On the Diffusion Theory of Kink-Pair Formation on Dislocations

1982 ◽  
Vol 111 (2) ◽  
pp. 541-553 ◽  
Author(s):  
E. Mann
Keyword(s):  
Diffusion Theory ◽  
Pair Formation ◽  
Kink Pair

Peierls Stresses Estimated from CRSS Vs. Temperature Curve and their Relation to the Crystal Structure

2011 ◽  
Vol 465 ◽  
pp. 97-100 ◽  
Author(s):  
Yasushi Kamimura ◽  
Keiichi Edagawa ◽  
Shin Takeuchi
Keyword(s):  
Crystal Structure ◽  
B Value ◽  
Pair Formation ◽  
Temperature Curve ◽  
Peierls Stress ◽  
Material Parameters ◽  
Bcc Metals ◽  
Kink Pair ◽  
Data Points ◽  
Critical Resolved Shear Stress

Peierls stresses P of a variety of pure crystals, bcc metals, NaCl type crystals, elemental and compound tetrahedrally coordinated crystals, intermetallic compounds and ceramic crystals, have been estimated from the critical resolved shear stress (c) vs. temperature curves. For high P crystals where CRSS data are available only at high temperatures, P has been estimated from the critical temperature T0 at which steep temperature dependence of c vanishes: T0 is related to the kink-pair formation energy which is a function of P, material parameters and dislocation character controlling the deformation. The estimated p/G values are semi-log plotted against h/b value, where G is the shear modulus, h the slip plane spacing and b the Burgers vector. Two facts should be noted. First, P/G values for a group of crystals with the same crystal structure are within a range of a factor of 10. Second, most of the data points lie in between the classical Peierls-Nabarro relation and the Huntington’s modified relation. These facts indicates that Peierls stress is primarily determined by the crystal structure.

Atomistic characterization of three-dimensional lattice trapping barriers to brittle fracture

2006 ◽  
Vol 462 (2070) ◽  
pp. 1741-1761 ◽  
Author(s):  
Ting Zhu ◽  
Ju Li ◽  
Sidney Yip
Keyword(s):  
Brittle Fracture ◽  
Crack Front ◽  
Interatomic Potential ◽  
Reaction Pathway ◽  
Minimum Energy ◽  
Three Dimensional ◽  
Pair Formation ◽  
Cleavage Crack ◽  
Dimensional Lattice ◽  
Kink Pair

We present a detailed account of an atomistic study of three-dimensional lattice trapping barriers to brittle fracture in Si. By means of a prototypical interatomic potential model, we map out the molecular details of the evolution of atomically sharp cracks in the (111) cleavage plane with straight crack fronts along the and directions, respectively. The thermally activated processes of bond rupturing along the crack front are quantitatively characterized using a reaction pathway sampling scheme. The calculated minimum energy paths reveal a mechanism of kink-pair formation and migration in facilitating the crack front advancement. We show that the physical origin of directional anisotropy in cleavage crack propagation can be attributed to a difference in the kink-pair formation energy for different crack orientations. The effects of interatomic potentials are delineated by comparing the Stillinger–Weber model with an environment-dependent model.

The problem of kink pair formation in f.c.c. metals

1994 ◽  
Vol 211-212 ◽  
pp. 111-113 ◽  
Author(s):  
G. Gremaud ◽  
B. Quenet ◽  
W. Benoit
Keyword(s):  
Pair Formation ◽  
Kink Pair

Inertial motion and multi-kink pair formation of dislocations on the Peierls potential

1993 ◽  
Vol 67 (5) ◽  
pp. 1153-1160 ◽  
Author(s):  
Takayoshi Suzuki ◽  
Hirokazu Koizumi
Keyword(s):  
Pair Formation ◽  
Inertial Motion ◽  
Kink Pair
Sign in / Sign up

Export Citation Format

Share Document