Breviary Technical Ceramics



 Corrosion in the Melt Test conditions

Corrosion tests must always be properly related to the real conditions of the application. The relevant stress criteria, and the way in which the material can be expected to behave as it interacts with the corroding medium, must be estimated beforehand.

Points that need consideration include:

  • thermal stresses,
  • chemical aspects,
  • the type of material to be examined and
  • mechanical stress. Bestimmung der Korrosionshöhe

Test procedures for corrosion in the melt are, in contrast to liquid phase corrosion, covered by national and international standards. The most important of these standards are:

  • measurements of the wetting angle using an HT reflected light microscope,
  • the crucible slagging process (DIN 51069-2),
  • the scattering and tapping process (ASTM C 768) and
  • the dip process (finger test) (ASTM C 874).

In summary: The corrosion of refractory materials in liquid slags and metallic melts is a complex process whose details are difficult to understand. Standardised test procedures are therefore only relevant if they reflect the conditions that will apply in practice.