Standard Test Method for Coating Weight [Mass] of Metallic Coatings on Steel by X-Ray Fluorescence

Importancia y uso:

5.1 This test method provides a standard method, by the use of X-ray fluorescence (XRF) or isotope measuring instruments, for “on-line” determination of the weight [mass] of coatings on steel sheet produced on continuous production lines, for comparison with specification requirements, and for evaluating conformance of such products to a material specification under the jurisdiction of ASTM Committee A05 and its subcommittees as designated by a purchaser in a purchase order or contract. 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.

5.1.1 This test method determines the coating thickness by repeatedly detecting fluorescent radiation from multiple, defined single spot data points, from which a weight [mass] can be determined, and may be used by other ASTM Committees and other standards writing bodies for the purpose of conformance testing.

5.1.2 The material condition at the time of testing, sampling frequency, specimen location and orientation, reporting requirements, and other test parameters are contained in the pertinent material specification or in a general requirement specification for the particular product form.

5.1.3 A coating of zinc on steel sheet provides protection against corrosion. As the protection is provided by sacrificial loss of zinc, the degree of protection is proportional to the weight [mass] of zinc coating. Specifications for zinc coated steel sheet frequently provide for different designations of coating so that the purchaser can select the coating weight [mass] most suitable for the intended application.

5.2 A reference is provided to the pertinent material specification for the procedures to be used to characterize the coating weight [mass] on production line coils of coated sheet.

Subcomité:

A05.07

Referida por:

A0924_A0924M-22A, A0879_A0879M-22, A0761_A0761M-24, A0918-06R19, A0917-08R20, A0624_A0624M-22, A0626_A0626M-22, A0924_A0924M-22A

Volúmen:

01.06

Número ICS:

17.040.20 (Properties of surfaces)

Palabras clave:

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 ;