Design features and results from fatigue reliability research machines.The design, fabrication, development, operation, calibration and results from reversed bending combined with steady torque fatigue research machines are presented. Fifteen-centimeter long, notched, SAE 4340 steel specimens are subjected to various combinations of these stresses and cycled to failure. Failure occurs when the crack in the notch passes through the specimen automatically shutting down the test machine. These cycles-to-failure data are statistically analyzed to develop a probabilistic S-N diagram. These diagrams have many uses; a rotating component design example given in the literature shows that minimum size and weight for a specified number of cycles and reliability can be calculated using these diagrams.
Document ID
19720027848
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Lalli, V. R. (NASA Lewis Research Center Spacecraft Technology Div., Cleveland, Ohio, United States)
Kececioglu, D. (Arizona, University Tucson, Ariz., United States)
Mcconnell, J. B. (Hughes Engineering Laboratory Tucson, Ariz., United States)
Date Acquired
August 6, 2013
Publication Date
October 1, 1971
Subject Category
Facilities, Research, And Support
Meeting Information
Meeting: Society for Experimental Stress Analysis, Fall Meeting