Internal oxidation processing: New alloys and new simulation techniques
2004 (English)Doctoral thesis, comprehensive summary (Other scientific)
Nitriding and oxidising treatments of alloys for toolingpurposes have been investigated both experimentally andtheoretically. Specimens prepared by a combination of differentprocessing steps are investigated by light-optical, scanningand transmission electron microscopy and hardness measurments.The bounds of carbon and nitrogen concentration profiles duringnitriding are obtained from simulations using the DICTRA code.As a result, a new processing route to produce oxide-dispersediron-base alloys with large volume fraction of carbides issuggested.
On the theoretical side the methods based on the random walktechnique have been investigated and developed further. The newmethods have been applied to study a vide range of phenomenae.g. internal oxidation, diffusion in inhomogeneous media,phase transformations and formation of porosity due to theKirkendall effect in welded joints. Probability distributionsare introduced to replace random number generators in order toincrease computational efficiency. A general method to simulatediffusional phase transformations in multicomponent systems isdeveloped and applied to ternary alloys.
Place, publisher, year, edition, pages
Stockholm: KTH , 2004. , x, 33 p.
Internal oxidation, nitriding, diffusion, simulation, random walk
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-3715ISBN: 91-7283-706-3OAI: oai:DiVA.org:kth-3715DiVA: diva2:9555
2004-03-19, 00:00 (English)
QC 201005062004-03-082004-03-082010-05-06Bibliographically approved
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