Micro hardness testing
Micro hardness testing
(OP)
I am trying to find a solution to somehow test the hardness of some very small parts. These parts a basically a 4" piece of 17-4 wire with a diameter of 0.010". There does not need to be any certified testing equipment needed. All that is needed is a way to quickly analyze the hardness of each part after an H900 heat treating process. A non-destructive test would be prefered, but a small sample to do some destructive tests on could be allowed.
Is there anyway some other measurement could be used to correlate to the hardness of the material without doing an indentation? One idea that has been thrown around is using some kind of torque or cantilever test to basically correlate stiffness to hardness. We have tried simply scratching the surface with a file, but it produced a lack of consistent visual feedback.
This a territory I have not ventured in yet so any suggestions would be greatly appreciated.
Is there anyway some other measurement could be used to correlate to the hardness of the material without doing an indentation? One idea that has been thrown around is using some kind of torque or cantilever test to basically correlate stiffness to hardness. We have tried simply scratching the surface with a file, but it produced a lack of consistent visual feedback.
This a territory I have not ventured in yet so any suggestions would be greatly appreciated.





RE: Micro hardness testing
If you shop around you can usually find them for less than $100 a set. Take each file, and see if it will actually file the wire sample. If the file is softer than the wire, then it won't mark the wire. Go to the next harder file. Eventually you will find one that will mark the wire. At that point you will know that the wire's hardness must fall between the hardness of the last two files you used. And the hardness for martensitic steels correlates with the ultimate tensile strength: http://www.mwsco.com/kb/articles/19990630e.htm
This would be my first thought. If you require more accurate results, a more sophisticated technique would be required.
Maui
www.EngineeringMetallurgy.com
RE: Micro hardness testing
RE: Micro hardness testing
RE: Micro hardness testing
RE: Micro hardness testing
RE: Micro hardness testing
If you built a little fixture to bend a piece around a pin. Once you are in the plastic deformation range the load will only be a function of the wire size and strength.
Maybe move the arm of the fixture with a peak recording torque device.
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