TEM observations of Al72Ni12Co16 decagonal quasicrystal subjected to high-temperature indentation

✍ Scribed by K. Saito; Y. Arakaki; S. Sugawara; R. Shindo; J.Q. Guo; A.P. Tsai

• Book ID: 103840617
• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 673 KB
• Volume: 403
• Category: Article
• ISSN: 0921-5093
• DOI: 10.1016/j.msea.2005.05.048

✦ Synopsis

The effect of high-temperature indentation testing on the microstructural change of a single-grained Al 72 Ni 12 Co 16 decagonal quasicrystal (d-QC) has been investigated by transmission electron diffraction and microscopy (TEM) technique. A definite surface normal to the 10-fold axis of the d-QC was subjected to Vickers indentation test at an elevated temperature of 800 • C with a load of 1 kgf. The TEM investigation of this sample has evidently shown that there are specific types of defects densely distributed in the indented-region, such as grain-boundaries, dislocations and phason-related defects. Furthermore, high-resolution electron microscopy observations have revealed the widespread distribution of nanocrystalline domains in the indented-region, where groups of decagonal atom clusters have a periodic arrangement to form a rhombic lattice. On the basis of these observations, possible deformation mechanisms of the d-QC during high-temperature indentation will be discussed.