METHOD OF MANUFACTURING POTASSIUM NIOBATE SINTERED COMPACT

PROBLEM TO BE SOLVED : To provide a method of manufacturing a potassium niobate sintered compact by which a high density sintered compact is synthesized under atmospheric pressure. SOLUTION : The high density potassium niobate sintered compact provided with excellent piezoelectric characteristic is obtained by passing through processes : wet-mixing niobium oxide, potassium carbonate, a rare earth metal oxide and one kind selected from transition metal oxides and aluminum oxide (a mixing process); a process of calcining the resultant powdery mixture at 600°C to 820°C in the presence of potassium oxide vapor (a 1st calcining process); a process of press-molding the calcined powder and further calcining it at 650°C to 870°C in the presence of potassium oxide vapor (a 2nd calcining process); and a process of pulverizing the obtained calcined material and press-molding the resultant pulverized material and firing it at 1, 020°C to 1, 280°C in the presence of potassium oxide vapor (a main firing process).