Surface composition of the steel powders pre-alloyed with manganese
Artikel i vetenskaplig tidskrift, 2010

The determination of the surface oxide layer composition is vital to facilitate the adjustment of the sintering conditions for sufficient removal of the surface oxides for providing strong metal bonding between the metal particles during sintering. To systematically investigate the composition, morphology and thickness of the surface oxide the influence of manganese content from 0.3 to 1.8 wt.% on the surface products composition in the case of water atomized steel powder was evaluated. Analysis of the powder surfaces by X-ray photoelectron spectroscopy and high-resolution scanning electron microscopy in combination with X-ray microanalysis showed that powder particles in all cases are covered by heterogeneous oxide layer, composed of particulate features of thermodynamically stable oxides (Cr-Mn-Si) and homogeneous iron surface oxide layer in between. For increasing alloying content the fraction of stable oxide cations in the surface layer increases linearly, whereas the thickness of the iron oxide layer decreases. Moreover, from the investigation of the sintering and degassing behavior by thermal analysis coupled with mass-spectrometry (TG/DTA + MS), three different stages of carbothermal reduction process were observed and their correlation with surface oxides composition was established during sintering in argon.

Thermal analysis

Surface oxides

mechanical-properties

o system

sintered steels

PM steels

Mass-spectroscopy

sofc interconnect

oxidation

stainless-steel

XPS analysis

microstructure

mn

cr

Carbothermal reduction

Författare

Eduard Hryha

Chalmers, Material- och tillverkningsteknik, Yt- och mikrostrukturteknik

Christian Gierl

Technische Universität Wien

Lars Nyborg

Chalmers, Material- och tillverkningsteknik, Yt- och mikrostrukturteknik

Herbert Danninger

Technische Universität Wien

Eva Dudrova

Slovenská akadémia Vied

Applied Surface Science

0169-4332 (ISSN)

Vol. 256 12 3946-3961

Ämneskategorier

Bearbetnings-, yt- och fogningsteknik

DOI

10.1016/j.apsusc.2010.01.055

Mer information

Senast uppdaterat

2019-06-10