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: 2009
• 资助国家: 加拿大
• 起止时间: 2009-01-01 至 2010-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=435091
• 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.

锆经常被添加到可锻铝合金中以细化晶粒、增加强度并提供更好的抗再结晶能力。然而，Zr的添加可能导致不期望的锆金属间晶体的沉淀，并引起许多与铸造工艺相关的问题和铸造产品中的缺陷。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TiB2晶粒细化的毒害作用对最终产品的性能产生很大的不利影响。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。通过在受控条件下进行热力学计算和物理实验，将研究锆金属间化合物的形成以及锆在典型 7xxx 合金中的溶解度极限。将使用光学金相学以及扫描和透射电子显微镜检查 Zr 含量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。系统研究Zr与其他合金元素（Fe、V、Ti和B）在金属间化合物形成、晶粒细化和抗再结晶方面的相互作用机制。在对典型合金中的锆金属间化合物进行表征后，研究将通过 7xxx 系列合金族来分析复杂的 Zr 轴承金属间化合物的影响并评估所得的材料性能。通过这项研究获得的信息可以极大地帮助铝工业提高许多重要锻造合金的生产率和产品质量。