Profilometry information

Laser-based profilometry systems have also been adapted for unique applications in nuclear power generating plants. Applications where quantitative information with regard to surface condition for mechanisms such as surface pitting and flow-assisted corrosion are candidates for this NDT method. 

To characterize the overall appearance of a coating system mainly two different techniques are used in the automotive and paint industry. The mechanical profilometry yields a detailed information of the topography so that substrate influences and other effects on the final coating appearance can be described. These methods, in the past mainly used for coated steel substrates, were demonstrated showing typical examples of coatings for plastics. The optical method (wave-scan) yielded similar results. 

Surface roughness measurement can be characterized using either quantitative or qualitative methods. Qualitative techniques include optical appearance such as the reflectivity of a surface or the strength of the machining lay as well as dragging a thumbnail across the surface as a crude tactile sensor. Quantitative analysis has evolved from simple two-dimensional profilometry to more advanced three-dimensional area analysis where information regarding surface structure can be easily obtained. 

Dispensing defects can be detected by visual inspection or automated inspection techniques. Such automated techniques include those based on visible light images as well as laser profilometry that determines the actual volume of the adhesive or solder paste deposit. However, inspection slows the process assembly line. The more joints that are selected for inspection (that is, not aU joints need to be inspected) and the greater the information detail required from of the inspection results (referring to the height profilometry data collection), the longer the delay in the process flow. 

To obtain more quantitative information about the differences in the surface topographies of the PS layers with different polymer fillers, optical profilometry images were obtained for the most superhydrophobic, i. e., the M1E4H10X sample (Figure 15.7 a)). The roughness parameters of the surfaces are listed in Table 15.2. The dominant feature on the surface is a microstructure but as shown in Figure 15.7 b) a nanostructure is also present on microstructure protrusions. It is helpful if the air is trapped beneath the water droplet as it causes an increase of the contact angle up to 150°. 

A large amount of experience has accumulated in Russia on the irradiation behaviour of wrappers made of EP-450 steel more than 400 subassemblies with EP-450 wrappers have been irradiated in BN-600 [7.26] to a maximum dose of 94 dpa. Valuable experience on EP-450 wrapper irradiation was gained also in the former USSR in BN-350, the peculiarity of this reactor being low inlet sodium temperature (280°C). These irradiations showed the high dimensional stability of EP-450 steel. Profilometry of a large number of wrappers in a water pool produced the following information [7.27, 7.28] ... 

Although this method is not commonly used outside of the research environment, it does provide absolute overall sputter yield information (overall, because this includes the effects of ion implantation if apparent), a fact realized as the mass removed is measured. In addition, this can be useful in cases where neither stylus profilometry nor optical profilometry is applicable. Disadvantages associated with this method lie in the fact that this does not reveal the condition of the initial surface nor the crater base formed, both of which are important if high-depth resolution is required. Extreme care must be employed when carrying out such measurements. 

SIMS studies of these same films, however, did add useful information. The film thicknesses were too low to be able to use a high-current Cs primary beam for depth profiling. An Ar beam was used instead at low currents, which would not have introduced many chemical perturbations into the film. The results of such profiling are shown in Figs. 19a-c for samples of alloy A after exposures in pH 10 solution at the corrosion potential for periods of 3, 12, and 24 h. The intensities of the oxide secondary ions NiO" and CuO" are shown as functions of equivalent sputter time. The depths profiled in these instances were so shallow that it was impossible to gauge them by profilometry thus only the product of sputter time and current density is given on the abscissa. As before, the RSFs for the two ions are considered to be approximately equal. 

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