In this work, the ablation behavior of monolith ZrB2-30 vol%SiC (Z30S) composites were studied under various oxy-acetylene flame angles. Typical oxidized microstructures (SiO2/SiC-depleted/ZrB2-SiC) were observed when the flame to Z30S was arranged vertically. However, formation of the outmost glassy SiO2 layer was hindered when the Z30S was tilted. The SiC-depleted region was fully exposed to air with reduced thickness when highly tilted. Traces of the ablated and island type SiO2 were observed at intermediate flame angles, which clearly verified the effect of flame angle on the ablation of the SiO2 layer. Furthermore, the observed maximum surface temperature of the Z30S gradually increased up to 2,200 °C proving that surface amorphous silica was continuously removed while monoclinic ZrO2 phase began to be exposed. A proposed ablation mechanism with respect to flame angles is discussed. This observation is expected to contribute to the design of complex-shaped UHTC applications for hypersonic vehicles and re-entry projectiles.

Abstract
1. 서 론
2. 실험방법
    2.1. ZrB2-30 vol% SiC 복합체 제조
    2.2. 내산화/내삭마성 실험 및 평가
3. 결과 및 고찰
4. 결 론
Acknowledgement
References

• 이승용(한국과학기술원 신소재공학과) | Seung Yong Lee (Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology)
• 공정훈(한국과학기술원 신소재공학과) | Jung Hoon Kong (Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology)
• 송정환(한국과학기술원 신소재공학과) | Jung Hwan Song (Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology)
• 손영일(국방과학연구소) | Young Il Son (Agency for Defense Development)
• 김도경(한국과학기술원 신소재공학과) | Do Kyung Kim (Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology) Corresponding author