INVESTIGATION OF NOTCH FATIGUE BEHAVIOR OF CERTAIN ALLOYS IN THE TEMPERATURE RANGE OF ROOM TEMPERATURE TO -423F

The notched fatigue behavior of 13 alloys was investigated in the temperature range room temperature to -423 F and in the lifetime range 10 to the 4th power to 10 to the 6th power cycles. The alloys studied were chosen on the basis of actual or potential application in missile and spacecraft cryogenic systems. The materials were in sheet form and were fatigued in fully reversed bending experiments. V- notches in the edges of the specimens had theoretical stress concentration factors of about 3.1 and 6.4. The results are presented as S-N plots and comparisons with unnotched fatigue strength are made in tables of notch sensitivity values. S-N plots of the unnotched fatigue data obtained in the previous year are included for convenience.