Wang Ying, Xu Huanqing, Chen Yulan, Qi Xiaoben, Zhong Ning
School of Materials Science, Shanghai Dianji University, Shanghai 201306, China.
College of Ocean Science and Engineering, Shanghai Maritime University, Shanghai 201306, China.
Nanomaterials (Basel). 2024 Dec 12;14(24):1990. doi: 10.3390/nano14241990.
In this work, the Al-Mo nanocrystalline alloy films with Mo contents ranging from 0-10.5 at.% were prepared via magnetron co-sputtering technology. The composition and microstructure of alloy thin films were studied using XRD, TEM, and EDS. The mechanical behaviors were tested through nanoindentation. The weights of each strengthening factor were calculated and the strengthening mechanism of alloy thin films was revealed. The results indicate that a portion of Mo atoms exist in the Al lattice, forming a solid solution of Mo in Al. The other part of Mo atoms tends to segregate at the grain boundaries, and this segregation becomes more pronounced with an increase in Mo content. There are no compounds or second phases present in any alloy films. As the Mo element content increases, the grain size of the alloy films gradually decreases. The hardness of pure aluminum film is 2.2 GPa. The hardness increases with an increase in Mo content. When the Mo content is 10.5 at.%, The hardness of the film increases to a maximum value of 4.9 GPa. The fine grain (∆Hgb), solid solution (∆Hss), and nanocrystalline solute pinning (∆Hnc,ss) are the three main reasons for the increase in the hardness of alloy thin films. The contribution of ∆Hgb is the largest, accounting for over 60% of the total, while the contribution of ∆Hss accounts for about 30%, ranking second. The rest of the increase is due to ∆Hnc,ss.
在本工作中，通过磁控共溅射技术制备了Mo含量范围为0 - 10.5 at.%的Al-Mo纳米晶合金薄膜。利用X射线衍射（XRD）、透射电子显微镜（TEM）和能谱仪（EDS）研究了合金薄膜的成分和微观结构。通过纳米压痕测试了其力学行为。计算了各强化因素的权重，揭示了合金薄膜的强化机制。结果表明，一部分Mo原子存在于Al晶格中，形成Mo在Al中的固溶体。另一部分Mo原子倾向于在晶界处偏聚，且随着Mo含量的增加，这种偏聚变得更加明显。所有合金薄膜中均不存在化合物或第二相。随着Mo元素含量的增加，合金薄膜的晶粒尺寸逐渐减小。纯铝薄膜的硬度为2.2 GPa。硬度随Mo含量的增加而增大。当Mo含量为10.5 at.%时，薄膜硬度增加到最大值4.9 GPa。细晶强化（∆Hgb）、固溶强化（∆Hss）和纳米晶溶质钉扎强化（∆Hnc,ss）是合金薄膜硬度增加的三个主要原因。∆Hgb的贡献最大，占总量的60%以上，而∆Hss的贡献约为30%，排名第二。其余的硬度增加归因于∆Hnc,ss。
