Acta Mechanica Solida Sinica

, Volume 21, Issue 4, pp 337–346

# Method to Calculate Stress Intensity Factor of V-Notch in Bi-Materials

• Youtang Li
• Ming Song
Article

## Abstract

Based on Zak’s stress function, the eigen-equation of stress singularity of bi-materials with a V-notch was obtained. A new definition of stress intensity factor for a perpendicular inter-facial V-notch of bi-material was put forward. The effects of shear modulus and Poisson’s ratio of the matrix material and attaching material on eigen-values were analyzed. A generalized expression for calculating KI of the perpendicular V-notch of bi-materials was obtained by means of stress extrapolation. Effects of notch depth, notch angle and Poisson’s ratio of materials on the singular stress field near the tip of the V-notch were analyzed systematically with numerical simulations. As an example, a finite plate with double edge notches under uniaxial uniform tension was calculated by the method presented and the influence of the notch angle and Poisson’s ratio on the stress singularity near the tip of notch was obtained.

## Key Words

bi-material V-notch eigen-equation stress intensity factor finite element method

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© The Chinese Society of Theoretical and Applied Mechanics and Technology 2008

## Authors and Affiliations

• Youtang Li
• 1
• 2
• Ming Song
• 2
1. 1.Key Laboratory of Digital Manufacturing Technology and ApplicationMinistry of Education, Lanzhou University of TechnologyLanzhouChina
2. 2.College of Mechano-Electronic EngineeringLanzhou University of TechnologyLanzhouChina