GB/T 17721-1999
Metallic coatings--Porosity tests--Ferroxyl test (English Version)
- Standard No.
- GB/T 17721-1999
- Language
- Chinese, Available in English version
- Release Date
- 1999
- Published By
- General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China
- Latest
- GB/T 17721-1999
- Scope
- This standard specifies a test method for measuring the porosity or discontinuity of metallic coatings. During the test, the coating tested did not significantly interact with ferricyanide and chloride ions, and was cathodic to the steel substrate. This method is particularly suitable for engineering chrome coatings. NOTE 1 During the 10 min test period, the sodium chloride solution will dissolve a very thin layer of cover material (see 5.2.3), so that pores obscured by the very thin layer will sometimes be re-exposed. Tests have shown that in actual use this hidden porosity tends to resurface.
GB/T 17721-1999 history
- 1999 GB/T 17721-1999 Metallic coatings--Porosity tests--Ferroxyl test
