Evaluation of fracture toughness of Al-Cu-Fe-B quasicrystal

Abstract

Vickers indentation test, a simple method for the toughness determination, is used to test the fracture toughness of Al₅₉ Cu_25.5 Fe_12.5 B₃ polycrystal’s modulus E, cracking threshold, and fracture toughness have been evaluated. The results show that the Young’s modulus of Al-Cu-Fe-B polycrystalline quasicrystal is evaluated as 134 GPa, and the fracture toughness is about 1.36 MPa^om−1/2. For the Vickers indenter, the cracking threshold is in the range of 250MN−500MN. Moreover, the surface morphology of the indentations and the cracks are observed by means of Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). The relationship between the microstructure of quasicrystal and crack initiation and propagation is discussed in detail.

Keywords

polycrystalline quasicrystal / fracture toughness / cracks

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