Related Experiment Video
Updated: May 6, 2026
07:37
TiO2-coated Hollow Glass Microspheres with Superhydrophobic and High IR-reflective Properties Synthesized by a Soft-chemistry Method
Published on: April 26, 2017
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Functionally Graded Oxide Scale on (Hf,Zr,Ti)B2 Coating with Exceptional Ablation Resistance Induced by Unique Ti
Junshuai Lv1, Wei Li1, Yanqin Fu2
1Shaanxi Key Laboratory of Fiber Reinforced Light-Weight Composites, State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an, 710072, China.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|January 15, 2025
Summary
Titanium (Ti) addition significantly enhances ultra-high temperature ceramics (UHTCs) for extreme heat applications. Ti improves ablation resistance by refining grain structure and creating a protective oxide scale with superior crack inhibition.
Area of Science:
- Materials Science
- Ceramic Engineering
- High-Temperature Materials
Background:
- Ultra-high temperature ceramics (UHTCs) are crucial for applications exceeding 2000 °C.
- Titanium (Ti)-containing UHTCs show enhanced ablation resistance, but the mechanism is unclear.
- Understanding Ti's role is vital for developing advanced thermal protection systems.
Purpose of the Study:
- To investigate the effect of Ti content on the ablation performance of (Hf,Zr,Ti)B2 coatings.
- To elucidate the mechanism by which Ti improves ablation resistance.
- To optimize UHTCs for extreme temperature environments.
Main Methods:
- Fabrication of (Hf,Zr,Ti)B2 coatings using supersonic atmospheric plasma spraying.
- Ablation testing under an oxyacetylene flame at approximately 2200 °C.
- Microstructural analysis of the resulting oxide scale.
Main Results:
- The (Hf0.45Zr0.45Ti0.10)B2 coating exhibited superior ablation resistance and cycling reliability.
- A functionally graded oxide scale formed, with a dense outer layer and a fine granular inner layer.
- Ti dissolution refined grains, released stress, and formed a metastable cubic oxide scale, inhibiting crack propagation.
Conclusions:
- Ti incorporation in UHTCs creates a robust oxide scale with excellent oxygen barrier properties and high strain tolerance.
- The unique dissolution behavior of Ti ions at the nanoscale is key to improved ablation resistance.
- This research offers critical insights into the ablation mechanisms of Ti-containing multicomponent UHTCs.
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