Developing a high-strength Al-Mg-Si-Sc-Zr alloy for selective laser melting: Crack-inhibiting and multiple strengthening mechanisms
Developing a high-strength Al-Mg-Si-Sc-Zr alloy for selective laser melting: Crack-inhibiting and multiple strengthening mechanisms
复制标题
开发用于选择性激光熔化的高强度 Al-Mg-Si-Sc-Zr 合金：裂纹抑制和多重强化机制
DOI：
10.1016/j.actamat.2020.03.060
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发表时间：
2020-07-01
期刊：
影响因子：
9.4
通讯作者：
Zhu, Hongbin
中科院分区：
文献类型：
--
作者：
Li, Ruidi;Wang, Minbo;Zhu, Hongbin
为了开发用于选择性激光熔化（SLM）增材制造的高强度铝合金，我们设计了一系列Al-Mg（-Si）-Sc-Zr合金，并使用雾化合金粉末对其进行增材制造。在不含Si的情况下，所开发的Al-xMg-0.2Sc-0.1Zr（x = 1.5，3.0和6.0wt%）合金都容易发生热裂纹，并且平均裂纹密度随着Mg含量的增加而增加。Al-6 Mg-0.2Sc-0.1Zr合金中添加1.3wt%的Si有效地抑制了SLM过程中的热裂纹，同时细化了显微组织，从而导致印刷样品中的机械性能增强。通过对合金成分的进一步微调，设计了Al-8.0Mg-1.3Si-0.5Mn-0.5Sc-0.3Zr合金。这种新合金显示出显著细化的显微组织，其由亚微米胞和存在于胞中的共格Al-3（Sc，Zr）纳米颗粒（2-15 nm）和晶间Al-Mg 2Si共晶（Mg 2Si直径10-100 nm）组成。高密度的堆垛层错和独特的9 R相形成在印刷样品中。印刷态样品的抗拉强度和伸长率分别达到497 MPa和11%。在时效处理后，抗拉强度达到550 MPa，而塑性范围为8%至17%，这取决于时效条件。除了固溶强化、晶界强化和纳米颗粒强化外，高密度层错也对强化有贡献。(C)2020 Acta Materialia Inc.由爱思唯尔有限公司出版。保留所有权利。
To develop high-strength Al alloys for selective laser melting (SLM) additive manufacturing, we designed a series of Al-Mg(-Si)-Sc-Zr alloys and additively manufactured them using atomized alloy powders. In the absence of Si, the developed Al-xMg-0.2Sc-0.1Zr (x = 1.5, 3.0 and 6.0 wt%) alloys are all susceptible to hot cracking and the average crack density increases with increasing Mg content. The addition of 1.3 wt% Si into the Al-6Mg-0.2Sc-0.1Zr alloys effectively inhibits hot cracking during SLM and simultaneously refines the microstructure, and thus leading to enhanced mechanical properties in the as-printed samples. By further fine-tuning the alloy compositions, we designed a new alloy Al-8.0Mg-1.3Si-0.5Mn-0.5Sc-0.3Zr. This new alloy demonstrates significantly refined microstructure consisting of submicron cells with coherent Al-3(Sc, Zr) nano-particle (2-15 nm) residing in the cell and intergranular Al-Mg2Si eutectic (Mg2Si diameter 10-100 nm). High-density stacking faults and a unique 9R phase are formed in the as-printed sample. The tensile strength and elongation of the as-printed sample are up to 497 MPa and 11%, respectively. After the aging treatment, the tensile strength reaches 550 MPa, while the ductility ranges from 8% to 17%, depending on the aging conditions. In addition to solid solution strengthening, grain boundary strengthening and nanoparticle strengthening, the high-density stacking faults also contributes to strengthening. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.