Properties of tungsten alloys with carbon niobium, tantalum, and zirconium

Pod'yachev, V. N.; Gavrilyuk, M.I.

doi:10.1007/bf00663388

Cited by 8 publications

(1 citation statement)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reduction of the Peierls stress/barrier due to alloying with transition metals with a higher number of valence electrons and the increase for a lower number of valence electrons is supported by existing experimental data. Hardening was observed in W-Zr alloys [54] and softening in W-Re/Ir alloys [8]. Very interesting experimental results for Mo alloys with group VIIIA 3d transition metals were presented by Hiraoka et al [13].…”

Section: The Dislocation Core Structure Peierls Stress and Peierls Ba...mentioning

confidence: 86%

The influence of transition metal solutes on the dislocation core structure and values of the Peierls stress and barrier in tungsten

Samolyuk

Osetsky

Stoller

2012

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

Several transition metals were examined to evaluate their potential for improving the ductility of tungsten. The dislocation core structure and Peierls stress and barrier of 1/2<111> screw dislocations in binary tungsten-transition metal alloys (W(1-x)TM(x)) were investigated using density functional theory calculations. The periodic quadrupole approach was applied to model the structure of the 1/2<111> dislocation. Alloying with transition metals was modeled using the virtual crystal approximation and the applicability of this approach was assessed by calculating the equilibrium lattice parameter and elastic constants of the tungsten alloys. Reasonable agreement was obtained with experimental data and with results obtained from the conventional supercell approach. Increasing the concentration of a transition metal from the VIIIA group, i.e. the elements in columns headed by Fe, Co and Ni, leads to reduction of the C' elastic constant and increase of the elastic anisotropy A = C(44)/C'. Alloying W with a group VIIIA transition metal changes the structure of the dislocation core from symmetric to asymmetric, similarly to results obtained for W(1-x)Re(x) alloys in the earlier work of Romaner et al (2010 Phys. Rev. Lett. 104 195503). In addition to a change in the core symmetry, the values of the Peierls stress and barrier are reduced. The latter effect could lead to increased ductility in a tungsten-based alloy. Our results demonstrate that alloying with any of the transition metals from the VIIIA group should have a similar effect to alloying with Re.

show abstract

Section: The Dislocation Core Structure Peierls Stress and Peierls Ba...mentioning

confidence: 86%