NICKEL BASED ULTRAFINE POWDER

摘要

For reducing the volume of laminated ceramic capacitor by decreasing the dielectric thickness to 1 mum or less and for increasing the number of dielectrics and electrodes laminated for capacity increase, the amount of coarse grains exceeding 1 mum in metal powder for use in the internal electrodes is reduced. In particular, a nickel based ultrafine powder wherein the average diameter of primary grains is in the range of 0.05 to 0.3 mum and wherein the ratio of the number of grains of 1 mum or greater primary grain diameter to the total number of grains is 50 ppm or less while the ratio of the number of grains with diameter of not above 0.6-fold of the average grain diameter to the total number of grains is 10% or less. This nickel based ultrafine powder can be produced from nickel chloride vapor, etc. by vapor phase hydrogen reduction process.