Analysis of surface texture of FeAl+Al2O3 oxide dispersion-strengthened sinters
Tomasz Durejko, Zbigniew Zarański, Stanisław Sulej Wojskowa Akademia Techniczna, Wydział Nowych Technologii i Chemii, Katedra Zaawansowanych Materiałów i Technologii ul. Kaliskiego 2, 00-908 Warszawa, Poland
Quarterly No. 1, 2007 pages 41-45
DOI:
keywords: oxide dispersion-strengthened (ODS) sinters, surface texture (ST), load capacity curve, abrasive wear resistance
abstract The oxide dispersion-strengthened (ODS) sinters were obtained via two-stage sintering of technically pure iron and alu-minum powders with a 1% volumetric addition of nanometric alpha-Al2O3. In the first stage of a processing, a powder charge was compacted/sintered in two technological variants differing in compacting pressure (static or cyclically variable one). Structurally inhomogeneous powder compacts were then loosely sintered in argon envelope. The obtained sinters with com-posite structures were characterized through their density and surface texture (ST) immediately after technological process. On the base of measured roughness profiles a load capacity curve and quantitative parameters determining abrasive wear resistance of investigated sinters were found. Additionally, a 3D spatial roughness profile was registered for each sample. Experimental verification of the results obtained from load capacity curves was carried out in abrasive wear resistance tests using pin-on-disc method. A linear wear degree and a mass decrement were determined for each sinter. It was found that sinter density depends on a load type applied during initial sintering. Densities in the order of 91 and 94% of the theoretical value were obtained for statically sintered compact and for that under cyclically variable load, respectively. Tests of com-pacts’ surface texture showed lower roughness and higher abrasive wear resistance for samples after initial sintering with 40 Hz load. The obtained results were confirmed by a wear test in which more than twice as low drop of mass decrement and linear wear were measured for sintered materials during uniaxial compaction in elevated temperature with mechanical force of the cyclically variable load type.