Stress intensity factors for crack tip shielding or anti-shielding by impurity atoms

✍ Scribed by J. Weertman; J. E. Hack

• Book ID: 104615480
• Publisher: Springer Netherlands
• Year: 1986
• Tongue: English
• Weight: 247 KB
• Volume: 30
• Category: Article
• ISSN: 1573-2673
• DOI: 10.1007/bf00019709

✦ Synopsis

The average value of the crack tip stress intensity factor produced by a row of impurity atoms is calculated in this paper. The row of impurity atoms lies parallel to the crack front and is situated at an arbitrary position about a crack. The impurity atom produced mode I shielding/antishielding stress intensity factor Lis for a row

of impurity atoms very close to the crack tip is given by the expression: Lie = k cos~ ~--)I ~ ] where 2a is the crack length, a* is either the atomic radius of the host atoms (for substitutional impurities) or the radius of the vacant interstitial site (for interstitial impurities), k = c r 0 ~ and % = G c { / 2 where G is the shear modulus, c is the fraction of impurity atoms in the impurity atom row and { is the misfit parameter of the impurity atoms, r 2 is the distance from the crack tip, and 02 is the angle the radius r 2 makes with the crack plane.