Nondestructive methods, evaluation

Hauk, V and H Belmkeu Structural and Residual Stress Analysis by Nondestructive Methods- Evaluation, Application, Assessment, Elsevier Science. New York, NY, 1997. 

Two sections deal briefly with procedures for investigating the pathways used in biodegradation and biotransformation. They cover briefly the application of isotopes, and of nondestructive methods that include NMR, EPR, and x-ray analysis. They should be viewed in the wider context of procedures for evaluating the effectiveness of bioremediation that are covered in Chapter 13 and their application in Chapter 14. 

Many results have been reported since NIR has been applied as nondestructive method for food quality evaluation. Table 1 shows major applications of NIR to food. In the beginning, NIR was used for the analysis of grain such as wheat, soybean and rice. More recently, however, the method has been applied to wide areas including processed food, beverages, fruits and vegetables. 

This book consists of nine chapters. The second chapter provides an overview of the important thermodynamic and kinetic parameters of relevance to corrosion electrochemistry. This foundation is used in the third chapter to focus on what might be viewed as an aberration from normal dissolution kinetics, passivity. This aberration, or peculiar condition as Faraday called it, is critical to the use of stainless steels, aluminum alloys, and all of the so-called corrosion resistant alloys (CRAs). The spatially discrete failure of passivity leads to localized corrosion, one of the most insidious and expensive forms of environmental attack. Chapter 4 explores the use of the electrical nature of corrosion reactions to model the interface as an electrical circuit, allowing measurement methods originating in electrical engineering to be applied to nondestructive corrosion evaluation and... 

Quality control of BDD electrodes is essential and is performed both by nondestructive and destructive testing methods. Nondestructive methods are either routine methods performed on each electrode (Raman spectroscopy to evaluate sp3/sp2... 

Scanning acoustic microscopy (SAM) is an ideal nondestructive method for revealing internal flaws within materials or between material interfaces. SAM is extensively used in detecting voids, delamination, and other separations that can occur in adhesive-attached parts, especially after thermal cycling. SAM is particularly useful in the analysis or evaluation of many types of electronic parts, including ceramic and plastic-encapsulated ICs, plastic-encapsulated microcircuits (PEMs), hybrid micro-circuits, CSPs, PBGAs, and printed-wiring boards. 

Nondestructive methods of testing, inspecting, or evaluating a product utilize physical measurements that do not alter the condition or life of the product for its continued use. NDT and NDI are generally considered synonymous, with both being related to the use of measurement tools per specification and assessment against specified criteria. NDE and nondestructive characterization are terms intended to convey the use of nondestructive measurements for material condition, property, or state assessment, especially in a quantitative manner. For the purposes of the remainder of this chapter, the acronym NDT will be used to represent all these issues. 

Reliability of electronic devices is caused predominantly by failures which result from the latent defects created during the manufacture processes or during the operating life of the devices. A search for new nondestructive methods to characterise quality and predict reliability of vast ensembles became a trend in the last four decades (Saveli etal. 1984), (Hartler et al. 1992), (Vandamme 1994), (Hashiguchi et al. 1998). The most promising methods to provide a non-destructive evaluation are an analysis of the electron transport parameters. Experiments are based on the measurements of device VA characteristics, nonlinearity using the non-linearity index (NLl), electronic noise spectroscopy, electro-ultrasonic spectroscopy and acoustic emission. These ones apply to both active and passive components, i.e., bipolar devices and MOS structures, on one hand, and resistors and capacitors on the other. 

ASTM G 46, Practice for Examination and Evaluation of Ktting Corrosion, recommends that pitting corrosion be quantified by destructive methods (metaUographic or by machiiung) or by nondestructive methods (micrometer or microscopical measurements). A standard rating chart for pits is included in ASTM G 46. 

There have been numerous efforts to inspect specimens by ultrasonic reflectivity (or pulse-echo) measurements. In these inspections ultrasonic reflectivity is often used to observe changes in the acoustical impedance, and from this observation to localize defects in the specimen. However, the term defect is related to any discontinuity within the specimen and, consequently, more information is needed than only ultrasonic reflectivity to define the discontinuity as a defect. This information may be provided by three-dimensional ultrasonic reflection tomography and a priori knowledge about the specimen (e.g., the specimen fabrication process, its design, the intended purpose and the material). A more comprehensive review of defect characterization and related nondestructive evaluation (NDE) methods is provided elsewhere [1]. 

F.A. Reed, T. Batzinger, R.W. Reed, and S. Jonsson. Porosity measurement of composites using attenuation methods. Review of Progress in Quantitative Nondestructive Evaluation, 12, 1993. 

The objective ia any analytical procedure is to determine the composition of the sample (speciation) and the amounts of different species present (quantification). Spectroscopic techniques can both identify and quantify ia a single measurement. A wide range of compounds can be detected with high specificity, even ia multicomponent mixtures. Many spectroscopic methods are noninvasive, involving no sample collection, pretreatment, or contamination (see Nondestructive evaluation). Because only optical access to the sample is needed, instmments can be remotely situated for environmental and process monitoring (see Analytical METHODS Process control). Spectroscopy provides rapid real-time results, and is easily adaptable to continuous long-term monitoring. Spectra also carry information on sample conditions such as temperature and pressure. 

Acoustic emission (AE) technique, in nondestructive evaluation, 17 425 Acoustic fields, filtration and, 11 324 Acoustic methods, of emulsion characterization, 10 128 Acoustic microscope, 16 505... 

Macro visual examination is done with the unaided eye or low power (up to 2 OX) magnification. An item may need to be cleaned prior to examination. Fracture origins and location of samples to be removed for further analysis are determined by macro visual examination. Nondestructive evaluation methods may be necessary for more accurate determinations (see Step 4). 

Corrosion detection plays an important role in any corrosion control program. Most of the methods employ nondestructive test methods and include hydrogen evaluation, radiography, dynamic pressure, corrosion probes, strain gauges and eddy current measurements. Of these, the methods employed in cooling tower practice are hydrogen evaluation and corrosion probes. 

Keywords method of visualization, acoustic microscopy, subsurface layers, nanopore density, elastic-mechanical steel parameters, nondestructive evaluation. 

The technique used in the characterization of the flaws in the sample depends upon whether the flaw is on the surface or in the interior of the sample. Some of the common methods used in the nondestructive evaluation of the flaws are noted below ... 

The indirect analytical nondestructive evaluation methods of interest are thermal analysis, finite element stress analysis, strain gauging, photoelasticity and brittle coatings. 

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