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Acta Aeronautica et Astronautica Sinica ›› 2023, Vol. 44 ›› Issue (22): 428598-428598.doi: 10.7527/S1000-6893.2023.28598

• Material Engineering and Mechanical Manufacturing • Previous Articles     Next Articles

Microcrack healing mechanism and microstructure properties of SiC/Al composites modified by high frequency pulse current

Ruifeng LIU1(), Xiaozhe SUN1, Wenhui LI1, Xian WANG2, Jie YAN2   

  1. 1.College of Aeronautics and Astronautics,Taiyuan University of Technology,Jinzhong  030600,China
    2.College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan  030024,China
  • Received:2023-02-22 Revised:2023-03-20 Accepted:2023-03-27 Online:2023-11-25 Published:2023-04-07
  • Contact: Ruifeng LIU E-mail:liuruifeng@tyut.edu.cn
  • Supported by:
    National Natural Science Foundation of China(52205405);Fundamental Research Program of Shanxi Province(20210302124653);Taiyuan University of Technology School Foundation(2022QN151);Science and Technology Innovation Program of Higher Education Institutions in Shanxi Province(2021L068)

Abstract:

High-frequency pulsed current technique was employed to modify the microstructure and performance of as-rolled SiC/Al composites. The microstructure of the composites in different states was observed and analyzed by Scanning Elcetron Microscopy (SEM) and Electron Back-Scattered Diffraction (EBSD). The dynamic healing mechanism of microcrack under high frequency pulse current was investigated. Finally, the micro-nano mechanical properties and tensile properties of the composites were tested. Results show that the high frequency pulse current can effectively promote the static recrystallization of the as-rolled composite.Grain size was refined from 2.47 μm to 2.02 μm, and recrystallization ratio increased from 7.34% to 39.73%, which results in the weakening of the preference orientation. Micro-crack tips prefabricated by the drilling and cold rolling method were partially healed under the action of high temperature and pressure stress induced by high frequency pulse current. Tensile strength and elongation of the as-rolled composites were optimized from 347 MPa and 12.23% to 475 MPa and 21.65% after high frequency pulse current treatment. This research laid the theoretical and practical foundation for the expansion of SiC/Al composites in aviation field.

Key words: SiC/Al composite, high frequency pulse current, grain refinement, microcrack healing, recrystallization

CLC Number: