|Monthly Tech-Tip |
The percentage of a material powder whose absolute particles are smaller than 20 microns.
The coarsest screen is at the top, the finest on the bottom. The top one has an opening of 425 microns (thus 425 micron and finer particles will pass through it, +425 micron particles will not). Its opening area is 180,000 square microns (425x425). Going downward, the openings have areas half that of the one above (thus, for the second, the opening area is 300x300=90,000 microns). Structural products industries, like brick, measure coarser particles than this, using 10-70 mesh. Using this series one can produce a standard measurement of the distribution of particle sizes in a material powder. The finer sieves (from 100-325) are only practical for wet processing (where the powder is water washed through the stack). In Insight-live the SIEV test (water washed) uses this series of sieves.
Average Particle Size (Microns)
% < 10 microns
% < 30 microns
Utlimate particles of ceramic materials are finer than can be measured even on a 325 mesh screen. These particles are the key players in the physical presence of the material.
Tests conducted to determine particle populations, sizes, shapes, densities, surface areas, etc.
|By Tony Hansen|
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