Strain heterogeneity and the production of coarse grains in mechanically alloyed iron-based PM2000 alloy

C. Capdevila, U. Miller, H. Jelenak and H. K. D. H. Bhadeshia


Mechanically alloyed iron-based ODS alloys have the potential for application in heat exchangers for biomass processing, with gas operating temperatures and pressures of approximately 1100°C and 15-30 bar. The yttria dispersion in such alloys improves the high-temperature creep and stress rupture life. The elevated temperature strength is enhanced by the development of a coarse-grained microstructure during recrystallisation. Factors controlling the evolution of this desirable microstructure are explored in this work, focusing specifically on PM2000, which is a yttria dispersion strengthened, mechanically alloyed material. The microstructure following mechanical alloying and consolidation is fine and uniform, making it difficult to nucleate recrystallisation. Therefore, the introduction of a strain heterogeneity in the microstructure is found to promote the nucleation of recrystallisation. In contrast, uniform deformation reduces the chances of nucleation and hence leads to the development of a coarser microstrutructure.

Materials Science and Engineering A, Vol. A316, 2001, 161-165.

Download PDF File This file is reprinted from Materials Science and Engineering with permission from Elsevier Science. Single copies of the article can be downloaded and printed for the reader's personal research and study.

More resources on this topic

Envelope Coefficients Filling welds Hot Delta
Satoh Fields Piping European welds Poles
Mixed Creep Extraordinary ductility Problems Low temperatures

PT Group Home Materials Algorithms