Head, Fracture Mechanics Section, Naval Research Laboratory, Washington, D.C.
Captain, Escuela Superior de la Fuerza Aerea Venzzolana,
Pages: 12 Published: Jan 1984
Studies have shown that fatigue growth of semielliptic surface flaws in plates is not adequately predicted solely by stress intensity factor analysis. The variation in stress field triaxiality along the flaw border must be an important factor contributing to differences between predicted and observed fatigue crack growth behavior. An analysis is formulated to examine surface flaw fatigue growth accounting for constraint variation using the concept of crack closure. The extent of crack closure is quantified for plane stress versus plane strain conditions. Changes in the geometric parameters describing flaw size and shape are studied. Applications of the analysis are compared with experiments. The use of the concept of crack closure to account for constraint variation along the border of a surface flaw yields excellent results.
fracture mechanics, fatigue (materials), surface flaw, fatigue crack growth
Paper ID: STP32561S