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.

从增加其在汽车领域的使用的角度来看，控制近净形铝合金铸件中的气孔形成至关重要，因为气孔的存在会严重损害承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对许多组件的过度设计的需要也增加了成本，进一步削弱了铸铝产品的商业应用。 铝合金铸件中微孔形成的机制很复杂，因为它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、适合孔成核的位置的存在以及微孔的发展。凝固微观结构。持续需要基础研究来了解这些不同的现象及其对孔隙形成的贡献。下面描述的拟议研究计划将重点关注其中两个现象：1）凝固微观结构受锶基改性影响的作用； 2）表面氧化膜夹带在成核孔中的作用。这两个主题领域都延续了申请人在过去 21 年中对理解和预测铸造过程中缺陷形成的总体研究兴趣。 由此产生的知识以及在工业环境中应用这些知识的工具将为初级金属生产商和近净形状铝产品的制造商带来重大好处。如果成功地应用于商业，这项工作的主要成果将是由于与孔隙形成相关的产品产量损失的减少而降低铸造近终形铝产品的成本。第二个成果将是能够在需要良好疲劳性能的应用中扩大铸造近终形铝产品的使用，从而增加加拿大铸造行业的市场机会。