부분 안정화 지르코니아의 레이저 피닝 효과

국문 초록 (Abstract)

레이저 피닝은 재료 표면에 압축잔류응력을 형성시켜 기계적 성질을 향상시키는 기술이다. 최근 레이저 피닝이 실리콘카바이드, 알루미나 등과 같은 고급 세라믹에 적용되는 사례들이 늘고 있으며, 본 연구에서는 부분 안정화 지르코니아에 레이저 피닝을 적용하였다. 실험을 위해서 소결 상태의 지르코니아에 일반적인 가공 공법인 다이아몬드 커팅 및 연마를 거친 샘플과, 이런 가공 공정에 의해 발생할 수 있는 표면의 기계적 성질 변화 가능성을 방지하기 위해 소결 후 추가적인 표면 가공을 거치지 않은 두 가지 샘플을 사용하였다. 표면의 기계적 물성 측정을 위해 두 샘플 모두 표면을 1mm 거칠기로 폴리싱하였다. 레이저 피닝은 Nd: YAG 레이저(파장=532nm, 펄스 폭= 8ns)를 사용하여 레이저 에너지 강도 및 중첩률을 변화시키면서 진행하였으며, 피닝 전후의 표면 경도, 잔류응력, 마찰마모특성 및 파괴인성을 비교하였다.

다국어 초록 (Multilingual Abstract)

Laser shock peening (LSP) is a surface treatment technique that improves mechanical properties by inducing compressive residual stress on the surface of solids. The application of LSP to advanced ceramics such as silicon carbide or alumina has been increasing. In this study, LSP of partially stabilized zirconia was investigated. The zirconia samples for LSP were produced by sintering, and then prepared differently such that one underwent typical diamond cutting and grinding, whereas the other one was kept as sintered. The surface of both types of samples were polished to an average roughness of 1 mm for surface property measurement. LSP was carried out using a Nd:YAG laser (wavelength = 532 nm, pulse duration = 8 ns) while varying the laser irradiance and overlap ratio. The surface hardness, residual stress, abrasion resistance, and toughness were compared before and after LSP.

목차 (Table of Contents)

• 초록
• Abstract
• 1. 서론
• 2. 실험
• 3. 결과 및 분석
• 4. 결론
• 참고문헌(References)

참고문헌 (Reference)

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