In your website, it is stated that “allowable stress should be within the elastic limit of the material. If the surface condition is good, the maximum static stress should be 75% or less of the tensile strength.” What is the maximum static stress of flat springs made of SK-5 material? Sorry for asking you such a beginner question.
Spring Newbie, hello!
Since the tensile strength varies depending on the hardness range of the material used, the lower limit of the hardness range is converted to the tensile strength, and 75% of that value is the static maximum stress.
For example, if the hardness range of the material used is HV460 to 500, HV460 will be converted to tensile strength which equals 1530N/mm^2, and 75% of that is 1147.5N/mm^2, is the static maximum stress.
Thank you for your answer.
“Allowable stress is within the elastic limit of the material”, but is the elastic limit point (upper limit point) the value of the tensile strength itself (not 75%) converted from the hardness in your answer?
When the bending stress is applied to the flat springs, the bending stress can be up to 75% of the tensile strength in static use.
The tensile strength itself is a value that exceeds the elastic limit of the material in terms of bending stress.
