Refractory intermetallic compound Nb3Al is expected as a candidate for structural materials operated at much higher temperatures compared to conventional Ni superalloys. This paper presents research work on laser deposition of a powder blend of Nb, Ti, Al pure elements to form Nb 3Al intermetallic compound. The research focuses on an alloy composition of Nb-12Ti-22Al (at.%). The fine δ-Nb 3Al/β-Nbss intermetallic compound with a composition close to the atom ratios of the elemental powder blend was obtained by laser deposition in an argon atmosphere chamber. The microstructure characterization and phase identification were analyzed by XRD, SEM and TEM. The fine δ/β compound has an average microhardness up to HV0.21022. Although Nb3Al has a negative formation enthalpy, high laser energy density is needed for Nb3Al formation by peritectic reaction. There is a critical crack-free height in laser deposition of Nb3Al under appropriate processing parameters. Beyond the height, the sample cracks due to residual tensile stress induced during laser deposition.
|Number of pages||6|
|Publication status||Published - 2005|
|Event||24th International Congress on Applications of Lasers and Electro-Optics, ICALEO 2005 - Miami, FL, United States|
Duration: 2005 Oct 31 → 2005 Nov 3
|Other||24th International Congress on Applications of Lasers and Electro-Optics, ICALEO 2005|
|Period||05/10/31 → 05/11/3|
ASJC Scopus subject areas