Etching degree

Fig. 3.58 Relationship of etching degree of potassium, m ignesium and calcium to the etching degree of iron...

Pig. 3.59 Relationship of weight percent of aluminium oxide etched from the precursor (related to the meiss of the precursor before etching) to the etching degree of iron. Total contents of AI2O3 in the precursors are marked on the right side of the cheirt area. For the catalysts KO and K4 the total content of AI2O3 (see Table 3.26) exceeds the scale of y-axis... 

A big concern in swimming pools is prevention of etching and scaling (ie, precipitation of CaCO ) which can be controlled by maintenance of a proper degree of saturation with respect to calcium carbonate. The calcium carbonate dissolution-precipitation equiUbrium is represented by ... 

The adherend metallurgy also indirectly determines the degree of smut buildup because the rate of smut formation is proportional to the etch rate [54J. For instance, the etch rate of A606 is four times greater than that of A514, due to differences in grain size, etc. As a result, a different etch treatment is required for each. In general, the roles of alloy and heat-treatment differences have not... 

Certain Inconel alloys have been used with varying degrees of success. Inconel 600 (70% Ni, 15% Cr, 15% Fe) has been employed because of its improved resistance to chloride-induced, SCC, but it has failed on occasions because of intergranular attack and general etch corrosion. 

Morphology of the cured samples was analyzed by SEM of the fractured samples etched with tetrohydrofuran (THE), which is a solvent for the rubber. Figure 11.24 shows the fracture surfaces of the PWE and PNE specimens. Whereas the PWE fracture surface presents an essentially homogeneous surface with only a few small voids present, small yet uniformly distributed cavities are seen in PNE samples. The PWE morphology is consistent with the high degree of intermolecular link between rubber and epoxy macromolecules. The PNE morphology indicates incomplete reaction between epoxy and rubber. 

This leads to an efficient and non-destructive in situ etch rate measurement technique which does not require any prior knowledge of film properties. The analysis can also be used to semi-quantitatively gauge the degree of "roughening" imparted to a polymer film surface during RIE processing. 

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