Sample preparation and microstructural characterization of the gamma titanium aluminide Ti-48Al-2W-0.5Si
Journal article, 1997

Preparing samples that faithfully reveal all microstructural features in γ-TiAl-base alloys for both optical and scanning electron microscope studies is fraught with difficulties. This study demonstrates that satisfactory results can be obtained through mechanical grinding, polishing, and proper etching. A preparation recipe is presented. Nine lots of investmentcast γ-TiAl material with the nominal composition of Ti-48Al-2W-0.5Si have been characterized through optical and scanning electron microscope examinations. The study shows that a small depletion in Al content has a large effect on the microstructure. The duplex microstructure with a lamellar Full-size image (<1 K) colony size of about 500μm and a large percentage of singlephase γ grains as large as 200μm is altered to a coarse, nearly lamellar microstructure with a colony size as large as 5000μm and a small percentage of small single-phase γ grains in the colony boundaries.


Viktor Recina

Department of Engineering Metals

Johan Ahlström

Department of Engineering Metals

Birger Karlsson

Department of Engineering Metals

Materials Characterization

1044-5803 (ISSN)

Vol. 38 4-5 287-300

Areas of Advance


Materials Science


Basic sciences

Subject Categories

Other Materials Engineering

Metallurgy and Metallic Materials



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