Etching solution for T800

[Phdstudent]

Hi all
Iam new member here (and sorry 4 my bad english)

what is the etching solution for laser treated Hvof coating (T800 and T800 with different percentages of WC) on stainless steel 316L.PhD student
Thank you

[Gordon]

Hi Phdstudent

to the Surface Engineering Forum.

I've no experience of etching this particular coating. Normally most thermal spray coatings are not etched for metallography as most of the information needed can be gained from viewing just in the as-polished condition. The nature of thermal spray coatings tends to make etching very difficult and unpredictable. There are times however when etching can be useful for identifying features not resolved in the as-polished condition.

What specific features are you trying to reveal, that don't show with viewing in the as-polished condition?

I can only think of experimenting with etching solutions based around Kalings No2, Kellers and Murakami's. Electro-etching, heat tinting and careful use of relief polishing (mechanical etching) may also be worth considering. Note of caution please be very careful with many of these chemicals particularly if experimenting ( experience can be painful )

[Phdstudent]

Thank you Gordon for your replay

Actually, I wanna do etching to recognize the remelting area for (T800 Hvof coating) by laser, because, the borders for the remelting regions not clear.

Thank you again

Gordon Wrote:Hi Phdstudent

to the Surface Engineering Forum.

I've no experience of etching this particular coating. Normally most thermal spray coatings are not etched for metallography as most of the information needed can be gained from viewing just in the as-polished condition. The nature of thermal spray coatings tends to make etching very difficult and unpredictable. There are times however when etching can be useful for identifying features not resolved in the as-polished condition.

What specific features are you trying to reveal, that don't show with viewing in the as-polished condition?

I can only think of experimenting with etching solutions based around Kalings No2, Kellers and Murakami's. Electro-etching, heat tinting and careful use of relief polishing (mechanical etching) may also be worth considering. Note of caution please be very careful with many of these chemicals particularly if experimenting ( experience can be painful )