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Materials-based process tolerances for neutron generator encapsulation.

Description: Variations in the neutron generator encapsulation process can affect functionality. However, instead of following the historical path in which the effects of process variations are assessed directly through functional tests, this study examines how material properties key to generator functionality correlate with process variations. The results of this type of investigation will be applicable to all generators and can provide insight on the most profitable paths to process and material improvements. Surprisingly, the results at this point imply that the process is quite robust, and many of the current process tolerances are perhaps overly restrictive. The good news lies in the fact that our current process ensures reproducible material properties. The bad new lies in the fact that it would be difficult to solve functional problems by changes in the process.
Date: October 1, 2007
Creator: Berry, Ryan S.; Adolf, Douglas Brian & Stavig, Mark Edwin
Partner: UNT Libraries Government Documents Department

Noncontact material testing using laser energy deposition and interferometry

Description: A technique is described for the noncontact testing of materials using laser deposition to generate a stress pulse and interferometry to record the transient surface displacement. The dilatational wave speed can be measured and, in the particular case of rod or plate specimens, sufficient information can be obtained to evaluate the two elastic constants of an isotropic material. Several applications illustrating the advantages of the approach are summarized.
Date: February 6, 1978
Creator: Calder, C.A. & Wilcox, W.W.
Partner: UNT Libraries Government Documents Department

Operating Manual for the MTR, Section Two -- Exclusion Area, Materials Testing Reactor

Description: From summary: "This manual is designed for the purpose of clarifying operating procedures of the Materials Testing Reactor and its associated equipment. In assembling this manual a description of each item of equipment and its function is presented. In addition, the generally accepted method of operating the equipment and the best corrective measures concerning all emergencies that might be encountered are set forth herein. Descriptive drawings and written instructions pertaining to the equipment have been included to further clarify the manual."
Date: 1955
Creator: Phillips Petroleum Company. Atomic Energy Division.
Partner: UNT Libraries Government Documents Department

Characterization of nonstationary random processes

Description: Current methods for shock test specification and shock testing treat the shock environment as a deterministic source. The present study proposes to treat shock sources as nonstationary random processes. A model for a realistic nonstationary random process shock source is specified, and the effect of variation of parameters in the shock source is shown. A method for estimating the parameters of the random process is established, and some numerical examples show that the method yields reasonable results. The use of this model in shock testing is discussed.
Date: January 1, 1985
Creator: Paez, T.L.
Partner: UNT Libraries Government Documents Department

Preprocessing of PHERMEX flash radiographic images with Haar and adaptive filtering

Description: Work on image preparation has continued with the application of high-sequency boosting via Haar filtering. This is useful in developing line or edge structures. Widrow LMS adaptive filtering has also been shown to be useful in developing edge structure in special problems. Shadow effects can be obtained with the latter which may be useful for some problems. Combined Haar and adaptive filtering is illustrated for a PHERMEX image.
Date: November 1, 1978
Creator: Brolley, J.E.
Partner: UNT Libraries Government Documents Department

Accelerated screening methods for predicting lubricant performance in refrigerant compressors. Progress report, May 1, 1993--December 31, 1993

Description: As part of an overall testing program to identify more effective bench testers for screening oils for compressors, a comparison is made in this report between data obtained from a Falex specimen tester and those obtained from a high pressure tribometer (HPT). The Falex data were supplied by three compressor manufacturers. These data were mainly obtained by bubbling refrigerants through the oil, whereas, the data from the HPT are based on environmental (temperature and pressure) found in specific contacts in compressors. The same contact geometries and materials are used for both the Falex and the HPT tests. The main purpose of this comparison is to see if the controlled environment and the lower loads used with the HPT produces different rankings than that obtained from the Falex tests. In general, the results obtained from the HPT did not always correlate with each other and those obtained from the Falex tester. These findings are discussed in detail in this report.
Date: January 1, 1994
Creator: Cusano, C.
Partner: UNT Libraries Government Documents Department

Study of the relationships of three factors on errors in inspection

Description: Gaging errors can occur in any process of fabrication and inspection of product. There are two types of errors: (1) accepting product that should be rejected, and (2) rejecting product that should be accepted. Costs of these errors depend on how frequently they occur. The frequency of these errors (i.e., their probability of occurring) is a function of three factors: (1) specification limits (tolerance) of the feature being processed, (2) variability of the fabrication process, and (3) variability of the inspection process. With some basic assumptions, this report shows the likelihood of each type of gaging error for many combinations of these three factors. Thus, for example, with knowledge of the tolerance for a feature and an estimate of the variation of the fabricating process, a gage designer can objectively assess how critical his gaging repeatability is in terms of errors of inspection. This assessment should prove more cost effective than any rule of thumb such as ''gaging repeatability should be 10 percent of the feature tolerance''.
Date: April 1, 1977
Creator: Leete, Jr., R. S. & Lever, W. E.
Partner: UNT Libraries Government Documents Department

Versatile laser glass inspection and damage testing facility

Description: A test facility is described which detects small opaque inclusions in large transparent components by using a commercial laser which delivers high energy pulses to the test sample at moderate frequency in a small diameter beam. The sample is automatically scanned such that each point in the volume is irradiated with ten pulses at twice the inclusion damage threshold - an amount sufficient to cause visible damage at inclusion sites. This approach permits detection of opaque inclusions in the parts per trillion and lower concentration range. The specifics of the device design and its performance are discussed in the context of automatic inclusion inspection and mapping in large laser optics.
Date: January 17, 1986
Creator: Marion, J. E.; Greiner, G. J.; Campbell, J. H.; Chaffee, P. H.; Hildum, J. S.; Grens, J. Z. et al.
Partner: UNT Libraries Government Documents Department

Magnetic testing probe

Description: A cylindrical eddy current tube testing probe is disclosed. Current flow in dual electromagnetic coils separated by an eddy current sensing coil is so directed that magnetic fields of the electromagnet coils have components extending in opposite directions axially of the tested tube and components extending radially of the tube which add in the region of the eddy current sensing coil.
Date: July 7, 1981
Creator: Scott, G.W. & Chitwood, L.D.
Partner: UNT Libraries Government Documents Department

Image processing applications in NDE

Description: Nondestructive examination (NDE) can be defined as a technique or collection of techniques that permits one to determine some property of a material or object without damaging the object. There are a large number of such techniques and most of them use visual imaging in one form or another. They vary from holographic interferometry where displacements under stress are measured to the visual inspection of an objects surface to detect cracks after penetrant has been applied. The use of image processing techniques on the images produced by NDE is relatively new and can be divided into three general categories: classical image enhancement; mensuration techniques; and quantitative sensitometry. An example is discussed of how image processing techniques are used to nondestructively and destructively test the product throughout its life cycle. The product that will be followed is the microballoon target used in the laser fusion program. The laser target is a small (50 to 100 ..mu..m - dia) glass sphere with typical wall thickness of 0.5 to 6 ..mu..m. The sphere may be used as is or may be given a number of coatings of any number of materials. The beads are mass produced by the millions and the first nondestructive test is to separate the obviously bad beads (broken or incomplete) from the good ones. After this has been done, the good beads must be inspected for spherocity and wall thickness uniformity. The microradiography of the glass, uncoated bead is performed on a specially designed low-energy x-ray machine. The beads are mounted in a special jig and placed on a Kodak high resolution plate in a vacuum chamber that contains the x-ray source. The x-ray image is made with an energy less that 2 keV and the resulting images are then inspected at a magnification of 500 to 1000X. Some …
Date: January 1, 1980
Creator: Morris, R.A.
Partner: UNT Libraries Government Documents Department
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