An X-ray fourier line shape analysis in cold-worked hexagonal titanium base alloys

Abstract

AlloysNominal Compositions (Wt Pct) Alloy I Al-7.35, Mo-0.75, V-0.75, C-0.08 max, Fe-0.3 max, Yt-0.005 max, O 2 -0.2 max, and rest Ti Alloy II Al-6.0, Zr-2.0, Mo-3.

Lattice imperfections in intermetallic Ti–Al alloys: an X-ray diffraction study of the microstructure by the Rietveld method

“…A high density of stacking faults in the a 2 -Ti 3 Al phase was also observed in an earlier study by Karmaker et al [40] in a g-TiAl based alloy employing the conventional Warren-Averbach method of X-ray line profile analysis. Recent studies in Ti-Al intermetallics have confirmed that the addition of Al has the effect of enhancing this fcc faulting sequence by lowering the stacking fault energy in titanium [41]. This leads to high density of stacking faults in the a 2 -Ti 3 Al microstructure during plastic deformation, as is also observed in the present study.…”

“…While, in these powders, the abundance of a 2 -Ti 3 Al was also observed to be lower than in the respective bulk specimens: 17, 9 and 5%, decreasing with increasing Al content. This lowering of volume percentages of a 2 -Ti 3 Al in the powder specimens due to cold-working is an indication of reverse a 2 /g phase transformations due to plastic deformation, which has also been identified and observed in earlier studies [38][39][40][41]. According to Singh and Howe [38], this reverse transformation might be attributed to kinks in the dislocation ledges associated with the motion of interphase g-a 2 interfaces during plastic deformation.…”

Microstructural studies on lattice imperfections in irradiated titanium and Ti-5 Pct Ta-2 Pct Nb by X-ray diffraction line-profile analysis

“…Since a growth fault is absent in an hcp alloy, [24][25][26][27] the values of deformation fault are reported.…”

Microstructure characterization of titanium-base aluminium alloys by X-ray diffraction using Warren–Averbach and Rietveld method

“…11.2 and 20.1 reflections were not considered because profiles were found to be too weak to be recorded. The detailed Fourier line shape analysis [10,[24][25][26] have been performed on the hcp system considering the fault-unaffected (H-K = 3N) for 10.0, 00.2 and 11.0 and fault-affected (H-K = 3N ± 1) 10.1, 10.2 and 10.3 reflections by using the equations worked out by Warren and Averbach in their method of Fourier analysis [10] of imperfections in metallic alloys [4,7,[10][11][12][13][14]. This method employs the deconvolution Fourier-transform method (known also as the Stokes method) for the determination of the intrinsic physical line profile, followed by the Fourier method for evaluation of lattice imperfection.…”

“…have been of much interest in recent years as structural materials for elevated temperature strength, oxidation and corrosion resistance applications [1][2][3][4][5][6][7]. With increasing interest from aerospace and automotive communities, significant progress has been made in the research and development of Ti-base Al alloys.…”