No, it is not necessary to paint or powder coat the coating afterwards. However, in doing so, when correctly applied, it can enhance the life of the coating further. As the colours of Metal Sprayed coatings are limited, a paint or powder coat layer on top of the Metal Sprayed layer is often used for decorative purposes.

Zinc Metal Sprayed Artwork with Paint Top Coat – Image provided courtesy of Ironic Art, Gatton QLD.
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