Photoelastic Stress Analysis
A Plane Polarascope
Anisotropic elastic materials exhibit shear waves when stressed. Certain transparent materials exhibit birefringent properties when stressed
When this child's toy is viewed between crossed polar's ( Dark field ) the locked in stress due to the hot plastic cooling in the injection machine mould can be seen as coloured fringes
Models are made of birefringent material and loading applied when viewed between crossed polar's the stress patterns can be seen
Crack propagation notch tests
A Lifting Eye modeled in Perspex and placed under load in a Polarascope
Work In Progress - I will add more as notes surface from the depths of my 'filing system'
© 1980 - 2008 Phil Gee