1. Scope

1.1 This guide outlines a general method for determining the mass per unit area of electrodeposited, electroless, mechanically-deposited, vacuum-deposited, anodicoxide, and chemical conversion coatings by gravimetric and other chemical analysis procedures.

1.2 This guide determines the average mass per unit area over a measured area.

1.3 The stripping methods cited are described in specifications or in the open literature or have been used routinely by at least one laboratory.

1.4 The procedures outlined can be used for many coating-substrate combinations. They cannot be used where the coating cannot be separated from the substrate by chemical or physical means as would be the case if white brass were plated with yellow brass.

1.5 In principle, these procedures can be used to measure very thin coatings or to measure coatings over small areas, but not thin coatings over small areas. The limits depend on the required accuracy. For example, 2.5 mg/cm of coating might require 2.5 mg of coating covering 1 cm , but 0.1 mg/cm of coating would require 25 cm to obtain 2.5 mg of coating.

1.6 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems 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 (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

A90/A90M Test Method for Weight [Mass] of Coating on Iron and Steel Articles with Zinc or Zinc-Alloy Coatings

A309 Test Method for Weight and Composition of Coating on Terne Sheet by the Triple-Spot Test

A428/A428M Test Method for Weight [Mass] of Coating on Aluminum-Coated Iron or Steel Articles

B137 Test Method for Measurement of Coating Mass Per Unit Area on Anodically Coated Aluminum

B449 Specification for Chromates on Aluminum

British Standards Institution Documents

Keywords

Acceptance criteria/testing--coatings; Aluminum coatings; Anodic coatings; Average mass per unit area; Brass electrodeposition; Cadmium metals (coating/plating); Chemical analysis; Chromate coatings; Chromium electroplating; Coating thickness; Density--metallic coatings; Electrodeposited coatings; Electrodeposited Cu coatings; Electrodeposited gold coatings; Gravimetric determination; Lead metals/alloys; Lead-tin alloys/coatings; Linear changes/linearity; Mass per unit area; Mechanically deposited coatings; Micrometer measurement; Microroughness; Microscopic examination--metallic/inorganic coatings; Nickel coatings; Phosphate coatings; Planimetric procedure; Silver (electrodeposited); Terne plate; Tin metals/alloys--electrodeposited coatings; Vernier caliper; Weight per unit area;

ICS Code

ICS Number Code 25.220.40 (Metallic coatings)

DOI: 10.1520/B0767-88R01

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