Article

Residual microstructure associated with impact craters in TiB2/2024Al composite.

School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
Micron (Impact Factor: 1.88). 02/2012; 43(2-3):344-8. DOI: 10.1016/j.micron.2011.09.011
Source: PubMed

ABSTRACT Residual microstructures associated with hypervelocity impact craters in 55 vol.% TiB(2)/2024Al composite were investigated by transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). TiB(2)-Al interface, TiB(2) particles and Al matrix before and after hypervelocity impact were compared to discuss the effect of hypervelocity impact. A new Al(x)O(1-x) phase with the fcc structure and the crystal parameter of 0.69 nm was formed at TiB(2)-Al interface. Stacking fault with width of 10-20 nm was formed along the (001) plane of TiB(2) particle. Formation of nanograins (≈ 100 nm) was observed within Al matrix, moreover, lamellar S' phase was transformed into lenticular or spherical S phase after hypervelocity impact.

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