Improved method for severe thermal shocks testing of ceramics by water quenching

The thermal shock testing of ceramics by water quenching in a bath of water at room temperature is a very popular one because of its simplicity. However it presents some disadvantages, the most critical of them being the water phase changes in the sample vicinity which strongly affect heat exchanges between sample and water. This study proposes a new experimental technique which minimizes the previous phase changes in order to perform severe thermal shocks. The sample, uniformly heated at a temperature higher than the boiling water temperature, is suddenly cooled in periphery by a system of water jets at room temperature. The water flow is sufficiently high to insure a permanent contact of the sample periphery with water in liquid state. So, the surface heat exchanges are significantly greater than those developed during a thermal shock by immersion and thus make it possible to approach the conditions of very severe thermal shock.