Scope:

ASTM E252 standard test covers the procedure to estimate the thickness of metallic foils and thin sheets. It can be used for measuring a thickness of 0.015 inches (0.35 mm) and less. This method is applicable to a wide range of films, foils, or sheets.

Test procedure:

In ASTM E252, the blank determination is done for 8.000 ± 0.008 inch²representative of the foil or sheet for which the thickness is to be determined. The surface of the specimen is cleaned using a suitable solvent (such as acetone) to ensure that the surface is free of soil or any other contaminant. The mass of the clean, dry specimen is determined to the nearest 0.1 mg. The thickness of the foil or sheet is then evaluated using the density and mass obtained from the above-mentioned procedure. 

Video 01: Method to measure the thickness of an aluminum foil

Specimen size:

Specimens ranging in size from 8 to 32 inch² are convenient to handle. The area of the specimen under the ASTM E252 test should be known and controlled to an accuracy of ± 0.1%.

Data:

In ASTM E252, the thickness is calculated using the following relationship,

Where,

T = thickness of the foil, sheet, or film, inch (or cm),

M = mass of the specimen, g,

A = area of the specimen, inch² (or cm²), and

D = density of the foil, sheet, or film, g/inch³ (or mg/m³).

Conclusion:

ASTM E252 standard test covers the procedure to estimate the thickness of metallic foils and thin sheets.