MEASUREMENT OF THERMAL RESIDUAL STRESS IN THERMAL BARRIER COATING BY MEANS OF PHASE-SHIFT MOIRE INTERFEROMETRY

There are many difficulties in measuring thermal residual stress in thermal barrier coatings,because of their microstructure and microdeformation.Phase-shift moire interferometry is provided which can precisely measure the deformation of solid bodies under various loading conditions.The fundamental theory and experimental technology of the phase-shift moire image-processing technique are introduced.By combining it with relaxation method,a new technique for measuring thermal residual stress is proposed.With the aid of high temperature moire gratings,the distributions of thermal residual stresses in the EB-PVD(electronic beam-physic vapour deposition)coating has been measured,and compared with those other of methods.