ASTM B766-23
Standard Specification for Electrodeposited Coatings of Cadmium

Standard No.

ASTM B766-23

Release Date

2023

Published By

American Society for Testing and Materials (ASTM)

Latest

ASTM B766-23

Scope

1.1  This specification covers the requirements for electrodeposited cadmium coatings on products of iron, steel, and other metals. Note 1:  Cadmium is deposited as a coating principally on iron and steel products. It can also be electrodeposited on aluminum, brass, beryllium copper, copper, nickel, and powder metallurgy parts. 1.2  The coating is provided in various thicknesses up to and including 25 μm either as electrodeposited or with supplementary finishes. 1.3  Cadmium coatings are used for corrosion resistance and for corrosion prevention of the basis metal part. The as-deposited coating (Type I) is useful for the lowest cost protection in a mild or noncorrosive environment where early formation of white corrosion products is not detrimental or harmful to the function of a component. The prime purpose of the supplementary chromate finishes (Types II and III) on the electroplated cadmium is to increase corrosion resistance. Chromating will retard or prevent the formation of white corrosion products on surfaces exposed to various environmental conditions as well as delay the appearance of corrosion from the basis metal. 1.4  Cadmium plating is used to minimize bi-metallic corrosion between high-strength steel fasteners and aluminum in the aerospace industry. Undercutting of threads on fastener parts is not necessary as the cadmium coating has a low coefficient of friction that reduces the tightening torque required and allows repetitive dismantling. 1.5  Cadmium-coated parts can easily be soldered without the use of corrosive fluxes. Cadmium-coated steel parts have a lower electrical contact resistance than zinc-coated steel. The lubricity of cadmium plating is used on springs for doors and latches and for weaving machinery operating in high humidity. Corrosion products formed on cadmium are tightly adherent. Unlike zinc, cadmium does not build up voluminous corrosion products on the surface. This allows for proper functioning during corrosive exposure of moving parts, threaded assemblies, valves, and delicate mechanisms without jamming with debris. 1.6  This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ASTM B766-23 Referenced Document

• ASTM A165 Specification for Electrodeposited Coatings of Cadmium on Steel
• ASTM B117 Standard Practice for Operating Salt Spray (Fog) Apparatus
• ASTM B183 Standard Practice for Preparation of Low-Carbon Steel for Electroplating
• ASTM B201 Standard Practice for Testing Chromate Coatings on Zinc and Cadmium Surfaces
• ASTM B242 Standard Guide for Preparation of High-Carbon Steel for Electroplating
• ASTM B253 Standard Guide for Preparation of Aluminum Alloys for Electroplating
• ASTM B254 Standard Practice for Preparation of and Electroplating on Stainless Steel
• ASTM B281 Standard Practice for Preparation of Copper and Copper-Base Alloys for Electroplating and Conversion Coatings
• ASTM B320 Standard Practice for Preparation of Iron Castings for Electroplating
• ASTM B322 Standard Guide for Cleaning Metals Prior to Electroplating
• ASTM B343 Standard Practice for Preparation of Nickel for Electroplating with Nickel
• ASTM B374 Standard Terminology Relating to Electroplating
• ASTM B487 Standard Test Method for Measurement of Metal and Oxide Coating Thickness by Microscopical Examination of Cross Section
• ASTM B499 Standard Test Method for Measurement of Coating Thicknesses by the Magnetic Method: Nonmagnetic Coatings on Magnetic Basis Metals
• ASTM B504 Standard Test Method for Measurement of Thickness of Metallic Coatings by the Coulometric Method
• ASTM B507 Standard Practice for Design of Articles to Be Electroplated on Racks
• ASTM B558 Standard Practice for Preparation of Nickel Alloys for Electroplating
• ASTM B567 Standard Test Method for Measurement of Coating Thickness by the Beta Backscatter Method*， 2024-04-22 Update
• ASTM B568 Standard Test Method for Measurement of Coating Thickness by X-Ray Spectrometry
• ASTM B571 Standard Practice for Qualitative Adhesion Testing of Metallic Coatings
• ASTM B602 Standard Test Method for Attribute Sampling of Metallic and Inorganic Coatings
• ASTM B697 Standard Guide for Selection of Sampling Plans for Inspection of Electrodeposited Metallic and Inorganic Coatings
• ASTM B849 Standard Specification for Pre-Treatments of Iron or Steel for Reducing Risk of Hydrogen Embrittlement
• ASTM B850 Standard Guide for Post-Coating Treatments of Steel for Reducing the Risk of Hydrogen Embrittlement
• ASTM E8 Standard Test Methods for Tension Testing of Metallic Materials
• ASTM F519 Standard Test Method for Mechanical Hydrogen Embrittlement Evaluation of Plating Processes and Service Environments
• ISO 2082 Metallic and other inorganic coatings — Electroplated coatings of cadmium with supplementary treatments on iron or steel

ASTM B766-23 history

• 2023 ASTM B766-23 Standard Specification for Electrodeposited Coatings of Cadmium
• 1986 ASTM B766-86(2015) Standard Specification for Electrodeposited Coatings of Cadmium
• 1986 ASTM B766-86(2008) Standard Specification for Electrodeposited Coatings of Cadmium
• 1986 ASTM B766-86(2003) Standard Specification for Electrodeposited Coatings of Cadmium
• 1998 ASTM B766-86(1998) Standard Specification for Electrodeposited Coatings of Cadmium