Comparisons between thermal modeling and experiments: effects of substrate preheating

A three‐dimensional thermal finite element model including the effect of the powder‐to‐solid transition has been developed to investigate the transient temperature distribution and effects of substrate preheating during laser densification of dental powder bed for the layer‐by‐layer fabrication. The model encompasses the effects of the temperature‐ and porosity‐dependent thermal conduction and radiation as well as the temperature‐dependent natural convection. Substrate preheating is found to be important in preventing the formation of cracks in the dental porcelain body during laser densification. The simulation results are found to match the experiments very well.

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