Welding Rods, Electrodes, and Filler Metals are organized into a two tier system of Specification + Classification.
Welding Filler Metal Specifications group filler metals into similar material types and welding processes. The specification contains many details such as the official classification designators and the testing required to certify the filler metal to that specification.
Within AWS the specification appears as A5.XX
Within ASME the specification appears as SFA5.XX
The following table provides the details for the specifications that apply to the combination of the standard material groupings and the given weld process.
The following chart provides the comprehensive list of the specifications detailed within ASME Section II Part C.
The following is an excerpt from the filler metal portion of a welding procedure (WPS) detailing how the Specification, Classification, F-Number, A-Number, and UNS Number are associated.