ASTM B816-00 (R2021) pdf free download.Standard Specification for Coatings of Cadmium-Zinc Mechanically Deposited.
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 thur thickness classes (see Table I) and several finish types (see Table 2).
1 .2 Toxicin—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 he 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.
5.1.3 Coating type (see 4.2), including required color if Type lIc is used, and required lubricant or organic tinish if Type lId is used,
5.1.4 Nature of the substrate, for example: high-carbon steel, mild steel, coppcr, brass:
5.1.4.1 State if precoating stress relief heat treatment is required and the time and temperature to bc used if different from the standard values (see section 12.1),
5.1.4.2 State if special pretreatments are required to modify the surface of the article (see Note 1),
5.1.4.3 If special cleaning precautions are to be followed (see A1.1). and
5.1.5 Identification of significant surfaces (see 7.4.2).
5.1.6 Requirements and methods of testing one or more of the following:
5.1.6.1 Need for and type of special test specimens (see
5.1.6.2 Appearance (see 7.3),
5.1.6.3 Deposit composition (see 9.2),
5.1.6.4 Thickness (see 9.5),
5.1.6.5 Adhesion (see 9.6),
5.1.6.6 Corrosion resistance (see 9.7),
5.1.6.7 Absence of hydrogen embrittlement, waiting time prior to testing and testing loads (see 9.8), and
5.1.7 The sampling plan to be used (see 8.1) and responsibility for inspection (see section 13. 1).
6. Significance and Use
6.1 corrosion Resistance, General—This functional coating is used to provide corrosion resistance. The performance of this coating depends largely on its thickness and the kind of environment to which it is exposed. Published results of environmental corrosion studies have demonstrated that the coating provides corrosion resistance greater than equivalent thicknesses of zinc coatings in industrial environments and greater corrsion resistance than equivalent thicknesses of cadmium coatings in marine environments.
6.2 Galvanic Corrosion Resistance—The galvanic couple that results in the corrosion of steel and aluminum parts in contact with each other in corrosive environments can also be minimized by plating the steel parts with this mechanically deposited coating.
6.3 Hydrogen Embrittlement, Absence of—The mechanical coating process does not produce any permanent hydrogen embrittlement in products made from high-strength steels, for example, fasteners or lock washers.ASTM B816 pdf download.