Patent ID: 7115327
Filing Date: 2006-10-03
Classification: C04B,C23C,F05B,F05C,Y10T

Abstract:
1. An article comprising: a) a substrate formed of a silicon-comprising material; b) an environmental barrier layer overlying the substrate; and c) a transition layer overlying the environmental barrier layer, the transition layer comprising hafnia stabilized with an oxide of a metal selected from the group consisting of magnesium, calcium, scandium, yttrium, and lanthanide metals; and a low CTE oxide selected from the group consisting of niobia and tantala; and mixtures thereof; and d) a top coat overlying the transition layer, the top coat comprising zirconia or hafnia stabilized with an oxide of a metal selected from the group consisting of magnesium, calcium, scandium, yttrium, and lanthanide metals, and mixtures thereof.