This part specifies the special electrotechnical terms for electric contacts, thermal bimetals, electrothermal alloys, conductive alloys, resistance alloys, thermocouple alloys and magnetic materials. This part is applicable to the formulation of standards for electric contacts, thermal bimetals, electrothermal alloys, conductive alloys, resistance alloys, thermocouple alloys and magnetic materials, preparation of technical documents, preparation and translation of professional manuals, textbooks, monographs and other books, as well as external trade, international technology exchanges, etc.