Structural stability of sintered Fe40Al composites dopeedwith Al2O3 nanoceramics
Tomasz Durejko, Adrian Strąk, Stanisław Lipiński
Quarterly No. 3, 2011 pages 225-229
DOI:
keywords: powders metallurgy, structural stability, ODS sinters
abstract Temperature and time of heat treatment influence on the structural stability of Fe40Al intermetallic alloy with and without addition of alumina ceramics was investigated. Low energy milling in a ball mill was applied for material manufacturing. The batches were formed by cold-consolidation at 300 MPa pressure. Initial sintering was carried out at 1050˚C under 40 MPa of charge for 15 minutes in vacuum. The last step of Fe40Al sinters (with and without alumina nanoceramics addition, manufacturing was essential sintering). The process was carried out in tube oven with constant ambient gas flow (argon atmosphere) at 1200˚C for 1 hour. On classically prepared metallographic cross-section of samples with various additions of alumina nanoceramics, analysis of structure was carried out after initial and essential sintering. For all the technological options stereological investigations of grain size descriptions were done after full cycle of heat treatment. Material was cyclically heated at 800 and 1000˚C in air atmosphere for 150 h. Obtained results reveals that long heating of the Fe40Al intermetallic alloy based sinters leads to gradual grain growth of the matrix. Changes in grain size showed that doping with alumina nanoceramics in Fe40Al inhibits grain growth.