The effect of NaOH concentration on the properties of electrolytic plasma processing (EPP) coating formed on AZ61A Mg alloy is studied. Various types of EPP were employed on magnesium alloy AZ61A in a silicate bath with different concentrations of NaOH additive. Analysis of the composition and structure of the coating layers was carried out using an Xray diffractometer (XRD) and a scanning electron microscope (SEM). The results showed that the oxide coating layer mainly consisted of MgO and Mg2SiO4; its porosity and thickness were highly dependent on the NaOH concentration. The Vickers hardness was over 900 HV for all the coatings. The oxide layer with 3 g/l of NaOH concentration exhibited the highest hardness value (1220 HV) and the lowest wear rate. Potentiodynamic testing of the 3 g/l NaOH concentration showed that this concentration had the highest corrosion resistance value of 2.04 × 105 Ωcm2; however, the corrosion current density value of 5.80 × 10−7 A/cm2 was the lowest such value.

1. 서 론
 2. 실험 방법
  2.1 전해 플라즈마 공정 조건
  2.2 산화물층의 미세구조 및 결정상 분석
  2.3 기계적 특성
  2.4 부식 특성
 3. 결과 및 고찰
  3.1 산화물층의 표면 및 단면 형상
  3.2 산화물층의 결정 구조
  3.3 산화물층의 경도 및 내마모성
  3.4 코팅층의 부식저항
 4. 결 론
 References

• 신성훈(창원대학교 신소재공학부) | Seong Hun Shin
• 정영승(창원대학교 신소재공학부) | Young Seung Jeong
• Zeeshan Ur Rehman(창원대학교 신소재공학부)
• 구본흔(창원대학교 신소재공학부) | Bon Heun Koo Corresponding author