Low Cycle Fatigue Performance of Materials in a Uniaxial and Multi-Axial Stress Field

The uniaxial and biaxial characteristics of a group of aerospace materials have been evaluated under repeated loads at high stress levels to produce low cycle fatigue failures. Results of the tests are discussed in light of failure theories to determine the most practical procedures for predicting fatigue life.

Fracture analysis data is included for material characteristics such as K_cl, a fracture toughness parameter, and a method of assessing fatigue damage as a function of plastic strain accumulation, is explored.

The test specimens included standard uniaxial test elements, a cross-shaped biaxial specimen, cylindrical pressure vessels, and standard center-notch fracture toughness specimens.