Enhanced interfacial wettability and mechanical properties of Ni@Al2O3/Cu ceramic matrix composites using spark plasma sintering of Ni coated Al2O3 powders. (February 2021)

• Record Type: Journal Article
• Authors: Feng, Tao; Zheng, Wei; Chen, Wenge; Shi, Yingge; Fu, Yong Qing
• Is Part Of: Vacuum. Volume 184(2021)
• Publication Date: 2021-02
• Subjects: Heterogeneous precipitation -- Ni@Al2O3/Cu composites -- Composite powders -- Interfacial structure; Vacuum -- Periodicals; 621.55
• DOI: 10.1016/j.vacuum.2020.109938
• Languages: English
• ISSNs: 0042-207X

Abstract

Abstract: Poor wettability and weak interfacial bonding between Cu and Al2 O3 have been critical issues for sintering of high-quality Ni@Al2 O3 /Cu composites. In this paper, we explore an interfacial engineering design methodology to achieve good mechanical properties of Ni@Al2 O3 /Cu composites using spark plasma sintering method. The Ni coated powders were prepared using a heterogeneous precipitation method, which can significantly improve wettability between Cu and Al2 O3 and enhance their interfacial bonding. The sintered Ni@Al2 O3 /Cu composites with a copper content of 15 vol% showed a compact network structure of alumina well-infiltrated with metallic Cu, and achieved good mechanical (e.g., fracture toughness of 6.72 MPam 1/2 ) and physical properties (e.g., relative density of 99.3% and electrical resistivity of 1.2810 −3 Ω m). The key mechanisms for the enhanced properties of the composites synthesized using the Ni coated composite powders have been identified as: (1) well-formed ceramic/metal interfacial structures which improve wettability of Al2 O3 with Cu, and promote the formation of a homogeneous network structure; (2) enhanced elemental diffusion and interfacial reactions, which result in formation of Cu2 O and CuAlO2 and thus improve interfacial wetting and bonding properties. Highlights: Ni coated Al2 O3 powders were successfully prepared using a heterogeneous precipitation method. Ni@Al2 O3 /Cu composite showed a compact network structure with metallic Cu, and achieved good properties. Provides the TEM pictures of interfaces between Cu and Al2 O3 phases.