The tantalum core manufacturing process of high temperature full tantalum capacitor belongs to the field of capacitors, and the invention solves the problems existing in the existing manufacturing process of high temperature full tantalum capacitor tantalum core. The invention has two technical schemes. The first technical solution steps: Step 1, select the tantalum core molding die, the lower punch die of the molding die using a convex die with a circular edge of 45°; Step 2. Use alcohol demoulding to make tantalum core rough; Step 3. Make a hook out of the upper end of the tantalum wire of the finished raw tantalum core, hang it on the tantalum wire mesh, and place it in the tantalum tube for suspension and sintering to make tantalum core. The second technical solution steps: Step 1, select the tantalum core molding die, the lower punch of the molding die using a convex die with a circular edge of 45° convex chamfering; Step 2. Use alcohol demoulding to make tantalum core rough; Step 3. Place the made raw tantalum core on the tantalum plate and place it in the tantalum cylinder for sintering to make tantalum core.
Tantalum core is an important component of high temperature tantalum capacitors, and the quality of tantalum core determines the quality of high temperature tantalum capacitors. Therefore, the manufacturing process of tantalum core has attracted much attention.
The existing tantalum core molding is roughly divided into two ways for demounding: ① unmixed powder molding: tantalum powder does not mix with any impurities, and is directly pressed. The method does not introduce impurities and contaminate the tantalum core. However, due to the lack of lubrication and high friction force, the tantalum powder particles tilt in the direction of the force during demolding, and the surface pores are reduced. (2) Mixed with adhesive forming: tantalum powder mixed with stearic acid or camphor and other solid adhesive, and then pressed forming. Solid adhesive can play a good role in lubrication and retain the surface pores well, but the mixed adhesive is difficult to remove, and the residual carbon element will react with tantalum during sintering, polluting the tantalum core.
The edge of the existing tantalum core molding mold is right Angle, and the sharp right Angle edge of the formed tantalum core will scratch the edge of the bottom pad, and there will be a gap when the tantalum core on the right Angle is matched with the bottom pad. If the tantalum core on the right Angle is not closely matched with the structural pad, the vibration resistance and quality of the high-temperature tantalum capacitor will be reduced. In the process of sintering at high temperature and constant temperature, the tantalum powder particles will melt with each other, and the volume will be reduced after cooling. The existing tantalum core is placed on the tantalum plate during sintering. Under the influence of gravity and the adhesion between the bottom of tantalum core and the sintered tantalum plate, tantalum powder accumulation will be formed at the bottom of tantalum core, and the bottom hardly shrinks.
