Reduction of surface oxide layers on water-atomized iron and steel powder in hydrogen: Effect of alloying elements and initial powder state
Artikel i vetenskaplig tidskrift, 2020

The reduction of surface oxide layers covering commercial water-atomized iron and steel powder grades have been investigated using model thermogravimetric reduction cycles in hydrogen. The influences of powder composition and initial condition on the oxide reduction were studied for three powder grades and compared to Fe2O3. Isothermal and dynamic measurements were conducted to assess the reduction progress and kinetic analyses were then used to calculate the apparent activation energies of reduction. Chromium-alloyed powder showed significantly lower activation energies compared to iron powder and Fe2O3, likely originating from the presence of Cr oxide in the oxide layer. The reduction was also found to be strongly affected by the initial state of the oxide layer which reflects the powder production. Surface analysis by X-ray photoelectron spectroscopy (XPS) showed a progressive increase in Cr with gradual reduction of the oxide layer, indicating its presence and possible involvement in the oxide reduction.

thermogravimetric analysis

oxide reduction

water-atomized iron powder

reduction kinetics

water-atomized steel powder

Författare

Johan Wendel

Chalmers, Industri- och materialvetenskap, Material och tillverkning

Swathi Kiranmayee Manchili

Chalmers, Industri- och materialvetenskap, Material och tillverkning

Eduard Hryha

Chalmers, Industri- och materialvetenskap, Material och tillverkning

Lars Nyborg

Chalmers, Industri- och materialvetenskap, Material och tillverkning

Thermochimica Acta

0040-6031 (ISSN)

Vol. 692 1-10

Nanoteknikstödd tillverkning av högpresterande sinterstål

Stiftelsen för Strategisk forskning (SSF), 2016-01-01 -- 2020-12-31.

Styrkeområden

Produktion

Ämneskategorier

Metallurgi och metalliska material

DOI

10.1016/j.tca.2020.178731

Mer information

Senast uppdaterat

2020-09-04