I have a shaft with a keyway in it. Torque is transmitted to the shaft via the keyway. I want to calculate the maximum stress (von mises) at the keyway.

The shear [t] is Tr/J. The bearing stress [s] from the key is force from the torsion/area of the keyway side wall (-the key chamfer). Does the maximum von mises stress take into account both the shear from torsion as well as the bearing stress from the key?

In other words, is my von mises stress just (3)^.5 * t or is it (s^2+3t)^1/2? If its just shear, is it because the bearing stress is neglected?

Thanks,

Todd