This specification covers the properties and requirements for round, copper-coated 42 % nickel-iron wire, commonly known as dumet, intended primarily for sealing to soft glass. The wires shall conform to requirements stated for chemical composition, oxide coatings, dimension, internal and surface workmanship, and storage characteristics. Materials shall also undergo tests for thermal expansion, color of coating, diameter, reducible oxides, copper analysis, and metallography.

1.1 This specification covers round, copper-coated 42% nickel-iron wire, commonly known as dumet, intended primarily for sealing to soft glass.

1.2 The values stated in inch-pound units are to be regarded as the standard. The metric equivalents of inch-pound units may be approximate.