"Endurance limit"
Question:
"I am looking for the endurance limit for stainless steel 440c at hrc 58/62. The only I can find id that T.S.(after heat treated) is 270 ksi and Y.S (after heat treated) is 280 ksi. The fatigue strength for my design is very important."
Answer:
If you believe in such a thing as "endurance limit", you can refer to Mechanical Engineering Design by Shigley & Mischke. For steels with UTS greater than 200 ksi, the endurance limit is listed as 100 ksi. Refer to Section 7-6 in Shigley for more information and data. As for myself, I do not believe in the concept of "endurance limit". It's too easy to make a material fail in fatigue below what is called an endurance limit by simply applying an occasional overload such as may be produced by an earthquake or hurricane loading on a structure.