Posted by Gordon England (62.252.0.12) on 11:45:15 15/08/05
In Reply to:Re: Please help me measure hardness posted by Pham Vinh
: : : Hello everybody,
: : : I am doing research on CrN coatings. Unfortunately, the coating is very rough so I can not measure hardness by Vickers. Someone suggests to polish samples before carrying out measuring hardness, but I am not sure whether this method is correct or not.
: : : I would like to receive your advices.
: : : Thank you so much.
: : : Pham Vinh
: :
: : It is normal and necessary to prepare the surface to a good flat finish in order to measure the hardness impression via the microscope. Generally lighter testing loads (smaller impressions) require better finishing.
: :
: : What is the thickness of your coatings?
: :
: : Regards Gordon
:
: Thanks for your advices!
: The thickness of my coating is ~7.0 micron. I am so grateful if I recieve more advices from you!
: My best regards
: Pham Vinh
I think this will not be practical. Assuming a perfect surface to start with, the maximum testing load would be around 10g giving around a 3 micron diagonal of the indentation for a hardness around 2000 HV. You say the surface is very rough. If you polished the surface flat to enable hardness testing, you will probably find little or no coating remains.
Regards Gordon
Please go to the new Surface Engineering Forum as this old message board is a read only archive. Please copy and paste relevant information or link to this page if you wish to reactivate this thread on the new forum.
