Accession Number : ADA307047

Title :   Development of Equipment and Techniques for Complex Fatigue Loading. Phase 1.

Descriptive Note : Final rept.,

Corporate Author : AEROPROJECTS INC WEST CHESTER PA

Personal Author(s) : Kartluke, Herbert ; Luckhardt, Philip G. ; Pruder, Gary D.

PDF Url : ADA307047

Report Date : DEC 1966

Pagination or Media Count : 77

Abstract : Fatigue testing apparatus for simultaneous application of high-frequency, low-frequency, and static loading was designed and constructed. The equipment provided for the introduction of high-frequency vibratory energy at l5,000 cycles per second at one end of a specimen and static loading and low-frequency vibration at 2000 cycles per minute at the opposite end. Specimens with a necked-down test section were designed for resonance at the high frequency, and the specimen holding arrangement insured effective delivery of the high-frequency energy into the specimen. The feasibility of the apparatus as a fatigue test instrument was demonstrated in limited tests on integral specimens of 4340 steel, 2014-T6 aluminum alloy, and 6Al-4V titanium alloy, and on joint specimens of 4340 steel involving fusion-welded, riveted, adhesive-bonded, and brazed joints with constant low-frequency and static loads, the specimens generally demonstrated shorter elapsed time to failure as the high-frequency power input was increased. The titanium alloy, however, appeared to be insensitive to the high-frequency vibration at the power levels used, possibly because of its internal hysteresis characteristics. The equipment provides a means for laboratory testing of materials and joint designs for knowledge of materials behavior under conditions encountered in rocket-propelled vehicles. It was recommended that comprehensive fatigue testing be carried out with this apparatus and that methodology be evolved for evaluation and use of the test data.

Descriptors :   *ALLOYS, *FATIGUE(MECHANICS), *ROCKET PROPULSION, DENSITY, HIGH FREQUENCY, VIBRATION, STRESS ANALYSIS, ALUMINUM ALLOYS, LOADS(FORCES), STATIC LOADS, MODULUS OF ELASTICITY, STEEL, FEASIBILITY STUDIES, SYNCHRONISM, YIELD STRENGTH, LOW FREQUENCY, HYSTERESIS, FATIGUE TESTS(MECHANICS), TITANIUM ALLOYS, BRAZING, ADHESIVE BONDING, FUSION WELDING, RIVETED JOINTS.

Subject Categories : Properties of Metals and Alloys
      Mechanics
      Rocket Engines

Distribution Statement : APPROVED FOR PUBLIC RELEASE