Phase formation capability and compositional design of β-phase multiple rare-earth principal component disilicates.

A key strategy to design environmental barrier coatings focuses on doping multiple rare-earth principal components into β-type rare-earth disilicates (RESiO) to achieve versatile property optimization. However, controlling the phase formation capability of (nRE)SiO remains a crucial challenge, due to the complex polymorphic phase competitions and evolutions led by different RE combination. Herein, by fabricating twenty-one model (RERERERE)SiO compounds, we find that their formation capability can be evaluated by the ability to accommodate configurational randomness of multiple RE cations in β-type lattice while preventing the β-to-γ polymorphic transformation.

Unique chemical activity in porous YbBC ceramics with high porosity and high compressive strength.

High purity layered YbBC powder is synthesized by a boro/carbothermic reduction method using YbBO, BC and graphite powders as raw materials. Its X-ray diffraction data are presented, and the space group P4/mbm (No. 127) is confirmed.

Tunable properties of (HoY)SiO as damage self-monitoring environmental/thermal barrier coating candidates.

RESiO with low thermal conductivity, compatible thermal expansion coefficients and excellent high-temperature reliability in harsh environments are excellent candidates as advanced environmental/thermal barrier coating materials for high-efficiency gas turbine engines. A series of rare earth silicates (HoY)SiO are designed and their properties are comprehensively investigated in this paper. Through doping Ho into YSiO, the thermal conductivity of YSiO is significantly decreased and the thermal expansion coefficient is also optimized closer to Si-based ceramics.

Comparative transcriptome analyses of three medicinal Forsythia species and prediction of candidate genes involved in secondary metabolisms.

The three Forsythia species, F. suspensa, F. viridissima and F.