TY - JOUR
T1 - Excellent thermal stability of nanostructured Al2O3–Y3Al5O12–ZrO2 eutectic ceramic composites by high-speed directional solidification
AU - Zhao, Di
AU - Su, Haijun
AU - Hao, Shuqi
AU - Shen, Zhonglin
AU - Liu, Yuan
AU - Guo, Yinuo
AU - Yang, Peixin
AU - Zhang, Zhuo
AU - Guo, Min
N1 - Publisher Copyright:
© 2023 Elsevier Ltd
PY - 2023/11
Y1 - 2023/11
N2 - The contradiction between the nanostructure and thermal stability is the major obstacle on the way of the practical applications of nanomaterials. Here we demonstrated a simple solution for reconciling this contradiction, i.e., the high-speed directional solidification of a ternary eutectic ceramic composite. Its highly textured lamellar and rod-like nanostructures and low-energy interfaces contributed to an outstanding thermal stability that the nanostructure was maintained after being heated at 1573 K for 100 h. It was uncovered that the high solidification rate of 1080 mm/h had an evident restriction on the growth orientation of the faceted crystals during the solidification process, forming a highly textured nanostructure. Combining with the interface energy minimization mechanism, the low-energy interfaces were simultaneously obtained. The evolution of microstructure and interface characteristics during the coarsening process at the higher temperature was further studied. The lamellar structure presented a better thermal stability than that of the rod-like structure since the former had a constraint on the diffusion dimensions. Moreover, a novel structural evolution pattern in the coarsening process was revealed, which was completely different from that of traditional sintered ceramics. The solidified specimens could further keep stable in density, homogeneity of structure and size of internal pores during heat treatment, contributing to a better stability in hardness than that of traditional sintered specimens.
AB - The contradiction between the nanostructure and thermal stability is the major obstacle on the way of the practical applications of nanomaterials. Here we demonstrated a simple solution for reconciling this contradiction, i.e., the high-speed directional solidification of a ternary eutectic ceramic composite. Its highly textured lamellar and rod-like nanostructures and low-energy interfaces contributed to an outstanding thermal stability that the nanostructure was maintained after being heated at 1573 K for 100 h. It was uncovered that the high solidification rate of 1080 mm/h had an evident restriction on the growth orientation of the faceted crystals during the solidification process, forming a highly textured nanostructure. Combining with the interface energy minimization mechanism, the low-energy interfaces were simultaneously obtained. The evolution of microstructure and interface characteristics during the coarsening process at the higher temperature was further studied. The lamellar structure presented a better thermal stability than that of the rod-like structure since the former had a constraint on the diffusion dimensions. Moreover, a novel structural evolution pattern in the coarsening process was revealed, which was completely different from that of traditional sintered ceramics. The solidified specimens could further keep stable in density, homogeneity of structure and size of internal pores during heat treatment, contributing to a better stability in hardness than that of traditional sintered specimens.
KW - A. Ceramic-matrix composites (CMCs)
KW - A. Layered structures A. Nano-structures
KW - Directional solidification
KW - E. High-temperature properties
UR - http://www.scopus.com/inward/record.url?scp=85173585371&partnerID=8YFLogxK
U2 - 10.1016/j.compositesb.2023.111035
DO - 10.1016/j.compositesb.2023.111035
M3 - 文章
AN - SCOPUS:85173585371
SN - 1359-8368
VL - 266
JO - Composites Part B: Engineering
JF - Composites Part B: Engineering
M1 - 111035
ER -