Hard particles in a metal matrix can be difficult to microstructurally prepare because of particle pull-out as well as excessive relief between the particles and the matrix. The key to preparation of metal matrix composites (MMC) is to minimize damage at each preparation stage. This includes sectioning with the appropriate diamond wafering blade and using the finest practical abrasive for initial grinding. Polishing with SIAMAT colloidal silica provides a chemical mechanical polishing (CMP) action which is the most effective means for eliminating both surface and subsurface damage. The combination of SIAMAT colloidal silica with DIAMAT polycrystalline diamond also produces the required surfaces finishes in a minimal amount of time.
SECTIONING
Diamond Wafering blade - medium grit / high concentration
MOUNTING
Castable Mounting with Epoxy or Acrylic resins
POLISHING
Abrasive/surface |
Lubricant |
Force/ sample |
Speed |
Time |
| 30 um DIAMAT diamond suspension on CERMESH Metal Mesh cloth | 5-10 lbs | 200/200 rpm |
Until plane | |
| 9 um DIAMAT diamond on POLYPAD polishing pad | 5-10 lbs | 200/200 rpm |
3 minutes | |
| 3 um DIAMAT diamond on TEXPAN polishing pad | SIAMAT colloidal silica | 5-10 lbs | 200/200 rpm |
3 minutes |
0.05 micron NANOMETER alumina on TRICOTE polishing pad |
|
5-10 lbs |
100/100 rpm |
1 minute |
 |
SiC particles in an Aluminum Matrix, 400X (DIC) |