Analysis of Iron Oxide Reduction Kinetics in the Nanometric Scale Using Hydrogen
Journal article, 2020

Iron nanopowder could be used as a sintering aid to water-atomised steel powder to improve the sintered density of metallurgical (PM) compacts. For the sintering process to be efficient, the inevitable surface oxide on the nanopowder must be reduced at least in part to facilitate its sintering aid effect. While appreciable research has been conducted in the domain of oxide reduction of the normal ferrous powder, the same cannot be said about the nanometric counterpart. The reaction kinetics for the reduction of surface oxide of iron nanopowder in hydrogen was therefore investigated using nonisothermal thermogravimetric (TG) measurements. The activation energy values were determined from the TG data using both isoconversional Kissinger–Akahira–Sunose (KAS) method and the Kissinger approach. The values obtained were well within the range of reported data. The reaction kinetics of Fe 2 O 3 as a reference material was also depicted and the reduction of this oxide proceeds in two sequential stages. The first stage corresponds to the reduction of Fe 2 O 3 to Fe 3 O 4, while the second stage corresponds to a complete reduction of oxide to metallic Fe. The activation energy variation over the reduction process was observed and a model was proposed to understand the reduction of surface iron oxide of iron nanopowder

Nanopowder

Activation energy

Thermogravimetry

Conversion factor

Author

Swathi Kiranmayee Manchili

Chalmers, Industrial and Materials Science, Materials and manufacture

Johan Wendel

Chalmers, Industrial and Materials Science, Materials and manufacture

Eduard Hryha

Chalmers, Industrial and Materials Science, Materials and manufacture

Lars Nyborg

Chalmers, Industrial and Materials Science, Materials and manufacture

Nanomaterials

20794991 (eISSN)

Vol. 10 7 1-17 1276

Subject Categories

Inorganic Chemistry

Materials Chemistry

Metallurgy and Metallic Materials

DOI

10.3390/nano10071276

More information

Latest update

8/19/2020