Accession Number:

AD0648154

Title:

LOW-CYCLE FATIGUE BEHAVIOR OF INTERNALLY PRESSURIZED BOXES.

Descriptive Note:

Research and development rept.,

Corporate Author:

NAVY MARINE ENGINEERING LAB ANNAPOLIS MD

Personal Author(s):

Report Date:

1967-03-01

Pagination or Media Count:

38.0

Abstract:

One phase of a continuing study of the low-cycle fatigue behavior of metals for deep-submergence structural applications involves the validity of simple specimen results when applied to complex structures. As part of this study, the low-cycle fatigue performance of internally pressurized boxes was investigated. The boxes were constructed from 1-inch-thick plate of 11 materials consisting of six steels, one aluminum alloy, one cupronickel alloy, and three titanium alloys. A previous report described the results obtained from 12 boxes. This report describes the results obtained from an additional 15 boxes. The results provide additional confirmation of conclusions obtained from simple specimen tests, i.e., 1 increases in low-cycle fatigue strength for a given life are not proportional to increases in yield strength, and 2 low-cycle fatigue life is closely related to total strain range and appears to be independent of both structural metal and strength level in the life range of 1,000 to 30,000 cycles. Conclusions are also reached regarding effects of such variables as joint geometry, corrosivity of environment, stress relief, and notch toughness. Author

Subject Categories:

  • Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE