Modelling liquid impact fracture thresholds in brittle materials

The present paper discusses the theoretical modelling of liquid impact damage thresholds as a result of spatial and temporal distributions of transient stresses in elastically deformable brittle materials. The model predicts changes in the response characteristics of brittle materials owing to an idealised representation of a droplet of water impacting a plane surface. The analytical approach used does not include the effect of lateral outflow of water and is therefore only applicable to the first stages of impact where the compressibility of water in the droplet is most significant. The predicted response characteristics are compared with experimental data generated using controlled liquid jet impacts produced by the Cavendish Laboratory’s multiple impact jet apparatus (MIJA). The predicted responses of a selection of infrared transmitting materials compare well with experimental results. The results illustrate the importance of the first stages of liquid impact.