Stress Prediction And Measurement In Chemical Toughening

The interaction between stress development due to diffusive ion exchange and viscoelastic stress relaxation is discussed and a specific model is described. In some circumstances the peak stress is expected to occur below rather than at the surface. Stress measurement techniques using the waveguide effect in the surface layers become unreliable when this is the case. Modelling of the direct and inverse waveguide problems is used to explore the behaviour of a particular measurement technique.