Influence of scandium addition on the high-temperature grain size stabilization of oxide-dispersion-strengthened (ODS) ferritic alloy

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:636

Article

Li, Lulu¹  Xu, Weizong¹  Saber, Mostafa¹  Zhu, Yuntian¹  Koch, Carl C.¹  Scattergood, Ronald O.¹ 

[1] N Carolina State Univ, Dept Mat Sci & Engn, Raleigh, NC 27695 USA

关键词: Mechanical alloying;    Oxide-dispersion-strengthened alloy;    Thermal stability;    Sc stabilization;   

DOI  :  10.1016/j.msea.2015.03.117

来源: Elsevier

【 摘 要 】

The influence of 1-4 at% Sc addition on the thermal stability of mechanically alloyed ODS ferritic alloy was studied in this work. Sc addition was found to significantly stabilize grain size and microhardness at high temperatures. Grain sizes of samples with 1 and 4 at% Sc was found maintained in the nanoscale range at temperatures up to 1000 degrees C with hardness maintained at 5.6 and 6.7 GPa, respectively. The detailed microstructure was also investigated from EDS elemental mapping, where nanofeatures [ScTiO] were observed, while nanosized [YTiO] particles were rarely seen. This is probably due to the concentration difference between Sc and Y, leading to the formation of [ScTiO] favoring that of [YTiO]. Precipitation was considered as the major source for the observed high temperature stabilization. In addition, 14YT-Sc alloys without large second phases such as Ti-oxide can exhibit better performance compared to conventional ODS materials. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

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