In this paper, the effects of the material properties and their variations on the temperature distribution and thermal stress field, which have determining roles on the final qualities of a part fabricated using laser solid freeform fabrication process, are studied. This is achieved by numerical and experimental fabrications of a thin wall of two Stellite 6 layers and two Ti layers on a SS304L substrate. A 3D time-dependent numerical approach is used to simulate the process. Using this model, the geometry of the additive material in a layer-by-layer fashion as well as temperature distribution and thermal stress field are dynamically obtained throughout the process domain The experimental and numerical results are used to characterize the build-up and also identify an optimum laser power for each layer deposition in order to reduce the thermal stresses.
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