Characteristics of ZrAl intermetallic crystals during solidification of aluminum wrought alloys

锻铝合金凝固过程中ZrAl金属间化合物晶体的特性

• 批准号: 372063-2009
• 负责人: Chen, Grant
• 金额: $ 1.68万
• 依托单位: Université du Québec à Chicoutimi
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2010
• 资助国家: 加拿大
• 起止时间: 2010-01-01 至 2011-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=461505
• 关键词: Characteristics; ZrAl; intermetallic; crystals; during

Zirconium is often added in aluminum wrought alloys to refine the grains, increase the strength and provide a better resistance to recrystallization. However, the addition of Zr may lead to the precipitation of undesirable zirconium intermetallic crystals and cause a number of casting process related problems and defects in the cast products. It is observed in some cases that interaction of Zr with other alloying elements (Fe, V, Ti and B) and poisoning effect of Zr on the Ti and TiB2 grain refinement have a great detrimental effect on the properties of final products. The main objective of this study is to better understand the effect of zirconium and its intermetallics on the fabrication processes and final product properties. Using thermodynamic calculation and physical experiments under controlled conditions, the formation of zirconium intermetallics and the solubility limit of zirconium in a typical 7xxx alloy will be investigated. The impact of the Zr level and the cooling condition on the nucleation, growth and morphology of zirconium intermetallic crystals will be examined using optical metallography and scanning and transmission electron microscopes. The mechanisms of the interaction of Zr with other alloying elements (Fe, V, Ti and B) in term of intermetallic formation, grain refinement and anti-recrystallization will be systematically studied. After the characterization of zirconium intermetallics in a typical alloy, the research will go through the 7xxx series alloy family to analyze the impact of complex Zr bearing intermetallics and to evaluate the resulted material properties. The information gained through this study can greatly help the aluminum industry to enhance the productivity and product quality for a number of important wrought alloys.

锆通常被添加到铝锻造合金中以细化晶粒，增加强度并提供更好的抗再结晶性。然而，Zr的添加可能导致不期望的锆金属间化合物晶体的沉淀，并在铸造产品中引起许多铸造工艺相关的问题和缺陷。在某些情况下，观察到Zr与其他合金元素（Fe、V、Ti和B）的相互作用以及Zr对Ti和TiB 2晶粒细化的毒化效应对最终产品的性能有很大的不利影响。本研究的主要目的是更好地了解锆及其金属间化合物对制造工艺和最终产品性能的影响。通过热力学计算和控制条件下的物理实验，将研究锆金属间化合物的形成和锆在典型7xxx合金中的溶解极限。Zr水平和冷却条件对锆金属间化合物晶体的成核、生长和形态的影响将使用光学金相、扫描和透射电子显微镜进行检查。从金属间化合物的形成、晶粒细化和抗再结晶等方面系统地研究了Zr与其他合金元素（Fe、V、Ti和B）的相互作用机制。在典型合金中锆金属间化合物的表征之后，研究将通过7xxx系列合金族来分析复杂Zr轴承金属间化合物的影响并评估所得材料性能。通过本研究获得的信息可以大大帮助铝工业提高生产率和产品质量的一些重要的变形合金。