At the moment, we design flat springs using SUS301CPS-H material. There is no problem in designing with SUS301CSP-H, but other than that, designing with other materials (quenching and tempering SK5 to make it equivalent to CSP-H) is very difficult.
What do you think is the problem?
In addition, we are currently designing a highly rigid flat spring, and since SUS material has a limited thickness, we use SK material this time. It would be much appreciated if you could tell us about materials with higher fatigue strength than SUS301CSP-H.
Would you please give us the S-N curve of those materials too?
The tensile strength of SUS301-CSP-H material with a thickness of 1.5 mm or less is 1320 N/mm2 or more, but the tensile strength of SK5-CSP material is about 1510 N/mm2 with a thickness of 1 mm or less and 1330 N /mm2 with a thickness of 1 mm or more.
Therefore it is stronger than SUS301-CSP-H.
As you pointed out, the materials with higher fatigue strength than SUS301CSP-H are SK85 (SK5) and SUP10 materials.
For the durability limit diagram, see “Spring Technology Information”-“Flat Springs”-“How To Calculate The Spring Stress” on our website.
