AZ91 마그네슘 합금의 플라즈마 전해산화 피막 형성 및 물성에미치는 0.1 M NaOH + 0.05 M NaF 용액 중 Na2SiO3 농도의 영향
Formation behavior and properties of PEO films on AZ91 Mg alloy in 0.1M NaOH + 0.05 M NaF solution containing various Na2SiO3concentrations
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Effects of Na2SiO3 concentration added into 0.1 M NaOH + 0.05 M NaF solution on the formation behavior and properties of PEO films on AZ91 Mg alloy were investigated under 1200 Hz of alternating current (AC) by voltage-time curves, in-situ observation of arc generation behavior and measurements of film thickness, surface roughness and micro vickers hardness. In the absence of Na2SiO3 in the 0.1 M NaOH + 0.05 M NaF solution, about 4 ㎛thick PEO film was formed within 1 min and then PEO film did not grow but white spots were formed by local burning. Addition of Na2SiO3 up to 0.2 M caused more increased formation voltage and growth of PEO film with uniform generation of arcs. Addition of Na2SiO3 from 0.2 M to 0.4 M showed nearly the same voltage-time behavior and uniform arc generation. Addition of Na2SiO3 more than 0.5 M resulted in a decrease of formation voltage and non-uniform arc generation due to local burning. PEO film growth rate increased with increasing added Na2SiO3 concentration but maximum PEO film thickness was limited by local burning if added Na2SiO3 concentration is higher than 0.5 M. Surface roughness of PEO film increased with increasing added Na2SiO3 concentration and appeared to be proportional to the PEO film thickness. PEO film hardness increased with increasing added Na2SiO3 concentration and reached a steady-state value of about 930 HV at more than 0.5 M of added Na2SiO3 concentration.
Abstract
Effects of Na2SiO3 concentration added into 0.1 M NaOH + 0.05 M NaF solution on the formation behavior and properties of PEO films on AZ91 Mg alloy were investigated under 1200 Hz of alternating current (AC) by voltage-time curves, in-situ observation of arc generation behavior and measurements of film thickness, surface roughness and micro vickers hardness. In the absence of Na2SiO3 in the 0.1 M NaOH + 0.05 M NaF solution, about 4 ㎛thick PEO film was formed within 1 min and then PEO film did not grow but white spots were formed by local burning. Addition of Na2SiO3 up to 0.2 M caused more increased formation voltage and growth of PEO film with uniform generation of arcs. Addition of Na2SiO3 from 0.2 M to 0.4 M showed nearly the same voltage-time behavior and uniform arc generation. Addition of Na2SiO3 more than 0.5 M resulted in a decrease of formation voltage and non-uniform arc generation due to local burning. PEO film growth rate increased with increasing added Na2SiO3 concentration but maximum PEO film thickness was limited by local burning if added Na2SiO3 concentration is higher than 0.5 M. Surface roughness of PEO film increased with increasing added Na2SiO3 concentration and appeared to be proportional to the PEO film thickness. PEO film hardness increased with increasing added Na2SiO3 concentration and reached a steady-state value of about 930 HV at more than 0.5 M of added Na2SiO3 concentration.
참고문헌 (12)
- Carsten Blawert, "Anodizing Treatments for Magnesium Alloys and Their Effect on Corrosion Resistance in Various Environments", Advanced Engineering Materials 8, 6, pp.511~533 (2006)
- C. E. Barchiche, "A better understanding of PEO on Mg alloys by using a simple galvanostatic electrical regime in a KOH–KF–Na3PO4 electrolyte", Surface and Coatings Technology, 205, pp.4243~4248 (2011)
- J. Liang, "Electrochemical corrosion behaviour of plasma electrolytic oxidation coatings on AM50 magnesium alloy formed in silicate and phosphate based electrolytes", Electrochimica Acta, 54, pp.3842~3850 (2009)
- R. Arrabal, "Corrosion behaviour of a magnesium matrix composite with a silicate plasma electrolytic oxidation coating", Corrosion Science, 52, pp.3738~3749 (2010)
- 문성모, "Effect of NaOH Concentration on the PEO Film Formation of AZ31 Magnesium Alloy in the Electrolyte Containing Carbonate and Silicate Ions", 한국표면공학회지, 50(5), pp.308~314 (2017), 한국표면공학회[DOI]
- Stojadinović, S., "Characterization of plasma electrolytic oxidation of magnesium alloy AZ31 in alkaline solution containing fluoride", Surface and Coatings Technology, 273, pp.1~11 (2015)
- Xijin Li, "Discovery of Al2O3particles incorporation mechanism in plasma electrolytic oxidation of AM60B magnesium alloy", Materials Letters, 86, pp.88~91 (2012)
- Xiaopeng Lu, "Formation of photocatalytic plasma electrolytic oxidation coatings on magnesium alloy by incorporation of TiO2 particles", Surface and Coatings Technology, 307, pp.287~291 (2016)
- Xiaopeng Lu, "Plasma electrolytic oxidation coatings on Mg alloy with addition of SiO2particles", Electrochimica Acta, 187, pp.20~33 (2016)
- 문성모, "AZ31 Mg합금의 PEO피막 형성거동에 미치는 인산나트륨 농도의 영향", 한국표면공학회지, 52(5), pp.265~274 (2019), 한국표면공학회[DOI]
- S. Moon, "Generation mechanism of microdischarges during plasma electrolytic oxidation of Al in aqueous solutions", Corrosion Science, 51, pp.1506~1512 (2009)
- 권두영, "인산 및 규산 이온이 포함된 수용액에서 AZ31 마그네슘 합금의 플라즈마전해산화 피막의 구조에 미치는 수산화나트륨 농도의 영향", 한국표면공학회지, 49(1), pp.46~53 (2016), 한국표면공학회[DOI]