The invention provides a
microwave sintering method for PTC ceramics, and belongs to the technical field of electronic
ceramic manufacturing process. In order to solve the problem that the PTC material has poor
microwave absorbing property at a lower temperature, the method designs an assistant heating device, and the device can effectively improve the problem that the PTC green blank has low
microwave absorbing efficiency at the temperature below 500 DEG C. In order to solve the problems that the PTC is heated unevenly and is easy to crack, the method designs an automatic rotating device with adjustable speed, and the rotating speed of the device is 5 to 30
revolutions per minute. The method provides a low-temperature insulation
sintering process for the PTC: raising the temperature at the speed of 300 to 600 DEG C per hour from the
room temperature to 500 DEG C, preserving the heat for 1 hour at 500 DEG C, then raising the temperature at the speed of 500 to 800 DEG C per hour, preserving the heat for 10 to 30 minutes with the high temperature of 1,200 to 1,250 DEG C, and then reducing the temperature to 1,100 DEG C at the speed of 500 to 600 DEG C per hour, and preserving the heat for 10 to 30 minutes at low temperature. The method also provides a process for previously removing glue in a common furnace and then carrying out
microwave sintering. In order to avoid the problems that the
temperature measurement for a thermoelectric couple is easily interfered under the microwave condition and has large error, the method adopts an
infrared temperature gauge to measure the temperature. By using the method, the
sintering time can be shortened, the sintering temperature can be reduced, and the electrical energy is greatly saved; and the performance of a product is superior to the performance of the product produced by the prior sintering method.