1998 Fiscal Year Final Research Report Summary
Strength Evaluation Based on Singular Stress Field Around Interface of Jointed Dissimilar Materials
Project/Area Number |
09450054
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Materials/Mechanics of materials
|
Research Institution | Science University of Tokyo |
Principal Investigator |
CHEN Dai-heng Science University of Tokyo Faculty of Engineering Professor, 工学部, 教授 (90217266)
|
Project Period (FY) |
1997 – 1998
|
Keywords | Interface / Stress singularity / Composite Material / Stress intensity factor / Stress Concentration / Fracture Mechanics / Elastic-plastic singular stress field / Interface crack |
Research Abstract |
In the present study, a practical method is introduced to analyze the plastic stress singularity occuring in a V-notch. The results so obtained appear to be quite satisfactory. Based on the numerical results, the effects of the notch geometry and the hardening power on the singularity are discussed. In particular, an approximate expression is presented for the evaluation of s. Also, a method of evaluating the static strength of a V-shaped notch based on stress intensity factors of the notch is proposed. The singular stress field at the notch tip is defined by two parameters, K_<I,lambda1> and K_<II,lambda2>, which correspond to the intensities of the symmetric stress field and the skew-symmetric field, respectively. It is found that the fracture values K_<I,lambda1> and K_<II,lambda2> are almost constant independent of the notch depth and the loading conduction. Four kinds of fracture criteria are considered ; two of them are based on the tensile strength siguma_B and the other two are based on the fracture toughness K_<IC>. The usefulness of the criteria is investigated through the experimental results.
|