Time-dependent temperature profiles in dental casting molds were analyzed by an unsteady heat conduction model. The thermal conductivity and initial temperature of the mold greatly affected the heat transfer in the mold. The thermal conductivities of gypsum-and phosphate-bonded investments at high temperatures were accurately measured by means of the hot wire method. From the data obtained, the solidification times of Ag, Ag alloy, and Co-Cr alloy were calculated and compared with the experimental results.
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