标准编号：ISO 21968:2019
中文名称：金属的和非金属基础材料用非磁性金属涂料 涂料厚度测量 状态-敏感逆流法
英文名称：Non-magnetic metallic coatings on metallic and non-metallic basis materials — Measurement of coating thickness — Phase-sensitive eddy-current method
发布日期：2019-09
标准范围
This document specifies a method for using phase-sensitive eddy-current instruments for non-
destructive measurements of the thickness of non-magnetic metallic coatings on metallic and non-
metallic basis materials such as:
a) zinc, cadmium, copper, tin or chromium on steel;
b) copper or silver on composite materials.
The phase-sensitive method can be applied without thickness errors to smaller surface areas and to
stronger surface curvatures than the amplitude-sensitive eddy-current method specified in ISO 2360,
and is less affected by the magnetic properties of the basis material. However, the phase-sensitive
method is more affected by the electrical properties of the coating materials.
In this document, the term “coating” is used for materials such as, for example, paints and varnishes,
electroplated coatings, enamel coatings, plastic coatings, claddings and powder coatings.
This method is particularly applicable to measurements of the thickness of metallic coatings. These
coatings can be non-magnetic metallic coatings on non-conductive, conductive or magnetic base
materials, but also magnetic coatings on non-conductive or conductive base materials.
The measurement of metallic coatings on metallic basis material works only when the product of
conductivity and permeability (σ, μ) of one of the materials is at least a factor of two times the product
of conductivity and permeability for the other material. Non-ferromagnetic materials have a relative
permeability of one.
标准预览图
立即下载标准文件