Journal of the Korean institute of surface engineering (한국표면공학회지)

The Korean Institute of Surface Engineering (한국표면공학회)
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The Effects of Drying Temperature on Chromate Treatment for Electroplated Zinc

전기 아연도금용 유색 크로메이트에 대한 건조 온도의 영향

  • Su-Byung Jeon (Department of Materials Science and Metallurgical Engineering, Kyungpook National University) ;
  • Ji-Won Choi (R&D Center, ILSUNG Plating Co. Ltd.) ;
  • Byung-Ki Son (R&D Center, ILSUNG Plating Co. Ltd.) ;
  • Injoon Son (Department of Materials Science and Metallurgical Engineering, Kyungpook National University)
  • 전수병 (경북대학교 금속신소재공학과) ;
  • 최지원 ((주)일성도금 기업부설연구소) ;
  • 손병기 ((주)일성도금 기업부설연구소) ;
  • 손인준 (경북대학교 금속신소재공학과)
  • Received : 2023.08.17
  • Accepted : 2023.10.24
  • Published : 2023.10.31
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Abstract

In this study, the effect of drying temperature on characteristics of the trivalent chromate film on electroplated zinc was investigated. An zinc-electroplated iron specimen with a thickness of 5 ㎛ was used for chromate treatment. Chromate treatment was conducted in a solution diluted 10 times from a mixture of Cr(NO3)3·9H20 360 g/L, Co(NO3)2·6H2O 60 g/L, Na2SO4 60 g/L, NH4F·HF 25 g/L, and NaOH 20 g/L. The zinc electroplated specimen was treated using the chromate solution with pH 2.0 at 25 ℃ for 60 s. Subsequently, chromate-treated samples were dried in an electric furnace for 2h with temperature varied from 25 to 125 ℃. The corrosion rate increased with the increase in the drying temperature, and the surface morphology of the chromate-treated film was observed using FE-SEM. When the drying temperature changed, the color of the chromate film changed from green to yellow, and the thickness of the film changed from 362 to 241 nm, respectively. Additionally, corrosion resistance was evaluated via a salt spray test.

Keywords

Acknowledgement

본 연구는 중소벤처기업부 2021년도 기술혁신개발사업(소부장전략)의 지원사업으로 수행되었습니다(과제번호:S3142840).

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