Fracture Behavior of Single-Crystal Sapphire in Different Crystal Orientations

Crystals

Xizhao Lu¹  Jiaming Lin²  Qiuling Wen²  Shizhan Huang²  Feng Jiang²  Bicheng Guo²  Ningchang Wang³ 

[1] College of Mechanical Engineering and Automation, Huaqiao University, Quanzhou 361021, China;Institute of Manufacturing Engineering, Huaqiao University, Xiamen 361021, China;Zhengzhou Research Institute for Abrasives & Grinding Co., Ltd., Zhengzhou 450001, China;

关键词: single crystal sapphire;    fracture toughness;    three-point bending test;    single-edge V-notch beam;    cleavage;   

DOI  :  10.3390/cryst11080930

来源: DOAJ

【 摘 要 】

In order to study the anisotropy of fracture toughness and fracture mechanism of single-crystal sapphire, the three-point bending tests and the single-edge V-notch beam (SEVNB) were used to test the fracture toughness of A-plane, C-plane, and M-plane sapphire, which are widely used in the semiconductor, aerospace, and other high-tech fields. Fracture morphology was investigated by a scanning electron microscope and three-dimensional video microscopy. The fracture toughness and fracture morphology of different crystal planes of sapphire showed obvious anisotropy and were related to the loading surfaces. C-plane sapphire showed the maximal fracture toughness of 4.24 MPa·m^1/2, and fracture toughness decreases in the order of C-plane, M-plane, and A-plane. The surface roughness is related to the dissipation of fracture energy. The surface roughness of the fracture surface is in the same order as C-plane > M-plane > A-plane. The fracture behavior and morphology of experiments were consistent with the theoretical analysis. C-plane sapphire cleavages along the R-plane with an angle of 57.6 degrees and the rhombohedral twin were activated. M-plane and A-plane sapphire cleavages along their cross-section.

【 授权许可】

Unknown