DETERMINATION OF CRITICAL LENGTH PARAMETER FOR FATIGUE LIFETIME PREDICTIONS OF NOTCHED SPECIMENS.

The paper reviews the research results to date on critical length parameters of notched aluminum specimens with various notch radii. The Theory of Critical Distances (TCD) was applied in form of the Line Method for the determination of the critical length parameter. This parameter can be used for lifetime predictions of notched components. The output is a comparison of critical length parameters of specimens with various notch radii. Numerical calculations as well as experimentally obtained data were employed in the analysis. Fatigue experiments were performed at fatigue loading device working at ultrasonic frequency of 20 kHz. Thus we were able to reach very high number of cycles to failure. [ABSTRACT FROM AUTHOR]