1. Arc spray gun method
Use a micrometer to measure the diameter of the tungsten wire, and use the instrument and device of the arc spray gun to adjust and measure the speed of the wire feeding, the melting current and the voltage between the two tungsten wire electrodes. The effects of tungsten wire diameter, wire feeding speed and inter-electrode voltage on working current, powder spraying effect and powder quality were studied. The spherical tungsten powder obtained by this method has a wide particle size distribution, and the coarse powder can be used to make filters, and the fine powder can be used to make a porous tungsten ionizer. At the same time, the method has the advantages of simple and easy to obtain equipment and low cost, but the production efficiency is low, which is not conducive to industrialized production.

2. Microwave single-film cavity method
The tungsten powder is put into a quartz glass tube, and heat-treated in a single-cavity sintering furnace under the action of microwaves to spheroidize the tungsten powder. The results show that the spheroidization of the original polyhedral tungsten powder can be observed after treating the FW-1 tungsten powder for different time when the microwave power is 450-1000w. Because the particle size of w powder is basically the same, the total surface area is large, the particle size is small, and there is enough input depth for microwaves, and the mutual heating is very uniform. With the increase of heating power and temperature, the surface diffusion of tungsten powder is more intense, and the degree of spheroidization of the obtained tungsten powder is higher. Therefore, increasing the power and prolonging the treatment time will help the spheroidization of the tungsten powder.