Oxide Distribution in Prealloyed Water Atomized Steel Powder
Paper in proceedings, 2010

A method for evaluation of the oxygen distribution in both the surface and the interior of water-atomized powder was developed. Pre-alloyed powder with 3wt.% Cr and 0.5 wt.% Mo was chosen as the model material. Surface chemical composition with regard to composition, morphology, size and distribution of surface oxides was studied by means of surface analytical techniques (XPS, Auger, SEM and EDX). The analysis revealed that the powder particles are covered by a homogeneous (~6 nm thick) Fe-oxide layer and some spherical particulate features with size up to 200 nm that were complex Fe-Cr-Mn-Si-oxides, surface coverage of which is <10%. About 45% of total oxygen content is in the form of easily-reducible iron oxide layer. Remaining oxygen is linked to the surface stable oxides and internal complex oxides. Study of the internal oxides using EDX Smart-Maps tool reveals presence of inclusions below 1μm in size and rich in Cr and Mn.

surface oxides

surface coverage

XPS analysis

alloyed sintered steels

water atomized powder

internal oxides

HR SEM+EDX analysis

Author

Dimitris Chasoglou

Chalmers, Materials and Manufacturing Technology, Surface and Microstructure Engineering

Eduard Hryha

Chalmers, Materials and Manufacturing Technology, Surface and Microstructure Engineering

Lars Nyborg

Chalmers, Materials and Manufacturing Technology, Surface and Microstructure Engineering

World Powder Metallurgy Congress and Exhibition, World PM 2010; Florence; Italy; 10 October 2010 through 14 October 2010

Vol. 1 61-69

Subject Categories

Materials Engineering

Manufacturing, Surface and Joining Technology

ISBN

978-189907219-4

More information

Created

10/7/2017