GB/T 21931.2 - 2008 stipulates the determination of sulfur content in nickel, ferronickel and nickel alloys by high-frequency combustion infrared absorption method. It describes the determination principle, puts forward requirements for the performance and accuracy of high-frequency combustion furnaces, infrared absorption meters and other equipment, standardizes the selection, preparation and weighing of samples, and details the operation steps of combustion process control and Gas flow rate adjustment. The standard provides a unified method for the production and testing of nickel and related alloys, helping to accurately detect sulfur content, control product mass, and ensure the stable performance of nickel-based materials in various fields.