CRAZING (MACRO CRACKS) IN HARD CHROME PLATING

[mands]

Can anyone please give me some information on possible causes for crazing on hard chrome plating (macro cracking).
I believe that high temperatures caused by grinding/polishing and pre-treatment of substrate are favourites.

The substrate is 17-4PH.

Thanks
Mandy

 

[mcguire]

Mandy, if you're still interested in this question,the reason is that as-plated chromium builds up very high residual stress in tension and self cracks when it is thick enough to reach the tensile strength.