ASTM F1941-10 - 1.12.2007
 
1. Scope

1.1 This specification covers application, performance and dimensional requirements for electrodeposited coatings on threaded fasteners with unified inch screw threads. It specifies coating thickness, supplementary hexavalent chromate or trivalent chromite finishes, corrosion resistance, precautions for managing the risk of hydrogen embrittlement and hydrogen embrittlement relief for high-strength and surface-hardened fasteners. It also highlights the differences between barrel and rack plating and makes recommendations as to the applicability of each process.

1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.3 The following precautionary statement pertains to the test method portion only, Section 9, of this specification: 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 and health practices and determine the applicability of regulatory limitations prior to use.

 
2. Referenced Documents

E376-19

Standard Practice for Measuring Coating Thickness by Magnetic-Field or Eddy Current (Electromagnetic) Testing Methods

F606-14

Standard Test Methods for Determining the Mechanical Properties of Externally and Internally Threaded Fasteners, Washers, Direct Tension Indicators, and Rivets

F1470-24

Standard Practice for Fastener Sampling for Specified Mechanical Properties and Performance Inspection

F1624-12(2018)

Standard Test Method for Measurement of Hydrogen Embrittlement Threshold in Steel by the Incremental Step Loading Technique

F1940-07a(2019)

Standard Test Method for Process Control Verification to Prevent Hydrogen Embrittlement in Plated or Coated Fasteners (Includes all amendments and changes 9/17/2019).

B1.1

Unified Inch Screw Threads (UN and UNR Thread Form)

IFI-142

Hydrogen Embrittlement Risk Management

D6492-99(2022)

Standard Practice for Detection of Hexavalent Chromium On Zinc and Zinc/Aluminum Alloy Coated Steel

NASM-1312-5

Fast Test Method - Method 5: Stress Durability

B487-20

Standard Test Method for Measurement of Metal and Oxide Coating Thickness by Microscopical Examination of Cross Section

B499-09(2021)e1

Standard Test Method for Measurement of Coating Thicknesses by the Magnetic Method: Nonmagnetic Coatings on Magnetic Basis Metals (Includes all amendments and changes 5/18/2021).

B117-19

Standard Practice for Operating Salt Spray (Fog) Apparatus

B504-90(2023)

Standard Test Method for Measurement of Thickness of Metallic Coatings by the Coulometric Method

B567-98(2021)

Standard Test Method for Measurement of Coating Thickness by the Beta Backscatter Method

B568-98(2021)

Standard Test Method for Measurement of Coating Thickness by X-Ray Spectrometry

B659-90(2021)

Standard Guide for Measuring Thickness of Metallic and Inorganic Coatings