Micro-coarse surface

The coarseness of a surface and consequently the effect of surface treatment can be measured with a laser beam. In addition the surface is often investigated by means of various microscopic techniques. The nature of a surface can tell us something of the structure of the material. The information obtained depends on the treatment the area has undergone and the way in which the surface is examined. The researcher may want to determine how many phases there are present in the sample, how they are distributed throughout the sample or what the pores and the pores distribution are like. For these purposes many kinds of light and electron micros-copes are available. 

Fine particle technology has broad applications in medicine for both therapeutics and diagnostics. The most common use of finely dispersed systems occurs in oral products that contain poorly water-soluble active agents. Fine (micro or nano) particles have increased surface area per unit dose relative to coarse active agent particles. As a result, the fine particles have much more favorable dissolution kinetics in-vivo. This can lead to increases in oral bioavailability, reductions in food-effect-associated variability, and more i id absorption and onset of therapeutic action. Topical delivery of active agent particles can also be enhanced when they are formulated as finely dispersed systems. 

The picture (d) in figure 4 shows the micro- particle morphology of iron ore C6. With irregular particle morphology and micro-fine-grained aggregates, C6 has high specific surface area in the condition of coarse particle. 

The roughness of 99.5Z Al20 will be relatively fine, of the order of 10 micro inches CLA. That of 96Z AI2O3 may be as coarse as 20 micro inches CLA. Camber will usually be present sometimes to such an extent it may be observed by the naked eye. Surface defects will almost certainly be present in the form of burrs, pits and ridges varying with the quality of the tape production process. 

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