GB/T 41079.3-2024 "Method for determination of physical properties of liquid metals, Part 3: Determination of viscosity" specifies the Measuring method for the apparent viscosity of liquid metals. The swirl/spin method is used to measure the rheological characteristics of liquid metals at a specific shear rate by swirl/spin Viscosity meter. This method is suitable for liquid metals in the range of room temperature to 200 ° C. The determination process requires the use of inert protective gas to prevent oxidation. The standard specifies the test temperature, the selection of shear rate, Sample Handling and data processing methods, and provides the calibration requirements of the measurement system. The results are expressed in terms of apparent viscosity and require precision to meet a specific standard. This standard is suitable for the analysis of rheological performance of liquid metals and is widely used in the research and industrial applications of liquid metals in the fields of thermal control, energy, electronics, etc.