Lee Seulgee, Chokradjaroen Chayanaphat, Sawada Yasuyuki, Yoon Sungmin, Saito Nagahiro
Department of Chemical Systems Engineering, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
Department of International Collaborative Program in Sustainable Materials and Technology for Industries between Nagoya University and Chulalongkorn University, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
Materials (Basel). 2024 Jan 7;17(2):304. doi: 10.3390/ma17020304.
With the goal of developing lightweight Al-Ti-containing multicomponent alloys with excellent mechanical strength, an Al-Ti-Cu-Co alloy with a phase-separated microstructure was prepared. The granulometry of metal particles was reduced using planetary ball milling. The particle size of the metal powders decreased as the ball milling time increased from 5, 7, to 15 h (i.e., 6.6 ± 6.4, 5.1 ± 4.3, and 3.2 ± 2.1 μm, respectively). The reduction in particle size and the dispersion of metal powders promoted enhanced diffusion during the spark plasma sintering process. This led to the micro-phase separation of the (Cu, Co)AlTi (L2) phase, and the formation of a Cu-rich phase with embedded nanoscale Ti-rich (B2) precipitates. The Al-Ti-Cu-Co alloys prepared using powder metallurgy through the spark plasma sintering exhibited different hardnesses of 684, 710, and 791 HV, respectively, while maintaining a relatively low density of 5.8-5.9 g/cm (<6 g/cm). The mechanical properties were improved due to a decrease in particle size achieved through increased ball milling time, leading to a finer grain size. The L2 phase, consisting of (Cu, Co)AlTi, is the site of basic hardness performance, and the Cu-rich phase is the mechanical buffer layer between the L2 and B2 phases. The finer network structure of the Cu-rich phase also suppresses brittle fracture.
为了开发具有优异机械强度的轻质含铝钛多组分合金，制备了一种具有相分离微观结构的铝钛铜钴合金。使用行星式球磨机减小金属颗粒的粒度。随着球磨时间从5小时、7小时增加到15小时，金属粉末的粒径减小（即分别为6.6±6.4、5.1±4.3和3.2±2.1μm）。粒径的减小和金属粉末的分散促进了放电等离子烧结过程中扩散的增强。这导致了（铜，钴）铝钛（L2）相的微相分离，并形成了富含铜的相，其中嵌入了纳米级富含钛的（B2）析出物。通过放电等离子烧结采用粉末冶金制备的铝钛铜钴合金分别表现出684、710和791 HV的不同硬度，同时保持相对较低的密度5.8 - 5.9 g/cm³（<6 g/cm³）。由于通过增加球磨时间实现了粒径减小，从而导致晶粒尺寸更细，机械性能得到改善。由（铜，钴）铝钛组成的L2相是基本硬度性能的所在位置，而富含铜的相是L2相和B2相之间的机械缓冲层。富含铜的相更精细的网络结构也抑制了脆性断裂。
