Journal of the Korean Society of Manufacturing Process Engineers (한국기계가공학회지)

The Korean Society of Manufacturing Process Engineers (한국기계가공학회)
권호 표지
DOI QR코드

DOI QR Code

Chromate Conversion Coating on 3D Printed Aluminum Alloys

3D 프린팅으로 제조한 알루미늄 합금의 크로메이트 코팅

  • Received : 2021.11.30
  • Accepted : 2021.12.25
  • Published : 2022.02.28
Download PDF
⟨ Previous Next ⟩

Abstract

The demand for metal 3D printing technology is increasing in various industries. The materials commonly used for metal 3D printing include aluminum alloys, titanium alloys, and stainless steel. In particular, for applications in the aviation and defense industry, aluminum alloy 3D printing parts are being produced. To improve the corrosion resistance in the 3D printed aluminum alloy outputs, a post-treatment process, such as chromate coating, should be applied. However, powdered materials, such as AlSi7Mg and AlSi10Mg, used for 3D printing, have a high silicon content; therefore, a suitable pretreatment is required for chromate coating. In the desmut step of the pretreatment process, the chromate coating can be formed only when a smut composed of silicon compounds or oxides is effectively removed. In this study, suitable desmut solutions for 3D printed AlSi7Mg and AlSi10Mg materials with high silicon contents were presented, and the chromate coating properties were studied accordingly. The smut removal effect was confirmed using an aqueous desmut solution composed of sulfuric, nitric, and hydrofluoric acids. Thus, a chromate coating was successfully formed. The surfaces of the aluminum alloys after desmut and chromate coating were analyzed using SEM and EDS.

Keywords

Acknowledgement

이 논문은 2021년도 정보통신산업진흥원의 3D프린팅 제조혁신 실증지원 사업을 통해 연구되었음.

References

  1. Aboulkhair, N. T., Simonelli, M., Parry, L., Ashcroft, I. and Tuck, C. H., "3D printing of Aluminium alloys: Additive Manufacturing of Aluminium alloys using selective laser melting," Progress in materials science, Vol. 106, pp. 100578, 2019. https://doi.org/10.1016/j.pmatsci.2019.100578
  2. NaokiTakata, N., Kodaira, H., Sekizawa, K., Suzuki, A., Kobashi, M., "Change in microstructure of selectively laser melted AlSi10Mg alloy with heat treatments," Materials Science and Engineering: A, Vol. 704, No. 17, pp. 218-228, 2017. https://doi.org/10.1016/j.msea.2017.08.029
  3. Mickelson, F. L. and Wilde, Jr, A. G., "Aluminum Alloy Deoxidizing-Desmutting Composition and Method," US Patent: US3448055A.
  4. Mehta, M. D. and Butkovsky, P. A., "Composition for desmutting aluminum," US Patent: US6407047B1.
  5. Gillespie, R. D., "Characterisation of aluminium alloys after HNO3/HG-NaOH-HNO3/HF pretreatment," Mater. Sci. Technol., Vol. 17, No. 10, pp. 1211-1221, 2001. https://doi.org/10.1179/026708301101509287
  6. Choo, S. T. and Choi, S. K., "Development of Nitric Acid Free Desmut Solution for the Aluminum Alloy in Alkaline Etching and Acid Desmut Processes," Clean Technol., Vol. 9, No. 2, pp. 57-61, 2003.