Generalised stacking fault energies of copper alloys - density functional theory calculations

Abstract

Generalised stacking fault energies of copper alloys have been calculated using density functional theory. Stacking fault energy of copper alloys is correlated with the d-electrons number of transition metal alloying element. The tendency to twiningis also modified by the presence of alloying element in the deformation plane. The results suggest that Cu-transition metal alloys with such elements as Cr, Mo, W, Mn, Re are expected to exhibit great work hardening rate due to the tendency to emission of the partial dislocations.

Modeling the Effects of Varying the Ti Concentration on the Mechanical Properties of Cu–Ti Alloys

“…The MD simulations show that with an increase in Ti concentration, there is a corresponding reduction in the formation of stacking faults and, thus, an increase in the stacking fault energy (SFE). The latter result is consistent with previous studies, , which emphasize that 3D transition metals like Ni, when introduced into Cu at concentrations up to 5% are expected to increase the strength and hardness of the metal due to solid–solution hardening, leading to an increase in the SFE.…”

Novel Candidates for Palladium Alloys – Enhanced Strength and Ductility - Generalized Stacking Fault Energy Calculations

“…Similar calculations have been performed for Cu, where thirty Cu alloys were examined from the point of view of SF and twins formations [10]. The Cu-GSFE calculations showed that 6-7 VEs TMs elements have a significant effect on the SFE/USFE ratio, but twinnability is only slightly modified by impurity.…”

“…Tadmor's and Bernstein's method is based on the estimation of the generalized stacking fault energy (GSFE) for specific alloys. GSFE has been computed for a number of fcc metals and their alloys, including Al [7], Cu [10], Ni [11]. Experimental examination confirmed that GSFE calculations predicted correctly the lower SFE and twinning occurrence.…”

“…Analysis of the nucleation of dislocation from the crack tip leads to understanding that depth of SF and TE compared to USFE and UTE is crucial for the preferred deformation mechanism, respectively. When the analyzed alloying element causes these parameters to be lower than in pure metal (a comparable state), the PDE and MT are facilitated [10]. As can be seen from SFE/USFE ratio, the formation of SF is facilitated by alloying elements, which decrease the SFE and increase the USFE compared to Pd (the reference value of pure Pd is marked by black tiny lines in Figure 2 and Figure 3).…”

“…Palladium SFE is equal 148 mJ/m 2 (i.e. SFE of Cu is 45 mJ/m 2 [10], SFE of Al is 162 mJ/m 2 [12]). SFE values for Pd alloys showed characteristic trend with a minimum for 5-6 VEs (3d: V, 4d: Mo, 5d: W).…”