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Plating / Coating after Nitriding / Carburising

What effect do nitriding / carburising have on the adhesion of plated / coated layers (hard chrome / TiN / TiCN) etc. Does the hardening method (or indeed the hardness of the nitrided / carburised layer) cause any loss of adhesion? I would really appreciate any help on this subject.

Wayne Ward
- England
1999

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I remember seeing some papers on TiN deposition after nitriding given at the International Conference on Metallurgical Coatings and Thin Films (ICMC-TF). The conference proceedings are usually published in Surface and Coatings Technology. Check your local university engineering library -- they probably carry the journal.

Jim Treglio - scwineryreview.com
PVD Consultant & Wine Lover - San Diego,
California
1999

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Ion nitriding and carburizing are both acceptable pre hard chrome plating base metal treatments. However, suitable pre-plate surface requirements must be achieved to ensure proper adhesion of the hard chrome coating. The adhesion of the hard chrome coating is not effected by the hardness of the base material. However, a base material that is not hardened properly can cause the hard chrome coating to fail.

Regards.

Stephen C. Ward
- Canada
1999

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2000

As stated previously, the hardness of the Nitrided or Carburised surface is not a real concern with regard to adhesion. The main problem is the surface condition. Plasma thermochemical surface treatments are beneficial in that they can be carried out with a high degree of control of gas mixtures and limit or exclude any unwanted surface products such as Comound (white) layer in Nitriding.

However,even with this amount of control, in practice, it is advised to polish the surface prior to coating.

Richard Buster - Wolverhampton, United Kingdom