Electron beam method

Drilhng. Glass is dtiUed with carbide or bonded-diamond dtiUs under a suitable coolant such as water or kerosene. Other drilling processes include a metal tube rotating about its axis (core drilling), an ultrasonic tool in combination with an abrasive slurry, or an electron beam. Tolerances less than 0.1 mm are readily obtained with diamond-core drilling and, if required, holes smaller than 25 )J.m-dia can be made with the electron-beam method. 

Overall a customer needs to know under what circumstances it is best to use either the electron-beam techniques of EDS and WDS or the X-ray technique of XRF for an analysis problem. If both are equally available, the choice usually resides in whether high spatial resolution is needed, as would be obtained only with electron-beam techniques. If liquids are to be analyzed, the only viable choice is XRF. If one s choice is to use electron-beam methods, the further decision between EDS and WDS is usually one of operator preference. That is, to commence study on a totally new sample most electron-beam operators will run an EDS spectrum first. If there are no serious peak overlap problems, then EDS may be sufficient. If there is peak overlap or if maximum sensitivity is desired, then WDS is usually preferred. Factored into all of this must be the beam sensitivity of the sample, since for WDS analysis the beam current required is lO-lOOx greater than for EDS. This is of special concern in the analysis of polymer materials. 

Systems using either gamma radiation from cobalt 60 or electron beams have been used for vulcanization. The electron beam method has been used for curing silicone rubbers. 

One- and two-dimensional nanodomain configurations have been engineered in LiNbOs, RbTi0P04 and RbTi0As04 bulk fe crystals by the developed hvafm and indirect electron beam methods for a new generation of photonic and acoustic devices. 

The electron beam method was developed in the late 1960s and uses a focused electron beam to vaporize the central portion of a metal sample. Despite the necessity of... 

Elemental Determination of Surfaces by Electron Beam Methods... 

There is a need to make a thin sample that represents the bulk without introducing defects into the thin sample. The sample is ideally less than 100 nm thick, of uniform thickness, and both mechanically stable and electrically conductive under the electron beam. Methods to be considered are electropolishing, ion beam thinning, and ultramicrotomy. 

Subjecting a metal surface to an intense beam of light, such as that from a laser, can cause electrons to be ejected from the metal. As in the case of the electron beam, a very small current flow can be induced. Again a vacuum is required (so that the ejected electrons can be measured before they collide with air molecules), though the vacuum requirement is less stringent than that for the electron beam technique. The resistance at which continuity measurements can be made is quite limited, as in the case of the electron beam. (See discussion of electron beam method in Sec. 39.9.1.) Again, test speed suffers due to product capacitance. No practical system has resulted from investigative work. 

Table 5.50 lists the main features of Raman microspectroscopy. Virtually any object which can be observed under a microscope can be analysed with Raman microscopy. Here, the usual constraints inherent in electron beam methods (vacuum, metallisation, etc.) are totally absent. Although micro-Raman spectrometers mainly use visible excitation, the confocal configuration almost eliminates fluorescence which falls outside of the focal volume. The focus area for visible lasers is <1 /xm, whereas the focus diameter for NIR lasers is 20 fim. 

Titaniuin and most titanium alloys can be welded by arc, spot, seam, flash, pressure, friction and electron beam methods. Procedures and equipment are generally similar to those used for welding austenitic stainless steel or aluminum. However, because titaniixm and titanium alloys are extremely reactive above 540 °C (1000 °F), precautions mvist be taken to shield the joint frnm air. No flux is used when welding titaniimi. 

Focused ion and electron beam methods have emerged as invaluable tools for producing nanoelectrodes and are particularly advantageous in the fabrication of ordered nanoelectrode arrays and assemblies where precision and scale-up are critical. In focussed ion-beam (FIB) milling, a finely... 

Radiation or electron-beam method (PEX-c) The formed tubing passes through a radiation chamber (electron beam or X-ray) that generates the cross-links. The cross-link is a C-C bond. 

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