Influence of Heat Treatment Conditions of Calcium-thermal Tantalum Powders on the Characteristics of Capacitor Anodes

The results of investigation of the influence of various methods of heat treatment of primary calcium-thermal tantalum powders on the characteristics of capacitor anodes are presented. Heat treatment of powder with specific surface area of 8.6 m/g in the temperature range of 900–1300 °C followed by deoxidation with magnesium vapor allowed to obtain capacitor powders with specific charge from 30000 to 80000 μC/g. As a result of powder heat treatment such characteristics of anodes as sintering shrinkage, powder specific surface utilization factor (increased from 4 to 20% at anodization up to 30 V) were improved. Specific charge losses at increasing the anodizing voltage from 16 to 40 V decreased from 80 to 25%.