ISSN:
1662-9752
Quelle:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Thema:
Maschinenbau
Notizen:
A novel technique has been developed to prepare micro-/nano-crystal aluminized ODScoatings on stainless steel and nickel-base superalloy. In this technique, the pack aluminizing iscombined with the repeated ball impact. Pure Al powder is mixed with 1wt% Y2O3 powder by ballmilling. The ultrafine Y2O3 powder is well dispersed in Al particles. The modified Al particles arewelded to the surface of metals by ball impact, causing the refinement of coarse grains andacceleration of atomic diffusion. Micro-/nano-crystal alloy layer with Y2O3 grows outward at amuch low temperature (below 600°C) and in short treatment duration, compared with conventionalpack aluminizing. The effects of processing temperature and duration on formation of the coatingshave been analyzed. The microstructure of the coatings is studied using the methods of SEM, AMF,EDS, XRF and XRD. The results indicate that the aluminized ODS coatings appear to be dense,homogeneous, micro-/nano-crystal structure, and consist mainly of Al-rich phases, such as Fe2Al5,FeAl3 NiAl3 and7 CrAl5. High temperature oxidation tests show that the coatings enhance theoxidation resistance
Materialart:
Digitale Medien
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/13/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.522-523.323.pdf
