Abstract:
Thermal sprayed Yttria stabilized Zirconia coatings are fabricated with melted or semi-melted particles solidifying on substrates. This process results in the unique layered, porous and cracked morphology of thermal sprayed ceramic materials. Meanwhile, the stresses within coatings evolve throughout fabrication process. During the actual experiments, the conditions, such as preheat temperature of substrate, raster speed as well as feed rate can influence the stress evolution and residue stress. To quantifying the influences of these associate process conditions, a very detail simulation method of thermal spray is employed in this paper.To exhibit the simulation, nonlinear material properties are to be identified from experiments. First, a suitable stress-strain model is introduced, following by a nonlinear bi-material beam solution. Afterward, an inverse analysis procedure is introduced to process curvature-temperature measurements to extract unknown parameters. With the material properties and input the process condition, a detail simulation is carried out corresponding to the experiments. From the simulation, the temperature at the bottom of substrate and curvature measurements through ICP can be replicated to validate the result of simulation. After the verification of the simulation, the influence of preheated temperature, raster speed and feed rate is studied separately. Moreover, experiments will be implemented to verify these conditions' influence. The stress evolution can reveal the information of coating formation and properties. From the simulation, this becomes very easy and obvious comparing with experiments. Also, the residue stress can be obtained directly from the simulation. In the end, to validate the prediction of simulation, experiments are carried out to compare with the results obtain from simulation
