Title: Regarding the Si content associated micro-structural characteristics on the low cycle fatigue behaviour of Al-Si/SiCp composite

Authors: Li Wei; Li Yide; Chen Jian; Li Cong; He Jianjun; Chen Jianlin; Li Chuanchang; Ruan Min

Addresses: School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha, Hunan 410014, China; Key Laboratory of Energy Efficient Clean Utilization, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, Hunan 410014, China ' School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha, Hunan 410014, China; Key Laboratory of Energy Efficient Clean Utilization, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, Hunan 410014, China ' School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha, Hunan 410014, China; Key Laboratory of Energy Efficient Clean Utilization, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, Hunan 410014, China ' School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha, Hunan 410014, China; Key Laboratory of Energy Efficient Clean Utilization, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, Hunan 410014, China ' School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha, Hunan 410014, China; Key Laboratory of Energy Efficient Clean Utilization, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, Hunan 410014, China ' School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha, Hunan 410014, China; Key Laboratory of Energy Efficient Clean Utilization, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, Hunan 410014, China ' School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha, Hunan 410014, China; Key Laboratory of Energy Efficient Clean Utilization, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, Hunan 410014, China ' School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha, Hunan 410014, China; Key Laboratory of Energy Efficient Clean Utilization, Education Department of Hunan Province, Changsha University of Science and Technology, Changsha, Hunan 410014, China

Abstract: The low-cycle fatigue behaviour of the SiCp/Al-Si composites with different Si content (7%, 13% and 20%Si) was investigated. The experimental dates demonstrate that all composites can be described by the Coffin-Manson relationship. The fatigue-ductility coefficient (ε′f) of composite with 7% Si content (2.63) is higher than that of the composite with 13% Si (1.09) and 20% Si (0.85), implying that the composite with a higher Si content exhibits a lower fatigue life. With the increase of the Si content, the degree of cyclic hardening is reduced. It can be ascribed to the increased fracture of the primary Si phase and the formation of micro-cracks originating from the nucleation of many voids at the interface between the Si phase and the matrix. And with the increase of cycles, the connection between the miro-cracks becomes easier, resulting in more serious softening, which causes stress relaxation and offsets part of the hardening effect derived from the increased dislocation density. [Received 21 July 2016; Accepted 24 November 2016]

Keywords: composites; spray deposition; Si content; low-cycle fatigue; fracture.

DOI: 10.1504/IJMR.2017.085419

International Journal of Manufacturing Research, 2017 Vol.12 No.2, pp.177 - 189

Received: 19 Jul 2016
Accepted: 16 Nov 2016
Published online: 25 Jul 2017 *

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