Surface coating weight (thickness) of electrical steel - X-ray spectrometric method
1 Scope
This standard specifies the measurement of surface coating weight (thickness) of electrical steel by the use of X-ray spectrometric method.
The method is used to measure the coating weight per unit area of the specimen at room temperature, and the measurement result may also be expressed by the coating thickness.
This standard is applicable to electrical steel whose surface coating contains stable and undisturbed characteristic elements with high X-ray fluorescence intensity. The measurement range of given coating materials mainly depends on the available characteristic X-ray fluorescence intensity and acceptable measurement uncertainty and varies according to the instruments and measurement methods used.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 16921 Metallic coatings - Measurement of coating thickness - X-ray spectrometric methods
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 16921 and the following apply.
3.1
substrate
material upon which coatings are applied
3.2
surface coating
material coated on electrical steel substrate mainly for insulation protection, including inorganic or semi-organic coating materials such as chromate or phosphate
3.3
intermediate coating
functional material coated between electrical steel substrate and surface coating, with a certain thickness (less than saturation thickness) and playing a certain effect.
If the surface coating is analyzed and tested by scattering method, the intermediate coating may be regarded as a part of the substrate as long as it does not affect the measurement results.
4 Principle
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Measuring method
6 Measuring equipment
7 Influencing factors
8 Measurement procedure
9 Measurement results
10 Measurement uncertainty
11 Test report
Annex A (Informative) Preparation of coating weight standard sample
Annex B (Informative) Calibration of coating weight standard curve
