Accession Number : AD0617915

Title :   A FLEXURAL FATIGUE MACHINE FOR HIGH-TEMPERATURE OPERATION AT RESONANCE IN VACUUM.

Descriptive Note : Interim rept.,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON D C

Personal Author(s) : ACHTER,M. R. ; Smith,H. H. ; Stegman,R. L. ; Riley,R. J.

Report Date : 11 JUN 1965

Pagination or Media Count : 17

Abstract : A resonance type reversed-bending, high-temperature fatigue machine for operation at constant bending amplitude in vacuum has been developed. The vibration frequency is maintained at resonance by means of a feedback circuit employing a capacitance pickup. Another circuit maintains a constant amplitude of vibration. As fatigue cracks are developed, the resonant frequency is reduced. Curves of resonant frequency versus time at 800C for materials of high damping, such as Type 316 stainless steel, and for materials of low damping, such as Inconel X, illustrate the development of fatigue damage. (Author)

Descriptors :   (*TEST EQUIPMENT, FATIGUE(MECHANICS)), (*FATIGUE(MECHANICS), TEST EQUIPMENT), VACUUM APPARATUS, HIGH TEMPERATURE, DEFORMATION, RESONANCE, VIBRATION, FRACTURE(MECHANICS), STAINLESS STEEL, NICKEL ALLOYS, CHROMIUM ALLOYS, TITANIUM ALLOYS, DAMPING, FEEDBACK, CIRCUITS

Distribution Statement : APPROVED FOR PUBLIC RELEASE