Microwave plasma spheroidizing device and method for micron-sized powder

The invention relates to a microwave plasma spheroidizing device and method for micron-sized powder, and the device comprises a plasma exciter which comprises an inner conductor tube; a quartz tube is sleeved in the waveguide tube, and the lower end of the inner conductor tube is positioned below the quartz tube; the reaction chamber is positioned below the plasma exciter; the back-blowing gas direction of the back-blowing pipe is from bottom to top, and the upper end of the back-blowing pipe right faces the microwave plasma torch and is located below the microwave plasma torch. The end part of the lower end of the inner conductor tube is arranged below the quartz tube, so that powder is far away from the quartz tube during spheroidizing, the wall pasting problem of the quartz tube is avoided, and the spheroidizing rate is improved. The retention time of the spheroidized powder in the reaction chamber is prolonged by arranging the reverse blowing pipe, so that the refractory irregular powder is uniformly sphe