的进步。例如，在20世纪70年代和80年代，用较轻的铝部件代替汽车中的铁部件，立即提高了汽车的性能和燃油经济性。最近，美国环境保护署和运输部要求汽车制造商到2025年减少温室气体排放，并将燃油经济性提高50%以上，否则将面临经济处罚。人们普遍认为，这种巨大的改进可以通过车辆混合或车辆减重来实现。这两种方法都面临着挑战：1)杂交技术成本高，而且会增加车辆的重量；2)现有的轻质合金制造工艺正接近技术极限，进一步发展成本高昂。*** *在这个探索项目中，我们将探索一种创新的多工艺方法，以克服现有超轻高强度镁（Mg）合金制造方法的局限性。具体来说，先进的粉末冶金工艺（火花等离子烧结，SPS）将与传统的金属铸造工艺相结合，以开发具有拉伸性能和延展性可与变形镁合金相媲美的可浇注镁合金。利用SPS，纳米级和微级陶瓷增强剂将混合并烧结成Mg粉末基体，形成“双相高级陶瓷改性剂”（DP-ACM）圆盘。烧结后的DP-ACM圆盘随后将在铸造过程中添加到液态镁合金中，导致DP-ACM的Mg基体在熔体中溶解，随后熔体中的陶瓷增强物均匀释放。增强材料可以同时提高室温强度和塑性（通过晶粒细化和共晶改性）以及抗蠕变（通过晶界钉住）。这种新方法有望克服与当前液态镁合金处理方法相关的几个关键挑战（例如，颗粒沉降、浮选或氧化）。*** *除了制造用于处理液态镁合金的DP-ACMs外，我们的团队还将研究SPS工艺参数对金属和陶瓷材料烧结性能的影响。具体来说，我们的工作将集中在目前未知的电流和粉末形态在SPS加工过程中对粉末颗粒融合的影响。所产生的知识将使烧结材料具有精确控制的微观结构和性能。*** *这两个领域的实验工作将在我的UBC实验室进行，并将为HQPs提供制造和材料科学领域的实践和基础知识。该项目将为开发可浇注高强度镁合金的新方法奠定基础。**