Abstract: An alloy material includes: a composition containing 17 at % to 25 at % of silver (Ag), 30 at % to 45 at % of palladium (Pd), and 30 at % to 53 at % of copper (Cu) in a composition range of a ternary alloy of Ag, Pd, and Cu; and at least one of manganese (Mn), tin (Sn), silicon (Si), antimony (Sb), titanium (Ti) and magnesium (Mg) added to the composition in a range of 4.5 at % or less, and the Mn in a range of 0.5 at % to 3.5 at %, the Sn in a range of 1 at % to 2 at %, the Si in a range of 0.5 at % to 2 at %, the Sb in a range of 0.5 at % to 3 at %, the Ti in a range of 0.5 at % to 2 at %, and the Mg in a range of 0.5 at % to 3.5 at % are added to the composition.

Abstract: An alloy material includes: a composition containing 17 at % to 25 at % of silver (Ag), 30 at % to 45 at % of palladium (Pd), and 30 at % to 53 at % of copper (Cu) in a composition range of a ternary alloy of Ag, Pd, and Cu; and at least one of manganese (Mn), tin (Sn), silicon (Si), antimony (Sb), titanium (Ti) and magnesium (Mg) added to the composition in a range of 4.5 at % or less, and the Mn in a range of 0.5 at % to 3.5 at %, the Sn in a range of 1 at % to 2 at %, the Si in a range of 0.5 at % to 2 at %, the Sb in a range of 0.5 at % to 3 at %, the Ti in a range of 0.5 at % to 2 at %, and the Mg in a range of 0.5 at % to 3.5 at % are added to the composition.

Abstract: A method for manufacturing noble metal fine particles, by which noble metal fine particles are obtained whose particle diameter and alloy composition are easy to control and whose crystallinity and purity are high, is provided. The method includes the steps of: (1) obtaining a molten mixture containing a noble metal chloride, by insufflating chlorine gas into a mixture of a molten salt of an alkali metal chloride and a noble metal; (2) obtaining a noble metal oxide as a precipitate by adding an alkali metal carbonate to the molten mixture under an inert gas atmosphere; (3) obtaining a mixture containing noble metal oxide fine particles, by pulverizing the noble metal oxide with at least one of an alkali metal carbonate and an alkali earth metal carbonate; and (4) obtaining noble metal fine particles by heating the mixture obtained in step (3) under an atmosphere of gas containing hydrogen, and then treating the heat-treated mixture with acid.

Abstract: The present invention provides a method for preparing a glass-ceramic containing leucite crystals, comprising the steps of: mixing (1) a glassy material comprising 53 to 65 wt. % of SiO2, 13 to 23 wt. % of Al2O3, 9 to 20 wt. % of K2O and 6 to 12 wt. % of Na2O and (2) synthetic leucite seed crystals comprising 53 to 64 wt. % of SiO2, 19 to 27 wt. % of Al2O3 and 17 to 25 wt. % of K2O, and heat-treating the mixture at 750 to 950° C. for 1 to 5 hours; and a dental porcelain powder and a metal-ceramic restoration both comprising a glass-ceramic prepared by the method. The porcelain comprising the glass-ceramic prepared by the method is substantially free of opacification and decrease in the coefficient of thermal expansion, during fusion-bonding to a metal frame.