Session: 01-07-01: Nonlinear Problems in Aerospace Structures

Paper Number: 105345

105345 - Practical Ductile Fracture Criterion Model for Metallic Aerospace Structure Static Strength Evaluations 

A practical ductile fracture criterion model is developed, which is well suited for the aerospace structure static strength evaluations using detailed finite element analysis.  The model is based on the classical Coulomb-Mohr fracture criterion and extended to handle strength anisotropy commonly present in aerospace structural metal materials through the application of stress linear transformation.

The resulting model (TCM: Transformed Coulomb-Mohr model) employs the model parameter identification procedure which utilizes the well-established statistically based material allowable database like MMPDS. Therefore it is relatively easy to establish a MMPDS-compatible TCM model database covering wide range of aerospace structural materials, which makes it usable for the real-world large scale airframe development projects.

To demonstrate the predictive capability of the TCM model, static strength tests for several structural elements are conducted and evaluated. Comparison of TCM model predictions against the ones by two other approaches, namely traditional design chart methods, and naive FE-based evaluation utilizing von Mises stress and Ftu, clearly shows the superior capability of the TCM model approach.

 

Keywords: metallic material, ductile fracture, anisotropy, static strength evaluation, Transformed Coulomb-Mohr

Presenting Author: Tsutomu Yoshida Kawasaki Heavy Industruies, Ltd.

Presenting Author Biography: Tsutomu Yoshida is a structural analysis specialist at Aerospace Systems Company, Kawasaki Heavy Industries, Ltd.
In his over 38 years of carrier at Kawasaki, he has been involved in various aerospace development projects including JSDF (Japan Self-Defense Forces) XT-4 trainer and FS-X fighter, Embraer 170, Boeing 7J7 and 787, as well as some in-house and contract structural research activities.
His professional area of interest has always been the application of computational analysis technologies to demystify the behavior of complex aerospace structure, especially with metallic materials.

Authors:

Tsutomu Yoshida Kawasaki Heavy Industruies, Ltd.
Takuya Ishida Kawasaki Heavy Industries, Ltd.