Alternative Fabrication Routes toward Oxide-Dispersion-Strengthened Steels and Model Alloys
- PDF / 2,214,394 Bytes
- 12 Pages / 593.972 x 792 pts Page_size
- 85 Downloads / 177 Views
HE development of oxide-dispersion-strengthened (ODS) steels reaches back to the 1960s[1] (also References 2 and 3 and references therein) and has been continuing since.[4–6] ODS steels have been shown to offer improved
FRANK BERGNER, Senior Scientist, and ISABELL HILGER, Graduate Student at TU Dresden, are with the Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum DresdenRossendorf, P.O. Box 510119, 01314 Dresden, Germany. Contact e-mail: [email protected] JOUKO VIRTA, Senior Scientist, is with VTT Technical Research Centre of Finland Ltd., P.O. Box 1000, 02044 VTT, Finland. JUHA LAGERBOM, Senior Scientist, is with VTT Technical Research Centre of Finland Ltd., P.O. Box 1300, 33101 Tampere, Finland. GUNTER GERBETH, Head, is with the Institute of Fluid Dynamics, Helmholtz-Zentrum Dresden-Rossendorf, P.O. Box 510119, 01314 Dresden, Germany. PATRICK S. GRANT, Professor and Head, and SARAH CONNOLLY and ZULIANG HONG, Research Students, are with the Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK. THOMAS WEISSGA¨RBER, Head, is with the Department of Sintered and Composite Materials, Fraunhofer Institute IFAM, Branch Lab Powder Metallurgy and Composite Materials, Winterbergstraße 28, 01277 Dresden, Germany. Manuscript submitted February 2, 2016 METALLURGICAL AND MATERIALS TRANSACTIONS A
creep strength over their nonstrengthened equivalents, extending the potential application window of conventional high-Cr steels from less than 873 K (600 C)[2,7] toward 1073 K (800 C),[8] while maintaining other favorable properties of high-Cr steels, in particular in civil nuclear power environments. It is interesting to note that while powder metallurgy (PM) fabrication routes, including milling and consolidation of steel/oxide powder blends or controlled oxidation of Y-alloyed steel powders, were considered from the very beginning,[1,2,9] the notion of mechanical alloying (MA) did not make a significant appearance in the literature until 1970.[10] After a period of research and development, commercial ODS products became available in the 1990s, and two lines of scientific effort received special interest. First, composition and processing parameters were varied to obtain optimum microstructures or optimum mechanical properties. For instance, in a key finding, it was shown that the addition of approximately 0.4 wt pct Ti to a master alloy gave rise to a reduction in the oxide-particle size from approximately 20 nm to about 2 nm[5] and an improvement in creep resistance. Consolidation techniques for MA powders include hot-isostatic pressing (HIP), hot extrusion (HE), and, more recently, pulsed-current-assisted sintering
also known as spark plasma sintering (SPS) or field-assisted sintering technique (FAST). The role of postprocessing of consolidated products including thermomechanical treatment (TMT) has also been investigated extensively. Second, significant effort was expended by the desire to simplify the overall process, to make it less expensive, more reproducible, and to allow scalin
Data Loading...
