Abstract

This test method covers the use of X-ray fluorescence (XRF) for determining the coating weight (mass) of metallic coatings on steel sheets. This test method is intended to be used for on-line measurements of coatings on continuous production and is applicable to coatings such as tin mill products, zinc or zinc iron coatings, aluminum zinc-coating, zinc-aluminum coating, and zinc-nickel coating. This test method may be applicable to other coatings, provided that the elemental nature of the coating and substrate are compatible with the technical aspects of XRF such as the absorption coefficient of the system, primary radiation, fluorescent radiation, and type of detection. The test method includes the procedure for developing a single standard determination of coating weight (mass) and the procedures for both X-ray tube and isotope coating weight (mass) measuring instruments. The basic principle of the measurement by XRF method and the factors affecting accuracy and precision including equipment, data collection, and calibration of the instrument are detailed. The instrument shall be operated in a manner that meets the requirements specified for single data point definition, area of fluorescence, transverse scan speed, dwell time, and coating weight (mass) sampling width and location. The standard test condition and test locations across the strip width are illustrated.

This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.

1. Scope

1.1 This test method covers the use of X-ray fluorescence (XRF) for determining the coating weight (mass) of metallic coatings on steel sheet. The test method is intended to be used for on-line measurements of coating on continuous production lines.

1.2 This test method is applicable to the coatings covered by the following ASTM specifications: A599/A599M , A623 , A623M , A653/A653M , A792/A792M , A875/A875M , A879/A879M , A918 , A924/A924M , A1046/A1046M , and A1063/A1063M . It may be applicable to other coatings, providing that the elemental nature of the coating and substrate are compatible with the technical aspects of XRF such as the absorption coefficient of the system, primary radiation, fluorescent radiation, type of detection.

1.3 This test method includes the procedure for developing a single standard determination of coating weight (mass).

1.4 This test method includes procedures for both X-ray tube and isotope coating weight (mass) measuring instruments.

1.5 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.

1.6 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 (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

A599/A599M Specification for Tin Mill Products, Electrolytic Tin-Coated, Cold-Rolled Sheet

A623 Specification for Tin Mill Products, General Requirements

A623M Specification for Tin Mill Products, General Requirements [Metric]

A653/A653M Specification for Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed) by the Hot-Dip Process

A792/A792M Specification for Steel Sheet, 55 % Aluminum-Zinc Alloy-Coated by the Hot-Dip Process

A875/A875M Specification for Steel Sheet, Zinc-5 % Aluminum Alloy-Coated by the Hot-Dip Process

A879/A879M Specification for Steel Sheet, Zinc Coated by the Electrolytic Process for Applications Requiring Designation of the Coating Mass on Each Surface

A902 Terminology Relating to Metallic Coated Steel Products

A918 Specification for Steel Sheet, Zinc-Nickel Alloy Coated by the Electrolytic Process for Applications Requiring Designation of the Coating Mass on Each Surface

A924/A924M Specification for General Requirements for Steel Sheet, Metallic-Coated by the Hot-Dip Process

A1046/A1046M Specification for Steel Sheet, Zinc-Aluminum-Magnesium Alloy-Coated by the Hot-Dip Process

A1063/A1063M Specification for Steel Sheet, Twin-Roll Cast, Zinc-Coated (Galvanized) by the Hot-Dip Process

Keywords

aluminum zinc-coating; coating; coating weight (mass); coatings-metallic; metallic coated; sheet; steel sheet; tin mill products; X-ray fluorescence; zinc coating; zinc-5 % aluminum coating: Aluminum coatings; Coating weight; Electrodeposited coatings; Mass; Mechanically deposited coatings; Metallic-coated steel materials; Spectroscopy--X-ray fluorescence (XRF); Steel--mechanically deposited coatings; Steel wire (coated); Tin mill products (coating thickness); XRF (X-ray fluorescence)--metals/alloys; Zinc-aluminum (ZA) coatings; Zinc-coated steel sheet; Zinc coatings;

ICS Code

ICS Number Code 17.040.20 (Properties of surfaces)

DOI: 10.1520/A0754_A0754M-11

ASTM International is a member of CrossRef.

ASTM A754 / A754M