VALVE METAL POWDERS AND PROCESS FOR PRODUCING THEM

摘要

A valve metal powder comprising spherical agglomerates, wherein: the D50 value, determined in accordance with ASTM B 822, is 10-80 �m, and the valve metal powder flows freely through a Hall-Flow funnel in accordance with ASTM B 212 or B 417 with a funnel opening diameter of 2/10 inch, and the D90 value, determined in accordance with ASTM B 822 corresponds to at most 1.3 times the D50 value, determined in accordance with ASTM B 822. An anode body produced from the valve metal powder has a bimodal pore distribution, a smaller maximum of the pore distribution corresponding to a primary structure and a larger maximum of the pore distribution corresponding to a secondary structure. The valve metal powder can be used to produce a solid electrolyte capacitor.