30 research outputs found
R. Bruce Thompson: Making a difference to safety and the NDE community
No full textAt the 2011 QNDE conference and at a special symposium at Iowa State University in October, we paid tribute to a friend, a mentor, and a colleague, R, Bruce Thompson. In several presentations, we heard of the contributions that Bruce made to Iowa State University and the Ames Laboratory.Copyright 2012 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.
This article appeared in AIP Conference Proceedings 1430 (2012): 9–12 and may be found at http://dx.doi.org/10.1063/1.4716209.</p
Flourescent penetrant inspection—cleaning study update
No full textFluorescent penetrant inspection (FPI) is widely used in the aviation industry and other industries for surface‐breaking crack detection. As with all inspection methods, adherence to the process parameters is critical to the successful detection of defects. There is variety of lubricants and surface coatings used in the aviation industry which must be removed prior to FPI. Before the FPI process begins, components are cleaned using a variety of cleaning methods which are selected based on the alloy and the soil types which must be removed. It is also important that the cleaning process not adversely affect the FPI process. From the first three phases of this project it has been found that a hot water rinse can aid in the detection process when using this nondestructive method.Copyright 2009 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.
This article appeared in AIP Conference Proceedings, 1096 (2009): 549–554 and may be found at: http://dx.doi.org/10.1063/1.3114303.</p
Feasibility Study for Detection and Quantification of Corrosion in Bridge Barrier Rails
No full textThree non-destructive technologies were evaluated for their abilities to detect and quantify corrosion damage in reinforcing steel used in bridge barrier rails.</p
Effect of hydrogen, deuterium and oxygen on the anelastic properties of refractory alloys
No full textThe effect of hydrogen, deuterium and oxygen on the anelastic properties of V, Nb and V-Nb alloys were examined. Activation parameters were obtained for the oxygen Snoek peak in V and Nb with various hydrogen concentrations. Hydrogen was found not to affect these oxygen relaxation parameters. Thus no interaction of oxygen with hydrogen occurs in the pure metals. Measurement of the hydrogen Snoek peak and the deuterium Snoek peak in V-Nb alloys also fed to determination of activation parameters for these interstitials that· are consistent with those found by diffusion measurements in this same alloy series. An isotope effect was observed. In addition, oxygen was found not to affect the relaxation of the hydrogen in the V-Nb alloys, indicating that the oxygen-hydrogen interaction in the alloys is also negligible.</p
The Iowa Demonstration Laboratory for NDE Applications — A New Approach to NDE Technology Transfer
No full textNondestructive evaluation plays an extremely important role in a number of the typically large, high-tech industries such as aerospace, nuclear, automotive, and petroleum. These industries and the federal government have made substantial investments to develop the equipment and perfect the various inspection techniques. With this substantial investment in the technology, there are many NDE tools currently available for transfer to the general manufacturing community. These tools are becoming increasingly important as companies, large and small, strive to improve product quality in order to increase customer satisfaction and maintain their particular market share.</p
Nondestructive Methods for Determination of Mechanical Properties of Aluminum and Titanium Alloys
No full textIn general, the mechanical properties of an alloy are determined by the microstructure that results from the alloy’s thermo-mechanical history. The thermo-mechanical path in alloy processing is chosen to take advantage of a least one of several strengthening mechanisms such as grain size, dispersion strengthening or dual phase structures. Optimization of an alloy’s strength is accomplished by control of the microstructure which determines the operative strengthening mechanism. Therefore NDE techniques sensitive to microstructural changes should prove useful in detecting mechanical property differences. In this work, various thermo-mechanical treatments have been used on aluminum and titanium alloys to provide a wide range of mechanical properties. From the results obtained it is concluded that selection of an NDE detection plan depends on the alloy’s thermo-mechanical history and will vary with alloy system.</p
Pod of ultrasonic detection of synthetic hard alpha inclusions in titanium aircraft engine forgings
No full textThe probability of detection (POD) of inspection techniques is a key input to estimating the lives of structural components such as aircraft engines. This paper describes work conducted as a part of the development of POD curves for the ultrasonic detection of synthetic hard alpha (SHA) inclusions in titanium aircraft engine forgings. The sample upon which the POD curves are to be based contains four types of right circular SHAs that have been embedded in a representative titanium forging, as well as a number of flat bottomed holes (FBHs). The SHAs were of two sizes, #3 and #5, with each size including seeds with nominal nitrogen concentrations of both 3 and 17 wt. %. The FBHs included sizes of #1, #3, and #5. This discreteness of the data poses a number of challenges to standard processes for determining POD. For example, at each concentration of nitrogen, there are only two sizes, with 10 inspection opportunities each. Fully empirical, standard methodologies such as versus a provide less than an ideal framework for such an analysis. For example, there is no way to describe the beam limiting effect whereby the signal no longer increases the flaw grows larger than the beam, one can only determine POD at the two concentration levels present in the block, and confidence bounds tend to be broad because of the limited data available for each case. In this paper, we will describe strategies involving the use of physics‐based models to overcome these difficulties by allowing the data from all reflectors to be analyzed by a single statistical model. Included will be a discussion of the development of the physics‐based model, its comparison to the experimental data (obtained at multiple sites with multiple operators) and its implications regarding the statistical analysis, whose details will be given in a separate article by Li et al. in this volume.Copyright 2011 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics.
This article appeared in AIP Conference Proceedings 1335 (2011): 1533–1540 and may be found at http://dx.doi.org/10.1063/1.3592112.</p
