Texture and Differential Stress Development in W/Ni-Co Composite after Rotary Swaging

0531359 - ÚJF 2021 RIV CH eng J - Journal Article
Strunz, Pavel - Kocich, R. - Canelo-Yubero, David - Macháčková, A. - Beran, Přemysl - Krátká, L.
Texture and Differential Stress Development in W/Ni-Co Composite after Rotary Swaging.
Materials. Roč. 13, č. 12 (2020), č. článku 2869. E-ISSN 1996-1944
R&D Projects: GA ČR(CZ) GA19-15479S; GA MŠMT LM2015056
Grant - others:AV ČR(CZ) StrategieAV21/23
Program: StrategieAV
Research Infrastructure: Reactors LVR-15 and LR-0 II - 90120
Institutional support: RVO:61389005
Keywords : tugensten heavy alloys * rotary swaging * neutron diffraction * resdual stress * texture
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 3.623, year: 2020
Method of publishing: Open access
https://doi.org/10.3390/ma13122869

Knowledge of texture and residual stresses in tungsten heavy pseudoalloys is substantial for the microstructure optimization. These characteristics were determined in cold and warm rotary swaged W/NiCo composite with help of neutron diffraction. The results were discussed in view of the observed microstructure and mechanical properties. The investigated bars consisted of tungsten agglomerates (bcc lattice) surrounded by NiCo-based matrix (fcc lattice). No preferential crystallographic orientation was found in the as-sintered bar. A strong texture was formed in both the tungsten agglomerates ( fiber texture parallel to the swaging axis) and in the NiCo-based matrix ( fiber texture) after rotary swaging. Although usually of double-fiber texture, the fiber of the fcc structures was nearly missing in the matrix. Further, the cold-swaged bar exhibited substantially stronger texture for both phases which corresponds to the higher measured ultimate tensile strength. The residual stress differences were employed for characterization of the stress state of the bars. The largest residual stress difference (approximate to 400 MPa) was found at the center of the bar deformed at room temperature. The hoop stresses were non-symmetrical with respect to the swaging axis, which was likely caused by the elliptical cross section of the as-sintered bar.
Permanent Link: http://hdl.handle.net/11104/0310028