gpab
Mechanical
- Feb 1, 2016
- 1
I am working on a tribometer for my capstone engineering project. The goal is to diagnose and eliminate the "contaminated" debris on the counter-face. Our motors have about 2 rpm difference which causes the 1/4" dia. sample to rub in an elliptical pattern resulting in a square wear surface. The issue is that the counter-faces are being discolored (oxidation?) and in some instances the sample actually is scratching the surface.
Two of the samples in the results I am uploading were UHMW-PE GUR 4150 and one sample (the one with notably darker and finer debris) is nylon.
The counter-faces are both stainless steel polished to 1200 grit sandpaper.
The pressure on each pneumatic air cylinder is 1.5 MPa.
This specific test ran 16 hours.
The samples were prepared in a compression mold in an oven at 400F.
I'm uploading a brief video to show how the machine works.
My main question is: Why are the counter-faces and debris being discolored. We expect the stainless steel to remain polished and the debris to be the same color as the untested samples.
(I apologize for my reflection on the counter-faces in the pictures)
Two of the samples in the results I am uploading were UHMW-PE GUR 4150 and one sample (the one with notably darker and finer debris) is nylon.
The counter-faces are both stainless steel polished to 1200 grit sandpaper.
The pressure on each pneumatic air cylinder is 1.5 MPa.
This specific test ran 16 hours.
The samples were prepared in a compression mold in an oven at 400F.
I'm uploading a brief video to show how the machine works.
My main question is: Why are the counter-faces and debris being discolored. We expect the stainless steel to remain polished and the debris to be the same color as the untested samples.
(I apologize for my reflection on the counter-faces in the pictures)