Accession Number : AD0656481

Title :   THERMAL FATIGUE DAMAGE UNDER A TWO-STRAIN-BLOCK HISTORY.

Descriptive Note : Final rept. 1 Jul 63-1 Jul 67,

Corporate Author : SEATTLE UNIV WASH DEPT OF MECHANICAL ENGINEERING

Personal Author(s) : Majors,Harry , Jr

Report Date : JUN 1967

Pagination or Media Count : 119

Abstract : Thermal-strain fatigue, two block strain cycling, axial tension-compression tests were performed on thin-walled tubes of annealed, type 200 nickel to study the plastic strain damage process that leads to failure in the range of 10,000 to 100,000 cycles at a mean temperature of 580F under a frequency of 60-90 cycles per hour. Plastic strain ranges are in the order of twenty to forty per cent of the total strain range. All tests showed a transient period in the first 100 cycles prior to the stress-strain hysteresis loops stabilizing. A cumulative damage theory was developed which led to the relationship for a two-strain block history. (Author)

Descriptors :   (*NICKEL, FATIGUE(MECHANICS)), THERMAL STRESSES, STRAIN(MECHANICS), DAMAGE, CRACKS, PLASTIC PROPERTIES, COMPRESSIVE PROPERTIES

Subject Categories : Metallurgy and Metallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE