| 摘要 |
PROBLEM TO BE SOLVED: To obtain high density dielectric porcelain fired at a low temp. and having high Qu in a microwave domain and a low absolute value of πt by calcining and pulverizing a starting material prepd. by adding Y2 O3 to a specified compsn., adding glass powder to the resultant calcined powder, compacting and firing them. SOLUTION: Starting material prepd. by adding 0.5-15 pts.wt. Y2 O3 to 100 pts.wt. compsn. represented by the formula xBaO∼yNd2 O3 .zTiO2 (where x+y+ z=100mol%, 8.5<=x<=20, 5<=y<=23 and 62<=z<=85) is calcined at 900-1,200 deg.C and pulverized to form calcined powder. A mixture of 99-85wt.% of the calcined powder with 1-15wt.% glass powder having <=450 deg.C transition temp. is compacted and fired at 850-1,000 deg.C to obtain the objective dielectric porcelain having <=1% rate of water absorption, 1,200-1,700GHz product of no-load Q and frequency at which the no-load Q is measured and +20 to -20ppm/ deg.C temp. coefft. of resonance frequency. |
