HAYNES® 188 alloy exhibits very good low cycle fatigue properties at elevated temperatures. Results shown below are for strain-controlled tests run in the temperature range from 800°F (425°C) to 1600°F (870°C). Samples were machined from bar. Tests were run with fully reversed strain (R = -1) at a frequency of 20 cpm (0.33 Hz).
The graph below compares the low cycle fatigue lives of a number of alloys tested at 800°F (425°C) in both the as-received and 1400°F (760°C)/1000 hour pre-exposed condition. Samples were machined from plate or bar, after exposure for exposed samples. Tests were again run with fully reversed strain (R = -1) at a frequency of 20 cpm (0.33 Hz). TSR = Total Strain Range.