Ideal strengths of bcc metals

Krenn, C. R.; Roundy, David; Morris, J. W.; Cohen, Marvin L.

doi:10.1016/s0921-5093(01)00998-4

Cited by 104 publications

(68 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Nevertheless,  is only ～0.038G, about 3 times lower than the ideal shear strength predicted by theoretical calculations [17]. This indicates that pristine samples are a necessary, but not sufficient condition to achieve ideal strength.…”

mentioning

confidence: 74%

From “Smaller is Stronger” to “Size‐Independent Strength Plateau”: Towards Measuring the Ideal Strength of Iron

et al. 2015

View full text Add to dashboard Cite

mentioning

confidence: 74%

From “Smaller is Stronger” to “Size‐Independent Strength Plateau”: Towards Measuring the Ideal Strength of Iron

et al. 2015

View full text Add to dashboard Cite

“…Furthermore, the deformation paths provide additional information about the ideal tensile and shear strengths of materials. [89][90][91] Four such paths-tetragonal, hexagonal, orthorhombic, and trigonal 91-93 -were investigated. A detailed definition of the tetragonal, hexagonal, and trigonal paths can be found in Ref.…”

Section: B Deformation Pathsmentioning

confidence: 99%

Bond-order potential for simulations of extended defects in tungsten

et al. 2007

View full text Add to dashboard Cite

We present a bond-order potential (BOP) for the bcc transition metal tungsten. The bond-order potentials are a real-space semiempirical scheme for the description of interatomic interactions based on the tight-binding approximation. In the hierarchy of atomic-scale-modeling methods the BOPs thus provide a direct bridge between electronic-structure and atomistic techniques. Two variants of the BOP were constructed and extensively tested against accurate first-principles methods in order to assess the potentials' reliability and applicability. A comparison of the BOP with a central-force potential is used to demonstrate that a correct description of directional mixed covalent and metallic bonds is crucial for a successful and fully transferable model. The potentials are applied in studies of low-index surfaces, symmetrical tilt grain boundaries, and dislocations. We present a bond-order potential ͑BOP͒ for the bcc transition metal tungsten. The bond-order potentials are a real-space semiempirical scheme for the description of interatomic interactions based on the tight-binding approximation. In the hierarchy of atomic-scale-modeling methods the BOPs thus provide a direct bridge between electronic-structure and atomistic techniques. Two variants of the BOP were constructed and extensively tested against accurate first-principles methods in order to assess the potentials' reliability and applicability. A comparison of the BOP with a central-force potential is used to demonstrate that a correct description of directional mixed covalent and metallic bonds is crucial for a successful and fully transferable model. The potentials are applied in studies of low-index surfaces, symmetrical tilt grain boundaries, and dislocations.

show abstract

“…For a screw dislocation, this leads to K = 119GPa and G = 117GPa, and a core radius of 4.0539Å using the easy-direction ideal strengh σ ideal = 0.11G found by Krenn et al 15 . The ratio K/G, which Chrzan et al propose as a measure of the elastic anisotropy, is 1.01, very close to the isotropic value of one.…”

Section: Core Radii In Real Materialsmentioning

confidence: 92%

“…The stress field is cylindrically symmetric, with the z-axis along the dislocation line, and only the zθ shear component is nonzero; the energy factor of the dislocation, K, depends on the elastic properties of the material and on the orientation of the dislocation. For BCC metals, the ideal strength may be regarded as a fraction of the shear modulus 15 , σ ideal = f G, with G in the direction of shear and thus orientation dependent. (The shear modulus in the [111] direction of BCC alloys is independent of the shear plane.)…”

Section: Dislocation Core Radiimentioning

confidence: 99%

Dislocation core radii near elastic stability limits

2013

View full text Add to dashboard Cite

Recent studies of transition metal alloys with compositions that place them near their limits of elastic stability (e.g. near the body-centered-cubic [BCC] to hexagonal-close-packed [HCP] transition) suggest interesting behavior for the dislocation cores. Specifically, the dislocation core size is predicted to diverge as the stability limit is approached. Here a simple analysis rooted in elasticity theory and the computation of ideal strength is used to analyze this divergence. This analysis indicates that dislocation core radii should diverge as the elastic limits of stability are approached in the BCC, HCP, and face-centered-cubic (FCC) structures. Moreover, external stresses and dislocationinduced stresses also increase the core radii. Density functional theory based total energy calculations are combined with anisotropic elasticity theory to compute numerical estimates of dislocation core radii.

show abstract

Ideal strengths of bcc metals

Cited by 104 publications

References 13 publications

From “Smaller is Stronger” to “Size‐Independent Strength Plateau”: Towards Measuring the Ideal Strength of Iron

From “Smaller is Stronger” to “Size‐Independent Strength Plateau”: Towards Measuring the Ideal Strength of Iron

Bond-order potential for simulations of extended defects in tungsten

Dislocation core radii near elastic stability limits

Contact Info

Product

Resources

About