Hot corrosion of metals and alloys — State-of-the-art test equipment

Increasing the energy efficiency of turbomachinery, furnaces and boilers is a major challenge for manufacturers in the aerospace, transport and energy sectors. To achieve this objective, the components of these installations exposed to combustion gases are subjected to increasingly high mechanical stresses and temperatures, resulting in a need for more refractory materials. Indeed, these high-temperature stresses can lead to material degradation through fatigue and creep, and/or oxidation and hot corrosion. The resistance of these alloys to this environment has a major impact on their mechanical properties and, consequently, on the service life of parts.

The choice of refractory materials is an essential step in guaranteeing the longevity of mechanical systems, but the key is to be able to test them under conditions close to actual operating conditions. There are now numerous test facilities for testing alloys under high-temperature air oxidation conditions, but very few for high-temperature corrosion testing under "complex" atmospheres (corrosion by a mixture of gases, corrosive deposits or molten salts). This article reviews the various hot corrosion test facilities available in France and around the world. It presents the strengths and limitations of the various test benches.

In 2021, it should be noted that, although hot corrosion tests are carried out throughout the world, no standard governs the experimental methodology or operation of these test benches, even though the term is defined in standard NF EN ISO 8044 .

This article provides additional information to the articles :

• [COR 378] High-temperature gas corrosion of refractory metals and alloys;

• [M 4 220] Dry corrosion of metals – Study methods ;

• [M 4 221]...