| The Role of Microstructure on Various Stages of the Very High Cycle Fatigue Behavior of an a + Beta Titanium Alloy, Ti-6Al-2Sn-4Zr-6Mo (Preprint) |
Oct 2011 |
8 pages |
| Authors:
C J Szczepanski; S K Jha; J M Larsen; J W Jones; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIRECTORATE
|
 | The very high cycle fatigue behavior (105-109 cycles) of Ti-6246 has been investigated using ultrasonic fatigue techniques. In this regime of fatigue (0.4-0.6deltaYS), only certain microstructural regions are susceptible to fatigue damage accumulation, and lifetimes are related to the distribution of fatigue critical microstructural neighborhoods. Three distinct categories of crystallographic crack initiation sites have been identified. Fatigue crack initiation and early growth is typified by a crystallographic facet formation process ... |
|
| Extensive Characterization of Cracking in As-fabricated Composite Ceramic Panels Via Ultrasonic and X-ray Computed Tomography Testing |
Aug 2011 |
22 pages |
| Authors:
William H Green; Raymond E Brennan; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| Decreasing the weight of protective systems, while minimizing the decrease in ballistic performance, is an ongoing goal of the Army. Ceramic materials are currently combined with other materials in these types of structures in order to decrease weight without losing ballistic performance. This includes structures in which the ceramic material is confined in some way or completely encapsulated. Confinement or encapsulation of ceramic material within a structure generally adds complexity ... |
|
| Molten Boron Phase-Change Thermal Energy Storage to Augment Solar Thermal Propulsion Systems |
22 Jul 2011 |
7 pages |
| Authors:
David Scharfe; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| Solar thermal propulsion offers a unique combination of high thrust and high specific impulse levels that can provide competitive advantages relative to traditional satellite propulsion systems. In order to enhance the functionality of this technology, thermal storage combined with a means of thermal-to-electric conversion is suggested, with the idea of providing a dual-mode power and propulsion system based on thermal energy. A system including boron phase change material for storing ... |
|
| The Role of Microtexture on the Fatigue Behavior of an alpha + beta Titanium Alloy, Ti-6Al-2Sn-4Zr-6Mo (Preprint) |
MAR 2011 |
|
| Authors:
J. M. Larsen; C. J. Szczepanski; S. K. Jha; J. W. Jones; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIR METALS CERAMICS AND NONDESTRUCTIVE EVALUATION DIV/METALS BRANCH
|
| The effect of microstructural heterogeneity, specifically regions of grains with similar crystallographic orientations, or microtexture, on the initiation and early growth of fatigue cracks from multiple micro-notches has been investigated in Ti-6246. Experiments were performed using ultrasonic fatigue techniques for two different microstructural conditions. Local texture surrounding micro-notches was found to influence micro-notch fatigue crack initiation in one of the microstructures. Fatigue crack initiation was least likely to occur from ... |
|
| Defect Identification in Composite Structures Using Enhanced Signal Analysis |
07 JAN 2011 |
29 pages |
| Authors:
Shen H. Lim; Tomonari Furukawa; VIRGINIA POLYTECHNIC INST AND STATE UNIV BLACKSBURG DEPT OF MECHANICAL ENGINEERING
|
| This project developed a new approach with theoretical and experimental framework to automatically and rapidly quantify invisible defects in a composite structure through enhanced analysis of data from ultrasonic non-destructive inspection methods. The objectives of this project were to develop rapid automated techniques to: Interrogate output from ultrasonic NDI equipment to identify the presence of defects, Identify the type of defect, in particular delamination, disbanding, foreign body inclusions and porosity ... |
|
| Modern Nondestructive Test Methods for Army Ceramic Matrix Composites |
Oct-2008 |
18 pages |
| Authors:
Douglas J Strand; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
|
| As composites have developed and matured, the nondestructive testing (NDT) methods needed to characterize and maintain them have also developed and matured. The purpose of this report is to examine the newer methods of NDT, which may be applicable to some of the new composite materials being used for U.S. Army applications. Ceramic matrix composites (CMC) are potentially good high-temperature structural materials because of their low density, high elastic moduli, ... |
|
| UH-60 BIM Blanket Tap Test Evaluation |
22 SEP 2007 |
2 pages |
| Authors:
NATIONAL CENTER FOR DEFENSE MANUFACTURING AND MACHINING LATROBE PA
|
| Corpus Christi Army Depot (CCAD), Corpus Christi, Texas, inspects the outer mold layer (OML) of the UH-60 Black Hawk helicopter rotor blades for voids and delaminations. This process requires inspection of the blade from fore to aft and from rotor to blade tip. The current inspection process requires a technician to perform a manual "Tap" test of the blade using a small, specialized hammer. During the tapping of the blade, ... |
|
| Structural Irregularity and Damage Evaluation Routine (SIDER) for Testing of the 1/2-Scale Corvette Hull Section Subjected to UNDEX Testing |
OCT 2005 |
33 pages |
| Authors:
Colin P. Ratcliffe; Roger M. Crane; NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD
|
| This effort entailed performing Structural Irregularity and Damage Evaluation Routine (SIDER) inspection of the entire GRP Hull of a 1/2-scale corvette mid-ship section after each of three underwater explosion (UNDEX) loadings. The SIDER testing was being used to rapidly interrogate the entire hull structure to identify the areas that had experienced structural degradation that manifested itself in a structural stiffness change. These SIDER results were then compared with the results ... |
|
| Laboratory Characterization of Fine Aggregate Cementitious Material |
JUL 2005 |
101 pages |
| Authors:
Erin M. Williams; Stephen A. Akers; Paul A. Reed; ENGINEER RESEARCH AND DEVELOPMENT CENTER VICKSBURG MS GEOTECHNICAL AND STRUCTURES LAB
|
| Personnel of the Geotechnical and Structures Laboratory, U.S. Army Engineer Research and Development Center, conducted a laboratory investigation to characterize the strength and constitutive property behavior of a fine aggregate cemented material (FACM). The FACM was designed to have a 34-MPa (5, 000-psi) unconfined strength and to contain no coarse aggregate. Forty-three mechanical property tests two hydrostatic compression tests (HC), four unconfined compression tests (UC), 16 triaxial compression tests (TXC), ... |
|
| Ultrasonic Wave Propagation in Thick, Layered Composites Containing Degraded Interfaces |
JUN 2005 |
|
| Authors:
Peter D. Small; MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF OCEAN ENGINEERING
|
 | The ultrasonic wave propagation of thick, layered composites containing degraded bonds is investigated. A theoretical one-dimensional model of three attenuative viscoelastic layers containing two imperfect interfaces is introduced. Elastic material properties and measured values of ultrasonic phase velocity and attenuation are used to represent E-glass and vinyl ester resin fiber-reinforced plastic (FRP) laminate, syntactic foam, and resin putty materials in the model. The ultrasonic phase velocity in all three materials ... |
|
| Large Area, Real-Time Inspection of Rocket Motors Using a Novel Handheld Ultrasound Camera |
12 MAR 2004 |
20 pages |
| Authors:
J. W. Gurney; M. E. Lasser; R. S. Lasser; J. P. Kula; D. C. Rich; IMPERIUM INC SILVER SPRING MD
|
| Phase I of this SBIR program sought to demonstrate the applicability of the Imperium ultrasound camera to the inspection of solid rocket motors (SRMs). Phase II of the program aimed at developing a prototype camera that could be used in either handheld or production settings. The prototype camera was tested to determine its level of performance, ability to detect typical flaws, and the potential time savings with its use. Results ... |
|
| Medical Ultrasound Technology Research and Development at the University of Washington Center for Industrial and Medical Ultrasound |
02 OCT 2003 |
18 pages |
| Authors:
Lawrence A. Crum; UNIV OF WASHINGTON SEATTLE APPLIED PHYSICS LAB
|
| This grant provided support to expand the scientific program and infrastructure at the University of Washington's Center for Industrial and Medical Ultrasound (CIMU). The many disparate facilities and technical capabilities available to CIMU staff and students were integrated and enhanced to provide a world-class, advanced research center for bioengineering development and graduate education in high-intensity, focused ultrasound (HIFU). This included leveraging of overall research in understanding of acoustic hemostasis and ... |
|
| Nondestructive Evaluation (NDE) Technology Initiative Program (NTIP). Delivery Order 0032: MAUS Implementation for Corrosion/Crack Detection in Wing Structure - Phase III |
30 SEP 2003 |
48 pages |
| Authors:
Donald D. Palmer Jr.; Nancy L. Wood; BOEING CO ST LOUIS MO PHANTOM WORKS
|
| This report summarizes the results of Phase III of the "MAUS implementation for Corrosion/Crack Detection in Wing Structure" program. During Phase III, all system optimization activities, including hardware and software enhancements to improve ultrasonic pulse-echo data collection and data interpretation, were completed. Also completed was the B-52 upper wing spanwise splice inspection process development and validation. The automated second layer ultrasonic inspection procedure developed was designed to rapidly detect fatigue ... |
|
| Fundamental Studies: Inspection Properties for Engine Titanium Alloys |
DEC 2002 |
159 pages |
| Authors:
F. J. Margetan; M. Gigliotti; L. Brashe; W. Leach; IOWA STATE UNIV AMES CENTER FOR NONDESTRUCTIVE EVALUATION
|
| Titanium alloys are widely used in critical rotating components for jet engine applications. Because of the important role they play in overall flight safety, it is important that the components be free of defects which can lead to failure. In light of this requirement, titanium components are typically inspected several times during the production process. One of the methods used is ultrasonic inspection. However, titanium is an ultrasonically noisy material ... |
|
| Advanced Nondestructive Evaluation (NDE) Methods. Work Unit Directive (WUD) 40 |
OCT 2002 |
9 pages |
| Authors:
AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIRECTORATE
|
| This bibliography consists of a compilation of publications from 1994-1999. |
|
| Nondestructive Evaluation (NDE) Technology Initiatives. Delivery Order 0021: Application of an Electrochemical Fatigue Sensor (EFS) Borescope System for Military Turbine Engine Assessment |
OCT 2002 |
35 pages |
| Authors:
R. Krupa; R. Tillinghast; T. Root; MATERIALS TECHNOLOGIES INC DBA TENSIODYNE SCIENTIFIC CORP LOS ANGELES CA
|
| The objective for this project was to improve the United States Air Force's capability to perform fatigue assessment of military aircraft engines through the application of four nondestructive technologies: eddy current inspection, ultrasonic inspection, visual inspection, and the electrochemical fatigue sensor (EFS). EFS is a relatively new technology; the other three inspection methodologies are well established and widely accepted means of component inspection. A 6-mm-diameter inspection borescope, capable of delivering ... |
|
| Research and Educational Activities at the FAST Center for Structural Integrity of Aerospace Systems |
03 SEP 2002 |
220 pages |
| Authors:
Roberto A. Osegueda; Carlos M. Ferregut; TEXAS UNIV AT EL PASO FAST CENTER FOR STRUCTURAL INTEGRITY OF AEROSPACE SYSTEMS
|
| This report describes the technical research activities that were carried out at the Future Aerospace Science and Technology (FAST) Center for Structural Integrity of Aerospace Systems, the University of Texas at El Paso, under findings from the US Air Force Office of Scientific Research. Also included is a brief description of the efforts to educate minority scientists and engineers. The technical mission was to conduct basic research to contribute to ... |
|
| Overview of Mathematical Modeling in Nondestructive Evaluation (NDE) |
SEP 2002 |
|
| Authors:
John C. Aldrin; NONDESTRUCTIVE TESTING INFORMATION ANALYSIS CENTER AUSTIN TX
|
| This report presents a broad overview of mathematical modeling in nondestructive evaluation (NDE). The primary emphasis is to expand the review of NDE modeling literature covered by previous general works. To provide a starting point for researchers and engineers, the discussions and references include multiple modeling approaches (analytical, asymptotic, and numerical) for a variety of NDE techniques. A second emphasis for this report is to present the pertinent modeling software ... |
|
| Nondestructive Inspection (NDI) Through High-Velocity Oxygen Fuel (HVOF) Thermal Spray Coatings. Delivery Order 0001: Nondestructive Evaluation Exploratory Development for Air Force Systems |
MAY 2002 |
26 pages |
| Authors:
Noel Tracy; Sandra Davis; John Brausch; UNIVERSAL TECHNOLOGY CORP DAYTON OH
|
| High Velocity Oxygen Fuel (HVOF) thermal spray coatings are the leading candidates to replace electrolytic hard chrome (EHC) coatings on critical high strength steel components such as aircraft landing gear. HVOF qualification as an acceptable replacement for hard chrome plating has not been fully demonstrated, particularly for fatigue-sensitive aircraft components. One area lacking is the ability to inspect through these coatings for substrate damage. Three nondestructive inspection (NDI) techniques were ... |
|
| New Signal Processing Techniques to Interpret, Track and Predict Damage in Aircraft Materials and Structures |
31 OCT 2001 |
10 pages |
| Authors:
Kevin T. Kornegay; CORNELL UNIV ITHACA NY DEPT OF THEORETICAL AND APPLIED MECHANICS
|
| This program of research had as its focus the development and implementation of a synergistic measurement system in which the sensing and processing of ultrasonic signals comprise an autonomous and intelligent measurement system capable of processing a diversity of sensory signals to model, forecast and possibly even control the condition of a material or a structure with respect to its performance. The intended application was to a procedure by which ... |
|
| Synchronized Measurements of Maximum Blood Flow Velocities in Carotid, Brachial and Femoral Arteries, and ECG in Human Posture Changes |
25 OCT 2001 |
|
| Authors:
Y. Hirao; T. Kuroda; D. Zhang; Y. Kinouchi; H. Yamaguchi; TOKUSHIMA UNIV (JAPAN)
|
| A system was developed to measure maximum blood flow velocity in three arteries simultaneously during exercise (i.e., sitting to standing and standing to sitting) using an ultrasonic Doppler technique. The ultrasonic Doppler technique can measure the dynamics of blood flow in arteries that exist deep within the human body. Since the position of the arteries in relation to the probes would change rapidly during the posture changes, conventional ultrasonic systems ... |
|
| Non-Invasive Ultrasonic Diagnosing and Monitoring of Intracranial Pressure/Volume |
OCT 2001 |
74 pages |
| Authors:
Aloyzas Petrikas; VITTA CORP BETHEL CT
|
| Objectives are to verify the innovative concepts of non-invasive intracranial pressure (ICP) absolute value measurement and non-invasive cerebrovascular autoregulation continuous monitoring, to prove the design concepts and to perform the limited clinical trials of the new prototype devices. These devices were designed and successfully tested. Slow intracranial and ABP wave correlation methodology was used for cerebrovascular autoregulation monitoring. Prototype of non-invasive slow wave monitor has been used together with invasive ... |
|
| Sampled CW Measurements on Single Crystals of YBa2Cu3O(7-delta) and Bi2Sr2CaCu2O8 |
04 JUN 2001 |
7 pages |
| Authors:
Debashis Dasgupta; WISCONSIN UNIV-MILWAUKEE
|
| Sampled Continuous Wave technique was found most suitable for investigating small single crystals of YBa2Cu3O(7-delta) and Bi2Sr2CaCu2O8. A unique bonding technique has been developed where the sample is pressed on to the transducer with few threads of very thin GE varnish and the transducer is mounted between parallel gold wires and a soft spring to oscillate freely. It has been found that only an optimal coupling between sample and transducer ... |
|
| Investigating Cumulative Damage in a Highly Filled Polymeric Material |
29 MAY 2001 |
14 pages |
| Authors:
C. T. Liu; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE WEST
|
| Objectives: 1) Investigate the effects of strain rate and cyclic loading on cumulative damage in a highly filled polymeric material. 2) Determine the relationship between the NDE damage parameter and material properties. |
|
| Nondestructive Evaluation of Complex Composites Using Advanced Computed Tomography (CT) Imaging |
FEB 2001 |
29 pages |
| Authors:
William H. Green; Patrick Sincebaugh; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| Several methods for nondestructive inspection/nondestructive testing (NDI/NDT) of materials have been known and in use for many years. These methods have included dimensional checks for compliance with specifications, visual inspection for surface defects, various penetrant inspection techniques for small discontinuities that originate at or intersect the surface, and magnetic inspection techniques for small discontinuities that are located at or near the surface. X-ray and various ultrasonic inspection techniques have been ... |
|
| Nondestructive Characterization of Impact Damage in Metallic/Nonmetallic Composites Using X-ray Computed Tomography Imaging |
FEB 2001 |
25 pages |
| Authors:
William H. Green; Joseph M. Wells; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| Characterizing internal impact damage in composites can be difficult, especially in structurally complex composites or those consisting of many materials. Many methods for the nondestructive inspection/nondestructive testing (NDI/NDT) of materials have been known and used for many years, including x-ray film, real-time and digital radiographic techniques, and ultrasonic techniques. However, these techniques are generally not capable of mapping three-dimensional (3-D) complex damage patterns, which is necessary to visualize and understand ... |
|
| Investigating Cumulative Damage in a Highly Filled Polymeric Material |
22 JAN 2001 |
3 pages |
| Authors:
C. T. Liu; AIR FORCE RESEARCH LAB EDWARDS AFB CA
|
| When a highly filled polymeric material consisting of many fine particles is stretched, the sizes and distribution of the filler particles, the crosslinking density of the polymer chains, and the variation of the bond strength between the particles and binder can produce highly nonhomogeneous local stress and strength fields. Because of the particle's high rigidity relative to the binder, the local stress is significantly higher than the applied stress, especially ... |
|
| Nondestructive Evaluation (NDE) Techniques Assessment for Graphite/Epoxy (Gr/Ep) Composite Overwrapped Pressure Vessels |
30 OCT 1998 |
27 pages |
| Authors:
E. C. Johnson; J. P. Nokes; AEROSPACE CORP EL SEGUNDO CA TECHNOLOGY OPERATIONS
|
| NDE methods evaluated included eddy current measurements, ultrasonics, radiography, acoustic emission monitoring, acoustic-ultrasonics, and interferometric (e.g., shearography) methods. The major interest was in the detection of damage to COPVs caused by impacts at energy levels that would leave no visible scar on the COPV surface. Each of the above-mentioned NDE methods was assessed with regards to its utility for the detection of impact damage to COPVs and its applicability in ... |
|
| Technologies for Improving the Evaluation and Repair of Concrete Bridge Decks: Ultrasonic Pulse Echo and Polymer Injection |
SEP 1998 |
283 pages |
| Authors:
Michel Alexander; Richard W. Haskins; Robert Cook; Mantu Baishya; Michael Kelly; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS STRUCTURES LAB
|
| A significant number of concrete bridge decks, both public- and nonpublic use, in the United States are subjected to a variety of detrimental environmental conditions. Many of the decks are in northern regions and are subject to cold weather; some of these are subjected to further degradation from the applications of deicing salts. The current major distress noted is the occurrence of shallow delaminations resulting in ... |
|
| Enhanced Laser Generated Ultrasound |
08 JUL 1998 |
326 pages |
| Authors:
James M. Nelson; Raymond D. Rempt; Stanley M. Sorscher; Wayne E. Woodmansee; William B. Shepherd; BOEING INFORMATION SPACE AND DEFENSE SYSTEMS SEATTLE WA
|
| A Laser Based Ultrasound (LBU) inspection system at McClellan AFB, CA was used to understand actual LBU capabilities and to evaluate its performance versus conventional systems. The effort identified particular classes of aircraft and aerospace parts for which LBU inspection is superior to conventional ultrasonic systems inspection. The evaluation also identified the best procedures for use of the McClellan AFB LBU system and identified shortcomings ... |
|
| Failure Analysis of an 84-MM, M3, Carl Gustav, Recoilless Rifle |
JUL 1998 |
37 pages |
| Authors:
Kevin Miner; Adolf Kapusta; Kenneth Olsen; ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER WATERVLIET NY BENET LABS
|
| During a February 26, 1997 training exercise at Fort Benning, Georgia, an 84-mm, M3, Carl Gustaf, shoulder fired, recoilless rifle; the TACOM- ARDEC Multi-Role, Anti-Armor, Anti-Personnel Weapon System (MAAWS); failed while firing an FFV552 training round. The composite wrapped, steel lined barrel burst open beneath the trigger housing, destroying the weapon but leaving the Gunner and Assistant Gunner uninjured. The rifle (serial number 14051) was evaluated in the ... |
|
| Accuracy of Estimating Compressive Strength of Deteriorated Concrete Seawall by Nondestructive Evaluation (NDE) |
JUL 1998 |
47 pages |
| Authors:
Michel Alexander; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS
|
| A condition evaluation conducted on a concrete seawall using: (a) limited destructive evaluation, and (b) extensive nondestructive evaluation (NDE) measurements demonstrated the effectiveness of the combination method (CM) . The CM was used in conjunction with correlation curves and permitted the estimation of the compressive strength (CS) of the concrete from NDE measurements in locations where no coring was performed. In this study, correlation curves ... |
|
| Selection of a Method for the Measurement of the Protection Factor in the Field (Selectie van een methode voor de meting van de gasmaskerprotectiefactor te velde) |
JUN 1998 |
|
| Authors:
L. A. Steenweg; J. J. van Bokhoven; PRINS MAURITS LABORATORIUM TNO RIJSWIJK(NETHERLANDS)
|
| Until now the protection factors of the FM 12 gas mask have been measured under laboratory conditions; this limits the possibility to simulate the practical circumstances. From the literature it is known that the value of the protection factors, measured under more or less ideal circumstances, are too optimistic. In practice they can be significantly lower. At the request of the DMKL, TNO-PML performed a survey to see if it ... |
|
| Application of Artificial Neural Networks to Ultrasonic Pulse Echo System for Detecting Microcracks in Concrete |
JUN 1998 |
42 pages |
| Authors:
A. Michael Alexander; Richard W. Haskins; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS
|
| Concrete deterioration standards containing various levels of microcracks were engineered by adding calcium sulfate to the concrete mixture and curing under moisture at 38 deg. C (100 deg. F). The level of the mircocracks was classified according to the speed of the ultrasonic pulse velocity (UPV) through the specimens using the American Society for Testing and Material (ASTM) C 597 (ASTM 1994c) test method and was found to vary uniformly ... |
|
| Roller-Compacted Concrete (RCC) Dams; Report 1, Laboratory Characterization of RCC Cores from Elk Creek Dam, Trail, Oregon |
MAY 1998 |
148 pages |
| Authors:
Mark L. Green; Billy D. Neeley; Paul A. Reed; Clayton T. Amundson; ARMY ENGINEER WATERWAYS EXPERIMENT STATION VICKSBURG MS
|
| Ths report documents the results from a laboratory mechanical property investigation of large-diameter, roller-compacted concrete (RCC) core samples obtained from the main Elk Creek Dam, Trail, Oregon. The test matrix included 10 unconfined compression tests, 13 unconfined tension (direct pull) tests, 8 triaxial compression tests, 16 direct shear tests, and 7 splitting tensile strength tests. Eight of the direct shear tests and six of the unconfined tension tests were performed ... |
|
| Monitoring Damage Initiation and Evolution in Filled Polymeric Materials Using Nondestructive Testing Techniques |
APR 1998 |
13 pages |
| Authors:
C. T. Liu; AIR FORCE RESEARCH LAB EDWARDS AFB CA SPACE AND MISSILE PROPULSION DIV
|
| This paper reviews the efforts expanded in evaluation of damage characteristics in highly filled polymeric materials under various loading conditions. Several different nondestructive testing techniques, including ultrasonic, acoustic imaging, and real-time radiography, have been used to monitor damage initiation and evolution processes. The nondestructive testing data were analyzed and the results are discussed. |
|
| Modeling and Simulating Ultrasonic Wave Propagation in Layered Structures |
01 MAR 98 |
62 pages |
| Authors:
J. R. Lhota; AEROSPACE CORP EL SEGUNDO CA TECHNOLOGY OPERATIONS
|
| Launch vehicles and spacecraft have many bonded layered structures, such as the propellant insulation case assembly in solid rocket motors, multilayered printed circuit boards or solar array composite panels in satellites. NonDestructive Evaluation (NDE) techniques are used to ensure bond integrity as part of standard quality assurance programs and/or to restore confidence when an unusual event occurs that may have compromised the hardware. Ultrasonic ... |
|
| Automated Machinery Health Monitoring Using Stress Wave Analysis & Artificial Intelligence |
1998 |
10 pages |
| Authors:
David B. Board; DME CORP FT LAUDERDALE FL
|
| This paper describes the current state of development of a prototype mechanical diagnostic system being developed for the U.S. Army, for application to helicopter drive train components. The system will detect structure borne, high frequency acoustic data, and process it with feature extraction and polynomial network artificial intelligence software. Data for network training and evaluation has been acquired from both healthy and discrepant components, operated over a full range of ... |
|
| Nondestructive Evaluation (NDE) Capabilities Data Book (3rd Edition) (CD-ROM). |
NOV 1997 |
|
| Authors:
NONDESTRUCTIVE TESTING INFORMATION ANALYSIS CENTER AUSTIN TX
|
| File characteristics: Datafile; ASCII and Binary character set. Physical description: 1 CD ROM disc; 650 MB. System requirements: PC compatible; Windows 3.1 or later; MSWord6.0 and EXCEL7.0. This Data Book consolidates and organizes available reference data for demonstrated NDE performance capabilities into a single source. |
|
| Nondestructive Evaluation (NDE) Capabilities Data Book (3rd Edition) |
NOV 1997 |
|
| Authors:
Ward D. Rummel; Georgr A. Matzkanin; NONDESTRUCTIVE TESTING INFORMATION ANALYSIS CENTER AUSTIN TX
|
| This Data Book consolidates and organizes available reference data for demonstrated NDE performance capabilities into a single source. Guidelines are presented for selecting options for use of NDE and for assessing the potential to meet design requirements (critical flaw detection requirements). Guidelines for demonstration of specific NDE process capabilities are also presented. Following a 65 page text (7 chapters) describing various aspects of NDE capabilities quantification, probability of detection (POD), ... |
|
| Ultrasonic Characterization of High Tc and other Unconventional Superconductors |
JUN 97 |
42 pages |
| Authors:
Moises Levy; WISCONSIN UNIV-MILWAUKEE DEPT OF PHYSICS
|
| Ultrasonic techniques were used to characterize the properties of high Tc and other unconventional superconductors. A pontoon technique was developed to investigate thin films with surface acoustic waves SAW. A cw sampling technique was modified in order to sensitively study vortex motion in small superconducting single crystals of YBCO. The penetration field of melt textured YBCO was observed ultrasonically and analysis of the data yields the superconducting energy gap in ... |
|
| Cumulative Damage and Crack Growth in Solid Propellant. Phase I |
FEB 97 |
31 pages |
| Authors:
C. T. Liu; PHILLIPS LAB EDWARDS AFB CA
|
| This report covers results of research addressing the fracture and crack growth behavior of solid propellants in support of structural integrity methodology for the failure response of solid propellant rocket motors. The effects of damage, temperature, and strain rate on local behavior near the crack tip and crack growth behavior in solid propellants were investigated. Numerical modeling techniques were used to determine the local strain fields near the crack tip ... |
|
| Nondestructive Methods for Evaluating Damage Evolution and Material Behavior in Metal Matrix Composites |
FEB 97 |
226 pages |
| Authors:
Prasanna Karpur; DAYTON UNIV OH RESEARCH INST
|
| The overall program consisted of two distinct phases with objectives: Phase I Objective: To characterize the evolution of isothermal fatigue damage using nondestructive evaluation techniques and correlate this information with residual strength of the composite. Phase II Objective: To characterize and compare the evolution of damage due to creep and TMF fatigue of metal matrix composites (SCS-6/TI-6A1-4V manufactured by Textron Specialty Materials) using nondestructive evaluation techniques and thereby derive an ... |
|
| The Evaluation of Thermally Induced Damage in Polymer Matrix Composites via a Design of Experiments Approach |
JAN 97 |
58 pages |
| Authors:
Mark D. Kistner; Ronald J. Kuhbander; Daniel B. McCray; DAYTON UNIV OH RESEARCH INST
|
| As of the date of this report overheat damage is an area of concern for the supportability of polymeric matrix composites, since a significant amount of strength is lost, up to 30% in shear, before this a damage is detectable by standard ultrasonic inspections techniques. This report takes the approach of using a design of experiments to determine which factors and interactions significantly affect the heat damage behavior of polymeric ... |
|
| Acceptance. Phase 5. Acutronic 684-1 Centrifuge |
01 JAN 96 |
8 pages |
| Authors:
Andrew N. Schofield; R. S. Steedman; SCHOFIELD (ANDREW N) AND ASSOCIATES LTD CAMBRIDGE (UNITED KINGDOM)
|
| This report is one of a series of reports by ANS&A Ltd prepared as a part of ANS&A's research under their response to the BAA of December 1988, addressing the completion of the manufacture and assembly stage of the Acutronic 684-1 centrifuge in France during the summer of 1995. The completion of the centrifuge assembly and the Factory Acceptance procedures in France during 1995 was a critical period of intense ... |
|
| Nondestructive Inspection of Piper PA-25 Forward Spar Fuselage Attachment Fitting |
SEP 95 |
24 pages |
| Authors:
David G. Moore; SANDIA NATIONAL LABS ALBUQUERQUE NM AGING AIRCRAFT NDI VALIDATION CENTER
|
| The Federal Aviation Administration's (FAA's) Aging Aircraft NDI validation Center (AANC) at Sandia National Laboratories applied two nondestructive inspection (NDI) techniques to inspect a forward spar fuselage attachment fitting of a Piper PA-25 aircraft. The NDI techniques used were based on radiography and ultrasonic testing methods. Each of these techniques did reveal material thinning in the attachment fitting samples cut from the PA-25 aircraft. Efforts to detect cracks in the ... |
|
| Oblique Ultrasonic Backscatter for Detecting Corrosion at Metal-Rubber Interfaces |
15 AUG 95 |
14 pages |
| Authors:
E. C. Johnson; James R. Lhota; G. C. Panos; J. D. Pollchik; AEROSPACE CORP EL SEGUNDO CA TECHNOLOGY OPERATIONS
|
| An ultrasonic technique for detecting corrosion at metal-rubber interfaces is introduced. The technique, which bears resemblance to the angle beam techniques commonly used in weld inspections, is based on the principle that corrosion pits will backscatter a small percentage of obliquely incident sound. Preliminary data from the study of isolated, artificially induced pits on an aluminum surface are presented. Isolated pits with dimensions on ... |
|
| Loss of High Frequency Upon Propagation through Shock-Damaged Rock, |
14 AUG 1995 |
7 pages |
| Authors:
Thomas J. Ahrens; Cangli Liu; CALIFORNIA INST OF TECH PASADENA SEISMOLOGICAL LAB
|
| The attenuation of stress waves in samples of gabbroic rock subjected to shock loading up to 11 GPa is studied. We determine the attenuation coefficients, alpha sub p, for samples with different damage parameters under dynamic strains of 2 x 10(exp -7) and at frequencies around 2 MHz using the ultrasonic pulse-echo method. A fit to the data yields the P-wave spatial attenuation coefficient versus damage parameter: alpha sub p ... |
|
| The Cyclic Fatigue Behaviour of Adhesive Joints |
12 JUN 95 |
7 pages |
| Authors:
A. J. Kinloch; T. Toh; IMPERIAL COLL OF SCIENCE AND TECHNOLOGY LONDON (UNITED KINGDOM) DEPT OF MECHA NICAL ENGINEERING
|
| In the last six months we have: (a) Concentrated our efforts on the fatigue failure of carbon-fibre PEEK/AFl63 lap joints, and in particular we have started to predict the life time of single-lap joints under cyclic fatigue loading. The analysis is based on data obtained from double cantilever beam (DCB) fracture mechanics tests. (b) Further, we have been successful in measuring the rate of crack growth in lap joints during ... |
|
| Materials for Adaptive Structural Acoustic Control. Volume 4 |
06 APR 95 |
126 pages |
| Authors:
PENNSYLVANIA STATE UNIV UNIVERSITY PARK MATERIALS RESEARCH LAB
|
| The objectives of this ONR sponsored University Research Initiative (URI) entitled "Materials for Adaptive Structural Acoustic Control" concern both basic fundamental studies and highly applied development of the piezoelectric and electrostrictive ferroelectric ceramics which carry both the sensing and actuation functions for adaptive control. The report documents work over the third year of this five year program. For convenience and continuity, the activities are grouped under the headings General Summary ... |
|
Reports by Keyword(s)
ULTRASONIC TESTS
