A novel in-situ exothermic assisted sintering high entropy Al2O3/(NbTaMoW)C composites: Microstructure and mechanical properties

doi:10.1016/j.compositesb.2021.108681

	A novel in-situ exothermic assisted sintering high entropy Al2O3/(NbTaMoW)C composites: Microstructure and mechanical properties
	Liu, Diqiang 2,3; Zhang, Aijun 2; Jia, Jiangang 1; Han, Jiesheng 2; Zhang, Junyan 2; Meng, Junhu 2
刊名	Composites Part B: Engineering
	2021-05-01
卷号	212
关键词	Alumina Aluminum Aluminum oxide Bending strength Carbides Composite structures Crack tips Entropy Fracture toughness Molybdenum oxide Sintering Tantalum compounds Interfacial bonding strength Interlocking structure Matrix composite Microstructure and mechanical properties Randomly distributed Second phase strengthening Special structure Strengthening mechanisms
ISSN号	1359-8368
DOI	10.1016/j.compositesb.2021.108681
英文摘要	In this paper, we have designed a Al2O3/(NbTaMoW)C composite by in-situ exothermic reaction, which opened a new field to explore HEC matrix composites. The Al2O3/(NbTaMoW)C composite was synthesized at 1600 °C using Nb, Ta, W, MoO3, Al and graphite powders as raw materials, and the thermite of Al + MoO3 as heat source provides additional energy for the formation of composites. As-prepared composites with relative density 98.5% only exhibited two phases including a high entropy carbide of (NbTaMoW)C and Al2O3 phases, and Al2O3 randomly distributed within high entropy matrix. Phase boundary between (NbTaMoW)C and Al2O3 was a noncoherent interface, resulting in a moderate interfacial bonding strength which was beneficial to both flexural strength and fracture toughness. Moreover, Al2O3 and HEC form an interesting interlocking structure and a grain size varies from 1 μm to 10 μm due to the inhomogeneous temperature distribution introduced by the in-situ exothermic heat. By taking advantages of these special structures, the composites exhibited significantly enhanced mechanical properties compared to (NbTaMoW)C. The flexural strength of composites was up to 530 MPa, and the fracture toughness was 4.5 MPa m1/2. The main strengthening mechanism is second phase strengthening and the presence interlocking structure releases stress intensity at crack tip. © 2021 Elsevier Ltd
WOS研究方向	Engineering ; Materials Science
语种	英语
出版者	Elsevier Ltd
WOS记录号	WOS:000632889600013
内容类型	期刊论文
源URL	[http://ir.lut.edu.cn/handle/2XXMBERH/147689]
专题	材料科学与工程学院
作者单位	1.State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Lanzhou University of Technology, Lanzhou; 730050, China 2.Key Laboratory of Science and Technology on Wear and Protection of Materials, Lanzhou Institute of Chemical Physics, Chinese Academy of Science, Lanzhou; 730000, China; 3.Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing; 100049, China;
推荐引用方式 GB/T 7714	Liu, Diqiang,Zhang, Aijun,Jia, Jiangang,et al. A novel in-situ exothermic assisted sintering high entropy Al2O3/(NbTaMoW)C composites: Microstructure and mechanical properties[J]. Composites Part B: Engineering,2021,212.
APA	Liu, Diqiang,Zhang, Aijun,Jia, Jiangang,Han, Jiesheng,Zhang, Junyan,&Meng, Junhu.(2021).A novel in-situ exothermic assisted sintering high entropy Al2O3/(NbTaMoW)C composites: Microstructure and mechanical properties.Composites Part B: Engineering,212.
MLA	Liu, Diqiang,et al."A novel in-situ exothermic assisted sintering high entropy Al2O3/(NbTaMoW)C composites: Microstructure and mechanical properties".Composites Part B: Engineering 212(2021).