Dissolution of carbon in Cr-prealloyed PM steels: effect of carbon source
Artikel i vetenskaplig tidskrift, 2015

Modern water-atomised steel powder grades are characterised by the presence of two types of surface oxides: a thin iron oxide layer, covering more than 90% of the powder surface, and more thermodynamically stable particulate oxides. The development of inter-particle necks and carbon dissolution in the iron matrix both require efficient removal of the iron oxide layer. Hence, carbon reactivity strongly affects the surface oxide reduction that determines inter-particle neck development and carbon dissolution, and so microstructure development. An analysis is presented of the effect of three carbon sources – synthetic graphite, natural graphite and carbon black – on microstructure and inter-particle neck development in Cralloyed PM steels. Metallographic and fractographic studies indicate that the most significant property of the carbon sources affecting reactivity is the carbon powder size. Carbon black shows the highest reactivity at elevated temperatures but is fully inert at temperatures below 900uC.

graphite dissolution

powder metallurgy

chromium alloyed PM steels

graphite

carbothermal reduction

Författare

Eduard Hryha

Chalmers, Material- och tillverkningsteknik, Yt- och mikrostrukturteknik

Lars Nyborg

Chalmers, Material- och tillverkningsteknik, Yt- och mikrostrukturteknik

Luigi Alzati

TIMCAL Ltd.

Powder Metallurgy

0032-5899 (ISSN) 1743-2901 (eISSN)

Vol. 58 1 7-11

Drivkrafter

Hållbar utveckling

Styrkeområden

Produktion

Materialvetenskap

Ämneskategorier

Materialkemi

Metallurgi och metalliska material

DOI

10.1179/0032589914Z.000000000191

Mer information

Skapat

2017-10-07