X‐ray topography study of deformed composites obtained by directional solidification of Al‐Cu‐Co alloy

Abstract

Fibre-reinforced composites were produced by the modification of the static horizontal Bridgman method. The single-crystalline composite matrix consisted of the tetragonal T phase (Al 72 Cu 27 Co 1 ). Decagonal quasicrystal D phase (Al 64 Cu 20 Co 16 ) was the reinforcement in the form of fibres parallel to the solidification direction. These fibres were surrounded by the tetragonal Θ phase (Al 66 Cu 31 Co 3 ). The composite specimens in the shape of plates were studied by tensile tests and X-ray topography. The specimens deformed up to rupture and, from the X-ray topographs, the dependence of the composite structure defects on deformation was examined. It was found that the rupture of specimens is related to low-angle boundaries created during deformation. The influence of defects on the strength of the composites is discussed.

Influence of Heat Treatment on Defect Structures in Single-Crystalline Blade Roots Studied by X-ray Topography and Positron Annihilation Lifetime Spectroscopy

“…Specific contrast is also created for other defects that occurred in the single-crystalline materials. [13,23] The misorientation angle may be calculated using the shift value in the topograms. [13] The minimal misorientation angle, determined by X-ray topography method, is on the order of arc minutes, which are much lower than for the EBSD method.…”

Characterization of Al_65.0Cu_32.9Co_2.1 Alloy Containing Nanofibres

“…1. The measured diffraction angles of 2θ were recalculated in d-spacing and compared with data collected previously [11]. The TEM electron diffraction patterns were obtained from selected areas of the samples.…”

Characterization of Composite Based on Al–Cu–Co Alloy

“…The crystalquasicrystal (CQ) composites can be produced ex situ by powder metallurgy methods [2] or in situ by directional solidification [3]. In this paper the modified horizontal Bridgman method was used for obtaining CQ fibrous composite [4]. Due to specific atomic structure, decagonal aluminium based quasicrystal phases posses many useful anisotropic properties such as an anisotropic resistivity, magnetization and magnetoresistivity [5].…”