ASTM B499 Standard test Method for Measuring Coating Thickness by Magnetic Method: Non-magnetic Coatings on Magnetic Metals includes non-destructive measurement of the thickness of non-magnetic coatings on black or other magnetic base metals using a magnetic instrument.
Semnificație și utilizare

5.1 The thickness of the coating is generally important to its performance. For most non-ferrous coatings on steel, the magnetic method is reliable for non-destructively measuring coating thickness and is suitable for specification acceptance testing and SPC/SQC applications.

5.2 This test method should not be used to determine the thickness of electrodeposited nickel coatings on steel. Test method B530 is suitable for this determination.

ASTM B499-2014 Standard Test Method for Magnetic Measurement of Coating Thickness: Non-magnetic Coatings on Magnetic Metals

Etapa 1: Domeniul de aplicare

1.1 This test method includes the non-destructive measurement of the thickness of a non-magnetic coating on a black or other magnetic base metal using a magnetic instrument. It is intended to complement the manufacturer’s instructions on the operation of the instrument, să nu le înlocuiască.

Notă 1 – Nickel-Phosphorus alloys with self-catalytic deposition containing more than 8% phosphorus measured by this test method are sufficiently non-magnetic as long as they are measured prior to any heat treatment.

1.2 These instruments measure the magnetic attraction between the magnet and the base metal, which is affected by the presence of a coating (classified as “magnetic pull off”) or by changes in the magnetic flux density within the probe (classified as “electron”). These instruments cannot distinguish the thickness of individual layers. They can only measure the cumulative thickness of all layers below the probe, down to the base metal.

1.3 Measurements made in accordance with this test method shall comply with the requirements of ISO International Standard 2178, printed in 1982.

1.4 Valorile exprimate în unități SI vor fi considerate standard. Valorile date în paranteze sunt doar pentru referință.

1.5 Acest standard nu este destinat să abordeze toate preocupările legate de siguranță (dacă există) asociat cu utilizarea acestuia. Este responsabilitatea utilizatorilor acestui standard de a stabili practici adecvate de securitate și sănătate și de a determina aplicabilitatea restricțiilor de reglementare înainte de utilizare..