Abstract
In order to measure the density of higher-melting dental metals in a wide temperature range from room temperature to about 1700℃, the previous apparatus based on the sessile drop method was advanced. By using a graphite heater, the furnace was able to meet the demand for measurements at high temperatures. By completing the optical system, the sharp shadow of the sample was taken on film even at high temperatures at which the sample radiates intensely. A texture analyzing system was composed by combining a projector through a digitizer to a microcomputer and errors caused by analyzing were discussed. The systematic error of the analyzing system was given less than 0.08%. The density of pure nickel was determined with the apparatus and the analyzing system, and the satisfactory results were obtained. Namely, the apparatus and the analyzing system were proved to be very useful to investigate the thermal shrinkage of higer-melting dental metals.
