Microstructure and Direct Measured Micro-Strain by TEM of Hot Iso-Static Pressed Alumina-Titanium Carbide (Al₂O₃-TiC) Composite

Abstract:

Alumina-titanium carbide composite (Al₂O₃-TiC) is one of advance ceramic matrix composites (CMC) that have been used in machining tool and tribology application because of its excellent mechanical properties. Powder processing is often a chosen method to produce this family of material, i.e. hot pressed (HP), hot iso-static pressed (HIP), and pressure-less sintering (PS). These manufacturing techniques convert sub-micron powder into dense bulk component. Al₂O₃-TiC composite has been prepared by HIP process, containing 65%vol Al₂O₃ and 35%vol TiC. The powders were pressured and sintered at temperature between 1250˚C - 1650˚C. Thermal residual stress from Al₂O₃-TiC manufacturing process is conventionally unavoidable. The aim of this study is to investigate the microstructure of HIPped Al₂O₃-TiC composite and its residual micro-strain using transmission electron microscopy (TEM) with selected area electron diffraction pattern (SADP) analysis. The Al₂O₃-TiC composite was prepared by high-precision machining/grinding processes then focus ion beam milling process was used to section the TEM lamella. Microstructures, grain size and phases were determined by TEM and X-ray diffractometry (XRD). Micro-strains of {200}TiC, {111}TiC , {220}TiC and {012}Al₂O₃ were investigated by SADP (Selected Area Diffraction Pattern). Our result revealed there is approximately 0.01 compressive strains distributed in Al₂O₃-TiC composite.

• Periodical: Advanced Materials Research (Volume 983)
• Pages: 156-160
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.983.156
• Online since: June 2014
• Authors: Sineenart Thumsoontorn, Surasak Kuimalee, Budsabong Kuntalue, Suphakit Pintasiri, Boonrat Lohwongwatana*
• Keywords: Al₂O₃-TiC Composite, AlTiC, FIB-TEM Sample Preparation, HIP, Micro-Strain

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