Studying the ultrasonic characterization of industrial plasters

International audienceSaint-Gobain produces building materials made from plaster. These are materials containing gypsum and air scatterers. The latter strongly influence the mechanical strength and the volume density. Solutions for ultrasonic non-destructive characterization are designed to enable a better understanding of the influence of process parameters and to optimize this process. The model of homogenisation of Waterman-Truell is chosen to simulate the propagation of compression waves in the plaster medium. Validation tests of the model using ultrasound by immersion were set up for samples in vacuum sealed bag. The test results are close to those obtained from the model. The first results of characterization by ultrasonic air are also presented. The potential for non-destructive characterization of plaster using non-contact ultrasound is demonstrated