Metal Dusting

Exposure at high temperature in gas mixtures can lead to different degradation processes such as sulphidization (in mixtures containing sulfur such a as SO2 or SO3), chlorination (ClH, Cl2, etc) nitriding (NOx) and carburizing (CH4, CO, CO2).

Within this possible process attention must be drawn the process called "metal Dusting" that occurs in reducing atmospheres with a high hydrogen content CH4 and CO2 which produces atmospheres with carbon activity higher than 1.

This leads to the precipitation of carbon (graphite) on the surface of the material in places where the protective Cr2O3 scale is discontinuous and it penetrates the surface of the material, forming unstable carbides that spall easily.

In this research activity the materials investigated are Al2O3 and CR2O3 forming materials and the effect of preoxidation and surface finish is studied.

In addition, different protective for this conditions coatings are analyzed, particularly Si, and their deposition with different techniques is investigated.

Metal Dusting

Metal Dusting

Photos: Metal Dusting

Publications Metal Dusting

- Confidential reports for companies.