Helbig & Lang - The surface finishing specialist

Machu Test

The Machu test is a short-term corrosion test for aluminium and steel and can be realised in our test laboratory. In contrast to the (acetic acid) salt spray test, the machu test can be used to test coating results after a short test period. So the Machu test delivers fast results. At the same time, the results of the Machu test show a high correlation with the results of the salt spray test. Therefore, the Machu test is often used as a quick test before a salt spray test is launched.

In the Machu test, a cross section is cut down to the metal of the test panel. Then the sample plate is stored in an acid test solvent at a test temperature of 37°C for a period of 48 hours. The test solvent consists of sodium chloride, glacial acetic acid and hydrogen peroxide. The test result fulfills the test requirements, if the underlay at the scribe is not larger than 0.5 mm.