Crystallization abrasion behavior

Furthermore, on scale-up the ratio of surface area to volume also changes and thus influences the temperature differences in heat transfer and seed formation, as well as the vapor velocity at the liquid surface in evaporative crystallization. In scale-up the energy introduced per unit volume is usually kept constant, and hence this specifies the stirring speed. This results in almost comparable conditions for the suspension of the solids and the abrasion behavior. 

It will be shown later that for real crystals the abrasion behavior determines the quality of the product, e.g., the particle size distribution and the particle shape. The abrasion behavior depends on the following physical crystal properties ... 

The very complex nature of the macroscopic and microscopic structures as they affect strength and the behavior of diamond abrasive/particles still requires extensive work to elucidate fully. However, from a crystallization point of view, gaining control over the crystallization behavior is the key to the production of optimal diamond abrasives. This, of course, may be achieved by choice and manipulation of the pressure/temperature conditions, source carbon structure and solvent/catalyst metal type, leading to control over nucleation and growth rates. 

For a very large proportion of polymeric materials in commercial use, mechanical properties are of paramount importance, because they are used as structural materials, fibers, or coatings and these properties determine their usefulness. Properties that also determine their utilization are compressive, tensile, and flexural strength, and impact resistance. Hardness, tear, and abrasion resistance are also of concern. In addition, polymers may be shaped by extrusion in molten state into molds or by deposition from solutions on various surfaces. This makes the flow behaviors in the molten state or in solution, the melting temperatures, the amount of crystallization, as well as solubility parameters important. 

Ozel [86] studied the abrasive wear behavior of liquid crystal polymer, 30% reinforced polyamide 4,6, and 30% glass fiber-reinforced polyphenylene sulfide engineering polymers at atmospheric conditions. Pin-on-disc arrangement wear tests were carried out at 1 m/s test speed and load values of 4,6, and 8 N. Test durations were for 50,100 m and 150 m sliding distances. 

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