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Shaft sizing question

  1. Oct 16, 2008 #1
    Attempting to use the formula:
    D = 1.72 (Tmax/σmax)^1/3

    In my case I do not know σmax or at least how to calculate it from material properties.
    Material is 1045
    UTS 84800
    YTS 74300
    Tmax = 591.55 in-lbs

    D = 1.72 (Tmax/σmax)^1/3

    Any help would be appreciated.

  2. jcsd
  3. Oct 17, 2008 #2


    User Avatar
    Science Advisor

    As a very rough pass, you can use your yield strength as [tex]\sigma_{max}[/tex]. Your equation is essentially assuming a set relationship for ductile materials and the relationship between shear stresses and normal stresses. This is for static, pure shear only.
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