Journal of the Microelectronics and Packaging Society (마이크로전자및패키징학회지)

The Korean Microelectronics and Packaging Society (한국마이크로전자및패키징학회)
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Effects of PEO Conditions on Surface Properties of AZ91 Mg Alloy

PEO 처리조건에 따른 마그네슘 합금 AZ91의 표면특성변화에 관한 연구

  • Park, Kyeong-Jin (Dept. of Materials Science and Engineering, Hongik University) ;
  • Jung, Myung-Won (Dept. of Materials Science and Engineering, Hongik University) ;
  • Lee, Jae-Ho (Dept. of Materials Science and Engineering, Hongik University)
  • 박경진 (홍익대학교 신소재공학과) ;
  • 정명원 (홍익대학교 신소재공학과) ;
  • 이재호 (홍익대학교 신소재공학과)
  • Received : 2010.09.17
  • Accepted : 2010.09.28
  • Published : 2010.09.30
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Abstract

Mg alloys have been used in automobile industry, aerospace, mobile phone and computer parts owing to low density. However, they have a restricted application because of low mechanical and poor corrosion properties. Thus, improved surface treatments are required to produce protective films. Environmental friendly Plasma Electrolytic Oxidation(PEO) was used to produce protective films on magnesium alloys. PEO process is combined electrochemical oxidation with plasma treatment in the aqueous solution. In this study, the effects of applied voltage and applied current on the surface morphologies were investigated. Also, the effects of Direct Current(DC) and Pulse Current(PC) were compared. PC and constant current control gave the dense coating on the Mg alloy. The potentiodynamic polarization tests were carried out for the analysis of corrosion properties of specimens. The surface hardness was 5 times higher than that of untreated AZ91D.

마그네슘 합금은 낮은 밀도를 가지는 장점을 이용하여 자동차, 항공, 이동전화, 컴퓨터 등에 많이 쓰이고 있으나 기계적 강도가 낮고 내부식성이 좋지 않아 사용이 제한되었다. 마그네슘 합금 표면에 내식성 산화층을 형성하기 위하여 환경 친화적인 전해 플라즈마 산화법(PEO)을 연구에 사용하였다, PEO법은 수용약 중에서 플라즈마를 발생시켜 전기화학적 산화막을 형성시키는 방법이다. 인가전압과 전휴가 산화피마에 미치는 영향에 대하여 고찰하였다, 또한, 직류와 펄스전류를 사용하여 결과를 분석하였다. 펄스전류를 사용하고 정전류법을 사용한 경우에 치밀한 산화막을 얻을 수 있었다, 부식특성 분석을 위하여 양극산화분극방법을 이용하였다. 표면의 강도는 처리전의 AZ9ID에 비하여 5배 이상 증가하였다.

Keywords

References

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