MAO법을 이용한 산화피막처리에서 질산염 전해액성분 첨가에 따른 AZ31합금의 표면코팅 특성

국문 초록 (Abstract)

MAO 법을 이용하여 전류밀도 4A/㎠조건에서 3종류의 전해액과 코팅시간에 따라 AZ31 마그네슘 합금을 산화 피막 처리하였다. 코팅시간이 길어짐에 따라 코팅층의 표면형상은 기공이 더욱 커지고, 표면에 균열이 발생하기도 하 였다. 또한 코팅시간이 길어짐에 따라 코팅층의 두께와 경도(HV)값은 증가하였다. AZ31합금의 코팅층 상들은 MgO, Mg₂SiO₄ 그리고 MgAl₂O₄ 산화물로 이루어졌다. 산화코팅된 AZ31합금을 5% NaCl 용액에서 168시간동안 염수분무실 험결과 우수한 내식성을 나타냈다.

다국어 초록 (Multilingual Abstract)

AZ31 Mg alloy were coated by Macro Arc Oxidation(MAO) with 3 types of electrolyte and various coating times at 4A/㎠. The Surface morphology of coatings became lager pores and surface crack initiated as the coating time increased. The thickness and micro-hardness of coatings increased as the coating time increased. also. The phase of coatings on AZ31 alloy consisted of MgO, Mg₂SiO₄ and MgAl₂O₄ oxides. The salt spray corrosion resistance of coated AZ31 alloys revealed excellent corrosion resistance in 5% NaCl solution for 168hr.

참고문헌 (Reference)

1 M.A. Gonzalez-nunez, 37 : 1763-1772, 1995

2 M.Shahid, 32 : 3775-3781, 1997

3 L.Chai, 50 : 3274-, 2008

4 S.S.Byeon, 204 : 3196-3199, 2010

5 "http://www.keronite.co.uk/"

6 J.A.Curran, "Prosisty in plasma electrolytic oxide coatings" 54 : 1985-1993, 2006

7 A.L Yerokhin, "Plasma electrolytic fabrication of oxide ceramic sufaced layers for tribotechnical purposes on Al alloys" 110 : 140-146, 1998

8 A.L.Yerokhin, "Plasma electrolysis for surface engineering" 122 : 73-93, 1999

9 Kai Wang, "Nitrogen inducing effect on preparation of AlON-Al2O3 coatings on Al6061 alloy by EPP" 205 : S11-S14, 2010

10 H.F.Guo, "Microstructure characteristic of ceramic coatings fabricated on mg alloys by MAO in alkaline silicate solutions" 252 : 7911-7916, 2006

11 A.A.Voevodin, "Characterization of wear protective Al-Si-O coatings formed on Al-based alloys by micro arc discharge treatment" 516 : 86-87, 1996

12 V.Brass, "Characterization of oxide films formed on mg-based WE43 alloy using AC/DC anodization in silicate solutions" 151 : B1-B10, 2004

13 C.Blawert, "Anodizing treatments for magnesium alloys and their effect on corrosion resistance in various environments" 8 : 511-, 2006