Synthesis of Fe-Al-Ti Based Intermetallics with the Use of Laser Engineered Net Shaping LENSReport as inadecuate




Synthesis of Fe-Al-Ti Based Intermetallics with the Use of Laser Engineered Net Shaping LENS - Download this document for free, or read online. Document in PDF available to download.

Department of Advanced Materials and Technologies, Military University of Technology, 2 Kaliskiego Str., 00-908 Warsaw, Poland





*

Author to whom correspondence should be addressed.



Academic Editor: Marco Salerno

Abstract The Laser Engineered Net Shaping LENS technique was combined with direct synthesis to fabricate L21-ordered Fe-Al-Ti based intermetallic alloys. It was found that ternary Fe-Al-Ti alloys can be synthesized using the LENS technique from a feedstock composed of a pre-alloyed Fe-Al powder and elemental Ti powder. The obtained average compositions of the ternary alloys after the laser deposition and subsequent annealing were quite close to the nominal compositions, but the distributions of the elements in the annealed samples recorded over a large area were inhomogeneous. No traces of pure Ti were observed in the deposited alloys. Macroscopic cracking and porosity were observed in all investigated alloys. The amount of porosity in the samples was less than 1.2 vol. %. It seems that the porosity originates from the porous pre-alloyed Fe-Al powders. Single-phase L21, two-phase L21-C14 and multiphase L21-A2-C14 Fe-Al-Ti intermetallic alloys were obtained from the direct laser synthesis and annealing process. The most prominent feature of the ternary Fe-Al-Ti intermetallics synthesized by the LENS method is their fine-grained structure. The grain size is in the range of 3–5 μm, indicating grain refinement effect through the highly rapid cooling of the LENS process. The Fe-Al-Ti alloys synthesized by LENS and annealed at 1000 °C in the single-phase B2 region were prone to an essential grain growth. In contrast, the alloys annealed at 1000 °C in the two-phase L21-C14 region exhibited almost constant grain size values after the high-temperature annealing. View Full-Text

Keywords: iron aluminides; LENS; laser cladding; rapid solidification alloying; microstructure; synthesis iron aluminides; LENS; laser cladding; rapid solidification alloying; microstructure; synthesis





Author: Monika Kwiatkowska, Dariusz Zasada, Jerzy Bystrzycki and Marek Polański *

Source: http://mdpi.com/



DOWNLOAD PDF




Related documents