Interference Moire Multiplication And Experimental Investigations Of New Materials By Moire Interferometry

First of all, the current research in moire interferometry is reviewed, in which the wavefront interference theory of moire interferometry is elaborated, and the techniques of grating manufacturing and carrier fringe introduction are summarized. The development prospect of moire interferometry is also predicted. Then, a marvelous combination of moire interferometry, carrier and multiplication technique is proposed for multiplying moire interference fringes, where the displacement fields and the strain fields are involved. By using this multiplication method, the measurement sensitivity of moire interferometry can be increased for more than two times, even for an order of magnitude. The theoretical analyses are given and the demonstrative experiments are conducted successfully.Stress-induced martensitic transformation plastic zone in ceria—stabilized tetragonal zirconia polycrystalline ceramics (Ce—TZP), under loading conditions of uniaxial tension, compression and three—point—bending, are studied by moire interferometry, with use of Raman microprobe spectroscopy and the surface measurement system. The experimental results show that the stress—induced transformation at room temperature is not uniform within the transformation zone and that plastic deformation is concentrated in some narrow band, i.e., macroscopic plastic flow localization proceeds during the initial stage of plastic deformation.Meanwhile, the bending behavior and damage characteristic of carbon fiber aluminium laminates (CALL) hybrid composites are studied by moire interferometry. The results show that the magnitude of the shear strain in carbon fiber / epoxy laminate is clearly larger than that in correspondent aluminium laminate and that the shear strain distribution of carbon fiber/epoxy laminates along the cross-section conforms basically toparabolic distribution curve as same as the shear strain distribution of aluminium laminates along the cross—section. The shear damage either in interlaminations or in carbon fiber / epoxy laminates and the tensile failure of carbon fiber / epoxy laminnate in the tension surface represent the damage forms of the longitudinal and transverse bending specimens, respectively. Finally, a experimental study on pseudoelasticity of Cu—Zn—Al polycrystalline shape memory alloy by moire interferometry is reported. Both the displacement fields and the corresponding pseudoelastic stress strain curves are obtained. The experiment reveals some important features of the deformation process, and a brief discussion is made for the obtained results.