This specification covers the requirements for cadmium-zinc coatings deposited on metallic products by mechanical deposition. The coating shall be classified in four thickness classes namely, Class 7, Class 12, Class 25, and Class 50. The coating shall also be classified according to coating types defined as Type I, Type IIa, Type IIb, Type IIc, and Type IId. The materials shall be subjected to the following test methods: coating composition determination; thickness measurement; adhesion test; corrosion resistance test; appearance test; and hydrogen embrittlement test.

1.1 General—This specification covers the requirements for a coating that is a mixture of cadmium and zinc deposited on metallic products by mechanical deposition. The coating is provided in four thickness classes (see Table 1) and several finish types (see Table 2).

1.2 Toxicity—Warning: Cadmium is toxic; therefore these coatings should not be used on articles that will contact food or beverages, or for dental and other equipment that may be inserted into the mouth. Also, the coatings should not be used on articles that will be heated to high temperatures, because cadmium will form toxic fumes. Similarly, if coated articles are welded, soldered, or otherwise heated during fabrication, adequate ventilation should be provided to exhaust toxic fumes.

1.3 Similar Documents—Other kinds of mechanically deposited coatings are covered by Specifications B635, B695, and B696.

1.4 The following precautionary caveat pertains only to the test method portion, Section 9, of this specification. This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.