GB/T 39696-2020 adopts the standard funnel method for the determination of the flowability of fine ceramic powders. The standard describes the principle of using the standard funnel to let the powder flow freely, and to determine the fluidity by measuring the powder outflow time. Specifies the specifications, materials and other key parameters of the standard funnel, and elaborates the preparation requirements of fine ceramic powder samples, including powder particle size treatment. Clarify the operation points in the test process, such as funnel installation, powder filling and outflow time Measuring method, provide the basis for the unified and accurate determination of the fluidity of fine ceramic powders, and help the research and development of related materials and production quality control.