Hydrogen-based Pore Formation in Aluminum Alloy Castings

铝合金铸件中氢基气孔的形成

• 批准号: 121471-2012
• 负责人: Cockcroft, Steve
• 金额: $ 1.75万
• 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: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=569197
• 关键词: Hydrogen; based; Pore; Formation; Aluminum

The control of pore formation in near-net-shape aluminum alloy castings is critical from the standpoint of increasing their use in the automotive sector as the presence of pores can act to seriously undermine the performance of components subject to cyclic loading. Reduced productivity associated with pore-related defects and the need to over-design many components also adds cost, further eroding increased commercial adoption of cast aluminum products. The mechanism of microporosity formation in aluminum alloy castings is complex, owing to its dependence on the interaction of a number of phenomena occurring during solidification including the decrease in hydrogen solubility, volumetric shrinkage, the presence of suitable sites for pore nucleation and the development of the solidification microstructure. There is an on-going need for fundamental research to understand these various phenomena and their contribution to pore formation. The proposed research program described below will focus on two of these phenomena: 1) the role of the solidification microstructure as influenced by strontium-based modification; and 2) the role of surface oxide film entrainment in nucleating pores. Both subject areas continued the applicants overarching research interest for the past 21 years in understand and predicting defect formation in casting processes. The resulting knowledge and the tools to apply this knowledge in an industrial setting will be of significant benefit to both the primary metal producers and manufactures of near-net-shape aluminum products. The primary outcome of this work, if successfully applied commercially, will be a reduction in the cost-to-cast, near-net-shape, aluminum products stemming from a reduction in product yield loss associated with pore formation. A secondary outcome will be the ability to expand the use of cast, near-net-shape aluminum products in applications that demand good fatigue performance thus increasing market opportunities for the Canadian foundry industry.

从增加其在汽车行业中的使用的角度来看，控制近净形铝合金铸件中的孔隙形成是至关重要的，因为孔隙的存在会严重破坏经受循环载荷的部件的性能。与孔隙相关的缺陷相关的生产率降低以及需要过度设计许多部件也增加了成本，进一步侵蚀了铸铝产品的商业应用。 铝合金铸件中微孔形成的机理是复杂的，这是由于其依赖于凝固过程中发生的许多现象的相互作用，包括氢溶解度的降低、体积收缩、孔形核的合适位置的存在以及凝固组织的发展。有一个持续的基础研究的需要，以了解这些不同的现象和他们的贡献孔形成。下面描述的拟议的研究计划将集中在这些现象中的两个：1）凝固微观结构的作用，影响锶基改性;和2）表面氧化膜夹带成核孔的作用。这两个主题领域延续了申请人在过去21年中在理解和预测铸造过程中缺陷形成方面的总体研究兴趣。 由此产生的知识和在工业环境中应用这些知识的工具将对初级金属生产商和近净形铝产品制造商都有重大利益。这项工作的主要成果，如果成功地应用于商业，将是降低成本，铸造，近净形，铝产品源于减少与孔隙形成相关的产品产量损失。第二个结果将是能够扩大使用铸造，近净形铝产品的应用，需要良好的疲劳性能，从而增加加拿大铸造业的市场机会。