Stresses at end-milled keyways in plain shafts subjected to tension, bending, and torsion

Abstract

The frozen-stress photoelastic technique has been used to determine the complete surface stress field in empty keyways of British Standard proportions for rectangular keys. A method is included for the photoelastic analysis of general surface stresses in doubly curved surfaces with one small radius. The ratio of measured stress to stress in the same fibre in a shaft without keyway is the same for bending and tension. Stress indices for combined bending and torsion have been calculated for one fillet-radius ratio. A simple method is presented for obtaining a close upper bound for the peak stress in any B.S. keyway for rectangular keys subjected to any combination of bending and torsion.