Alumina scale formation on a powder metallurgical FeCrAl alloy (Kanthal APMT) at 900-1100°C in dry O2 and in O2 + H2O
Artikel i vetenskaplig tidskrift, 2010

A Rapidly Solidified Powder (RSP) metallurgical FeCrAl alloy, Kanthal APMT, was exposed in dry and humid O-2 for 72 h at 900-1,100 A degrees C. The formed oxide scales were characterized using gravimetry in combination with advanced analysis techniques (SEM, EDX, TEM, XRD, AES and SIMS). The oxide scales were at all exposures composed of two-layered alpha-Al2O3 scales exhibiting a top layer of equiaxed grains and a bottom layer containing elongated grains. A Cr-rich zone, originating in the native oxide present before exposure, separated these two layers. The top alpha-Al2O3 layer is suggested to have formed by transformation of outwardly grown metastable alumina, while the inward-grown bottom alpha-Al2O3 layer had incorporated small Zr-, Hf- and Ti-rich oxide particles present in the alloy matrix. The scale also contained larger Y-rich oxide particles. Furthermore, in the temperature range studied, the presence of water vapour accelerated alloy oxidation somewhat and affected scale morphology.

Oxidation

FeCrAl

Alumina

Water vapour

Författare

Josefin Engkvist

Chalmers, Kemi- och bioteknik, Oorganisk miljökemi

Sead Canovic

Chalmers, Teknisk fysik, Mikroskopi och mikroanalys

Kristina M Hellström

Chalmers, Kemi- och bioteknik, Oorganisk miljökemi

Anders Järdnäs

Chalmers, Kemi- och bioteknik, Oorganisk miljökemi

Jan-Erik Svensson

Chalmers, Kemi- och bioteknik, Oorganisk miljökemi

Lars-Gunnar Johansson

Chalmers, Kemi- och bioteknik, Oorganisk miljökemi

M. Olsson

Hogskolan Dalarna

Mats Halvarsson

Chalmers, Teknisk fysik, Mikroskopi och mikroanalys

Oxidation of Metals

0030-770X (ISSN) 1573-4889 (eISSN)

Vol. 73 1 233-

Ämneskategorier

Oorganisk kemi

Övrig annan teknik

DOI

10.1007/s11085-009-9177-7

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Senast uppdaterat

2018-11-05