ASTM B984-12(2020)e1
Standard Specification for Electrodeposited Coatings of Palladium-Cobalt Alloy for Engineering Use

Standard No.

ASTM B984-12(2020)e1

Release Date

2020

Published By

American Society for Testing and Materials (ASTM)

Latest

ASTM B984-12(2020)e1

Scope

1.1 This specification covers requirements for electrodeposited palladium-cobalt alloy coatings containing approximately 80 % of palladium and 20 % of cobalt. Composite coatings consisting of palladium-cobalt with a thin gold overplate for applications involving electrical contacts are also covered. Palladium and palladium-cobalt remain competitive finishes for high reliability applications. 1.2 Properties—Palladium is the lightest and least noble of the platinum group metals (1)2 . It has the density of 12 gm per cubic centimeter, specific gravity of 12.0, that is substantially lower than the density of gold, 19.29 gm per cubic centimeter, specific gravity 19.3, and platinum 21.48 gm per cubic centimeter, specific gravity 21.5. The density of cobalt on the other hand is even less than palladium. It is only 8.69 gm per cubic centimeter, specific gravity 8.7. This yields a greater volume or thickness of coating and, consequently, some saving of metal weight and reduced cost. Palladium-cobalt coated surfaces provide a hard surface finish (Test Methods E18), thus decreasing wear and increasing durability. Palladium-cobalt coated surfaces also have a very low coefficient of friction 0.43 compared to hard gold 0.60, thus providing lower mating and unmating forces for electrical contacts (1). Palladium-cobalt has smaller grain size (Test Methods E112), 50 – 150 Angstroms, compared to Hard Gold 200 – 250 Angstroms (1), or 5 – 15 nanometer, compared to hard gold 20 – 25 nanometer (1). Palladium-cobalt has low porosity (Test Method B799) 0.2 porosity index compared to hard gold 3.7 porosity index (1). Palladium-cobalt coated surfaces have high ductility (Practice B489) 3-7 % compared to that of hard gold <3 % (1). The palladium-cobalt coated surface is also thermally more stable 395 °C than hard gold 150 °C, and silver 170 °C. The following Table 1 compares the hardness range of electrodeposited palladium-cobalt with other electrodeposited noble metals and alloys (2, 3). TABLE 1 Hardness of Noble Metals Approximate Hardness (HK25) Gold 50–250 Palladium 75–600 Platinum 150–550 Palladium-Nickel 300–650 Palladium-Cobalt 500–650 Rhodium 750–1100 Ruthenium 600–1300 1.3 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.5 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 B984-12(2020)e1 Referenced Document

• ASTM B183 Standard Practice for Preparation of Low-Carbon Steel for Electroplating
• ASTM B242 Standard Guide for Preparation of High-Carbon Steel for Electroplating*， 2020-11-01 Update
• ASTM B254 Standard Practice for Preparation of and Electroplating on Stainless Steel*， 2020-11-01 Update
• ASTM B281 Standard Practice for Preparation of Copper and Copper-Base Alloys for Electroplating and Conversion Coatings
• ASTM B322 Standard Guide for Cleaning Metals Prior to Electroplating*， 2020-11-01 Update
• ASTM B343 Standard Practice for Preparation of Nickel for Electroplating with Nickel*， 2020-11-01 Update
• ASTM B374 Standard Terminology Relating to Electroplating
• ASTM B481 Standard Practice for Preparation of Titanium and Titanium Alloys for Electroplating
• ASTM B482 Standard Practice for Preparation of Tungsten and Tungsten Alloys for Electroplating
• ASTM B487 Standard Test Method for Measurement of Metal and Oxide Coating Thickness by Microscopical Examination of Cross Section
• ASTM B488 Standard Specification for Electrodeposited Coatings of Gold for Engineering Uses
• ASTM B489 Standard Practice for Bend Test for Ductility of Electrodeposited and Autocatalytically Deposited Metal Coatings on Metals*， 2023-05-01 Update
• ASTM B499 Standard Test Method for Measurement of Coating Thicknesses by the Magnetic Method: Nonmagnetic Coatings on Magnetic Basis Metals
• ASTM B507 Standard Practice for Design of Articles to Be Electroplated on Racks
• ASTM B542 Standard Terminology Relating to Electrical Contacts and Their Use
• 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*， 2024-04-21 Update
• ASTM B568 Standard Test Method for Measurement of Coating Thickness by X-Ray Spectrometry*， 2021-04-01 Update
• 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 B679 Standard Specification for Electrodeposited Coatings of Palladium for Engineering Use*， 2021-10-01 Update
• ASTM B689 Standard Specification for Electroplated Engineering Nickel Coatings*， 2023-05-01 Update
• ASTM B697 Standard Guide for Selection of Sampling Plans for Inspection of Electrodeposited Metallic and Inorganic Coatings*， 2021-10-01 Update
• ASTM B741 Standard Test Method for Porosity In Gold Coatings On Metal Substrates By Paper Electrography
• ASTM B748 Standard Test Method for Measurement of Thickness of Metallic Coatings by Measurement of Cross Section with a Scanning Electron Microscope*， 2021-10-01 Update
• ASTM B762 Standard Test Method of Variables Sampling of Metallic and Inorganic Coatings
• ASTM B765 Standard Guide for Selection of Porosity Tests for Electrodeposits and Related Metallic Coatings
• ASTM B799 Standard Test Method for Porosity in Gold and Palladium Coatings by Sulfurous Acid/Sulfur-Dioxide Vapor
• ASTM B809 Standard Test Method for Porosity in Metallic Coatings by Humid Sulfur Vapor ("Flowers-of-Sulfur")*， 2024-04-21 Update
• ASTM D1125 Standard Test Methods for Electrical Conductivity and Resistivity of Water
• ASTM D3951 Standard Practice for Commercial Packaging
• ASTM E112 Standard Test Methods for Determining Average Grain Size
• ASTM E18 Standard Test Methods for Rockwell Hardness of Metallic Materials*， 2022-05-01 Update

ASTM B984-12(2020)e1 history

• 2020 ASTM B984-12(2020)e1 Standard Specification for Electrodeposited Coatings of Palladium-Cobalt Alloy for Engineering Use
• 2012 ASTM B984-12 Standard Specification for Electrodeposited Coatings of Palladium- Cobalt Alloy for Engineering Use