Article ID Journal Published Year Pages File Type
1499947 Scripta Materialia 2011 4 Pages PDF
Abstract

The microstructure of oxide scales formed on Ti2AlC surface after oxidation at 1200 °C is investigated. The results reveal an inhomogeneous morphology of the oxide scales, i.e. islands of coarse rutile grains pile up on fine-grained Al2O3 layer. Local cross-sectional observations show that the rutile islands grow on top of cavities in the parent material. A model is proposed to describe the resulting microstructure after oxidation. These results are relevant in optimizing the self-healing conditions of Ti2AlC at high temperature.

► Inhomogeneous morphology of oxides formed on Ti2AlC surface during high temperature oxidation. ► Initial surface curvature attribute to this non-uniform oxidation behavior. ► A columnar layer of Al2O3 was observed between the matrix and equiaxed grain layer on flat surface. ► The Al-ion consumption in cavity is larger than on flat surface during oxidation. ► Porosity and cavity provide paths for outward diffusion of Ti-ion during oxidation.

Related Topics
Physical Sciences and Engineering Materials Science Ceramics and Composites
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