The purpose of this study is to contribute to the knowledge and understanding of stable crack growth and fracture in ductile material under mixed mode load conditions, which has practical significance in metal forming operations. Geometric Moire method was employed to obtain full field deformation and displacement information associated with both stationary and stable crack growth in center inclined cracked specimens for strain hardening material.
Experiments are in progress.
Validity of the Moire experimental results will be verified by developing a numerical method. Boeing Materials Technology, Naval Ship Yard, Bremerton Extensive experimental investigations were conducted on thin aluminum sheet materials in the past few years to study both the short and long fatigue crack propagation using different crack geometries. Microstructure and anisotropic effect on mechanical properties were studied. Presently, fatigue crack growth rate was evaluated by microscopic measurements of crack extension and extensive fractographic examination of fatigued surfaces. Boeing Materials Technology generously supported the graduate student and technicianUs salary, as well as material fabrication of the specimens, allowing use of their laboratory facilities for fatigue pre-cracking of wide plate specimens and final fracture specimen fabrication, as a contribution to PYI research.