bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of Pneumatically Driven Staples in the Practice of Orthopaedic Surgery
Authors: Shapiro JS , Walt MJ 
Published: February 2009

Abstract
In 1981, the concept was delineated of driving staples “in a guided fashion with a rapid and reproducible power source” for fixation in orthopaedic surgery. This transformed an inefficient fixator into an efficient one and secondarily allowed its use in many unique applications for fixation of bone to bone, ligament to bone, and cartilage to bone. From first clinical usage in 1983, it has been used in an estimated 40 000 cases worldwide. Fixation has been for solitary, supplemental, and/or temperary applications in metaphyseal bone for such diverse applications as fusions, osteotomies, fractures, and ligament attachment. The system has been tested and improvements in fixation were demonstrated in laboratory and in vitro studies. The rectangular, rough surfaced, titanium staples were designed for pneumatic insertion to bone and have found use in specific applications as well as a ubiquitous backtable instrument. A learning curve exists for proper usage.
Fracture Testing Wood Adhesives with Composite Cantilever Beams
Authors: Scott CT , River BH , Koutsky JA 
Published: February 2009

Abstract
A new approach to evaluating wood-adhesive joints is being used by the Wood Adhesives Science and Technology Research Work Unit at the Forest Products Laboratory. This test involves the measurement of adhesive fracture toughness in Mode I cleavage. It is an extension of the contoured double cantilever beam (CDCB) test developed by Mostovoy and others [1] and generally follows the procedures outlined in ASTM D 3433 [2]. Samples are prepared by bonding thin wood laminates to contoured aluminum beams. The addition of a laminate to the aluminum adherends significantly reduces the change in linear compliance with crack surface area (dC/da) of the composite, thereby influencing the calculation of fracture toughness. This effect is established both experimentally and theoretically.
High Temperature Tube Burst Test Apparatus
Authors: Shelleman DL , Jadaan OM , Butt DP , Tressler RE , Hellmann JR , Mecholsky JJ 
Published: February 2009

Abstract
The design and construction of a high temperature tube burst test apparatus is described. The apparatus consists of an internally heated ceramic tube specimen, internal O-ring pressure seals, water-cooled end caps, steel end plates, and an explosion-resistant steel test chamber. The ceramic tube specimen floats freely on the internal O-ring seal, thus avoiding axial stresses due to end constraints and/or axial thermal expansion. The apparatus is capable of obtaining test temperatures up to 1400°C, pressures to 68.9 MPa (10 000 psi), and capturing tube fragments in a “witness shield” for fractographic analysis. The use of the apparatus is demonstrated by relating strengths measured for 660 mm (26 in.) long by 44 mm (1.75 in.) diameter SiC tubes to the strength distribution of O-ring and C-ring specimens tested at 1200°C using Weibull statistics to scale the specimen sizes. Advantages and disadvantages of the tube burst test apparatus are discussed.
An Evaluation of Strain Measuring Devices for Ceramic Composites
Authors: Gyekenyesi JZ , Bartolotta PA 
Published: February 2009

Abstract
A series of tensile tests were conducted on SiC RBSN composites using different methods of strain measurement. The tests were used to find the optimum strain sensing device for use with continuous fiber reinforced ceramic matrix composites in ambient and high temperature environments. Bonded resistance strain gages were found to offer excellent performance for room temperature tests. The clip-on gage offers the same performance but significantly less time is required for mounting it to the specimen. Low contact force extensometers track the strain with acceptable results at high specimen temperatures. Silicon carbide rods with knife edges are preferred. The edges must be kept sharp. The strain measuring devices should be mounted on the flat side of the specimen. This is in contrast to mounting on the rough thickness side.
Compression of Single-Wall Corrugated Shipping Containers Using Fixed and Floating Test Platens
Authors: Singh SP , Burgess G , Langlois M 
Published: February 2009

Abstract
The compression strengths of five different RSC style corrugated fiberboard containers were obtained using both fised and floating compression test platens in order to determine the effect of the platen on the results. The difference between the compression strength using fixed and floating platen methods was found to be small compared to the normal variation in compression strength between identical boxes. It is concluded that either test method is suitable.
Young's Modulus of a Dispersion Strengthened Al-Fe-V-Si Alloy
Authors: Srinivasan MN , Wolfenden A , Little S , Sridhara S 
Published: February 2009

Abstract
Young's modulus for a dispersion strengthened Al-Fe-V-Si (FVS 1212) alloy has been measured using PUCOT (Piezoelectric Ultrasonic Composite Oscillator Technique), after melt spinning the alloy under different combinations of nozzle size, wheel speed and power input. It is found that the interactions among the three variables exert a strong influence of the Young's modulus. Young's modulus measurements using PUCOT were also made on melt spun ribbons of three other aluminum alloys. Electron diffraction patterns of the ribbon specimens suggest that crystalline structures lead to promote higher modulus in all the aluminum alloys examined.
Monitoring Fatigue Crack Propagation in Compact Tension Specimens via Remote Sensing of Back Face Strain
Authors: Simha KRY , Hande HSS , Arora PR 
Published: February 2009

Abstract
Back face strain (BFS) measurement is now well-established as an indirect technique to monitor crack length in compact tension (CT) fracture specimens [1,2]. Previous work [2] developed empirical relations between fatigue crack propagation (FCP) parameters. BFS, and number of cycles for CT specimens subjected to constant amplitude fatigue loading. These predictions are experimentally validated in terms of the variations of mean values of BFS and load as a function of crack length. Another issue raised by this study concerns the validity of assigning fixed values for the Paris parameters C and n to describe FCP in realistic materials.
Calculation for Rolling Contact Fatigue Life and Strength of Case-Hardened Gear Materials by Computer
Authors: Jiang B , Zheng X , Wang M 
Published: February 2009

Abstract
An analysis of the rolling contact tatigue process of case-hardened gear material by means of clasticity and fracture mechanics theory has been made: the stress intensity range Δk and equation for crack growth da/dN = c(Δk)″ was put forward to calculate their fatigue life and strength in this work. The results show that the calculated data are in good agreement with the experimental ones for compound-treated, sprayed, and carbonitrided specimens. The relative errors of logarithm of cycle number are all less than 5′
Up-and-Down Methodology Applied to Statistically Planned Experiments
Authors: Little RE , Thomas JJ 
Published: February 2009

Abstract
Twenty-four modified small sample up-and-down tests were conducted to estimate the median endurance limits of unplated and cadmium-plated ½-13NC 2A machine screws of SAE Grades 2, 5, and 8, each fastened using standard geometry SAE Grade 2 zincplated nuts or Ranged SAE Grade 8 nuts (termed toolmarker's nuts). The test program was a split-plot experimental design with six mainplots (three grades of machine screws, each unplated or cadmium-plated) and two split-plots (nut-type) within each main-plot. This test program was repeated to form two time-blocks, each time-block involving twelve modified small sample up-and-down fatigue test sequences conducted under test conditions that were as uniform as practical. Based on prior test data, the effect of the split-plot factor, nut-type, was of primary interest in this study. Two statistical analyses are discussed herein: the standard (parametrie), analysis of variance and an alternative nonparametric analysis. Recommendations are made on how to conduct similar multifactor test programs involving up-and-down test sequences to estimate the median endurance limits of interest.
More Rapid Edgewise Crush Test Methods
Authors: Urbanik TJ , Catlin AH , Friedman DR , Lund RC 
Published: February 2009

Abstract
The use of paraffin wax to reinforce the loading edges of corrugated fiberboard edge-crush specimens requires that the specimens be reconditioned after waxing. The traditional practice employing a 24-h reconditioning period is a conservative approach based on the moisture response rate of corrugated containers. An interlaboratory study was conducted to determine the effect of reconditioning time on edgewise compressive strength of waxed specimen prepared by standard test methods. Results showed that reconditioning time can be reduced from 24 h to 2 h wish no significant change in test values. The results apply to flexible-beam and rigidplaten loading machines, but at conventional loading speeds, the flexible-beam machine yielded higher overall streagth values. Other tests were conducted to evaluate the performance of an edge-clamping fixture for use with unwaxed specimens. When tested with heavy basis weight materials, the fixture did not yield equivalent results compared to those obtained with lighter grade waxed apecimens.
Asbestos-Free Gasket Materials for Turbines
Authors: Jones WF , Seth BB 
Published: February 2009

Abstract
The results of a systematic program undertaken to evaluate potential substitute materials for asbestoe-free gaskets used in power plant turbines are reviewed. Thirty-three commercially available materials were subjected to a series of tests reflecting the requirements of a good gasket material for turbine applications. The results identified flexible graphite as the only material to meet or exceed the properties of asbestos gaskets. One limitation of flexible graphite uncovered in the program, however, is its relatively high stress relaxation behavior especially at temperatures above 650°F (343°C). Ten-thousand-hour stress relaxation tests were conducted in the temperature range of 500 to 850°F (260 to 454°C) to determine the usable temperature limit of flexible graphite. The effects of joint flexibility and reloading were also evaluated at high temperatures.
Fatigue and Corrosion Fatigue of Beryllium-Copper Spring Materials
Authors: Bagheri R , Miller GA 
Published: February 2009

Abstract
Fine gage, 0.006-in. (0.15-mm) thick, beryllium-copper (Be-Cu) spring materials with tensile strength in the range of 70 to 145 ksi (482 to 999 MPa) were subjected to cyclic loading in air and salt water environments. Plain and notched (center hole) “hour glass” specimens were subjected to sinusoidal loading with R = (minimum maximum) stress = 0.1 at cyclic frequencies of 50 Hz in air and 1 Hz in salt water. Fatigue life was typically from 104 to 106 cycles with crack initiation as the dominant fatigue process.
The excellence fatigue performance of Be-Cu alloys in salt water is well-known, however, current findings demonstrate 10 to 37% reduction in fatigue strength of unnotched specimens in this environment for a life of 3 × 105 cycles. This strength degradation is attributed to the use of a lower cyclic frequency for present than for previous tests, i.e., 1 versus about 20 Hz. There was no effect of salt water on crack initiation in notched specimens.
The ratios of the fatigue strengths, namely (cold-rolled annealed) and (aged/annealed), for plain and notched specimens tested in air, decreased from 2 to about 1.4 as fatigue life increased from 104 to 106 cycles. This effect is attributed to cyclic hardening of the annealed material. The fatigue stress concentration factor, Kt = (plain notched) fatigue strength, increased by about 30% as fatigue cycles increased from 104 to 106. The ranking of Kf values of the various material conditions from highest to lowest was: cold-rolled, aged, and annealed.
Minimization and Quantification of Error Associated with theKGradient and the Interval of Crack Length Measurement in Fatigue Crack Growth Testing
Authors: Oore M 
Published: February 2009

AbstractAnalytical method has been developed to minimize and quantify the effect of crack length measurement interval Δa on the error due to the K gradient in the interpretation of da dN derived from crack growth test data using the secant method. The associated error has been quantified in a general form and used to demonstrate the specific errors due to the selection of average crack length a per ASTM E 647-91. Test Method for Measurements of Fatigue Crack Growth Rates. It is shown that the selection of the geometric mean (a¯=a1a2) in the data analysis will reduce the associated error in the crack growth rate interpretation. It is recommended that ASTM E 647-91 be revised accordingly.
Effect of Internal Gas Pressure on the Compression Strength of Beverage Cans and Plastic Bottles
Authors: Singh SP , Burgess G 
Published: February 2009

Abstract
This study investigated the compression strength of various sized polyethylene terephthalate (PET) bottles and steel and aluminum two-piece cans. Compression tests were performed on both empty and filled containers under pressure. A stress analysis is developed to provide a simple prediction formula. The predictions are shown to be in fair agreement with actual values obtained from the compression tests. The results show that internal pressure can increase the compression strength of a beverage package by as much as three times. Erratum to this paper appears in 21(4).
The Gel Electrode Revisited: Fatigue Crack Detection with a Polymer Film
Authors: Baxter WJ 
Published: February 2009

Abstract
The gel electrode provides a very seasitive technique for detecting and imaging fatigue cracks in metals. In the past, its utility has been restricted by the requirement that, prior to the formation of a crack, the metal surface must be associated to form a thin insulating film. This film is ruptured as a crack forms, so that an impressed current from a gel electrode flows preferentially to the crack and forms an image. In this study, the anodic film has been replaced by a cathodically deposited polymer film. This film is much easier to apply, is applicable to any metal, and can be applied either before or after crack formation. If applied prior to fatigue loading. it is ruptured in the same manner as an anodic film, but it provides much better insulation, so that freshly formed cracks can now be detected in materials such as cast irons. If applied after fatigue loading, the film does not cover up the previously formed cracks so that the gel electrode current still flows preferentially to the crack. Both sequences of application are illustrated by images of fatigue cracks in low-carbon steel, nodular iron, and austempered ductile iron. The only difficulty experienced has been with previously formed cracks held tightly closed by retained compressive stresses. Otherwise, this combination of a polymer film and the gel electrode will detect cracks as small as 0.3 mm in length.
Infrared Technique as a Research Tool for Measuring Water Vapor Transmission of Roofing Membranes
Authors: Dutt O , Lavallée C , Ashton HE 
Published: February 2009

Abstract
Measurements of the permeability to water vapor of materials intended to prevent its transmission are time-consuming with the usual cup method [1]. Several instruments have been promoted as being capable of providing results rapidly, but doubts about their agreement with cup measurements have delaved their use for more than quality control.
One instrument with an infrared sensor was studied to investigate its accuracy and to correlate results obtained with the standard cup methods. Factors studied include those that contribute to the inconsistent performance of the instrument, especially for research work Techniques for improving the precision and the accuracy of the instrument are discussed. The permeances of roofing papers and telts and of plastic films by both the modified IR instrument and the cup methods are reported and compared to values given in the literature.
A Detection Method of Fatigue Crack Initiation by Analyzing Strain Waveform
Authors: Makabe C , Nishida S , Kaneshiro H 
Published: February 2009

Abstract
A detection method of fatigue crack initiation at some weak section of machine equipment during operation is examined using a partial-notched specimen. The waveform of the strain function composed of strains in the vicinity of the partial notch was observed successionally. It is found that such strain waveform changes its figure at the time when the crack length is 1 mm, due to the crack closure behavior. Therefore, in this experiment, the crack initiation could be detected when the crack length is about 1 mm. Since the engineering crack initiation size is frequently taken to be 1 mm, the present method of detecting crack initiation can be applied to real machine equipment. Also, this waveform was analyzed with FFT (Fast Fourier Transformation). Power spectrum density of the waveform varies immediately after the crack length reaches 1 mm. Furthermore, the figure of the coherence of two waveforms composed of the same strains clearly varies at the same crack length of 1 mm. Thus, it is thought that the engineering size crack initiation can be detected by the analysis of the strain waveform.
Some Microstructural Conditions for Evaluating Fracture Toughness and R-Curve Behavior in Platelet-Reinforced Composites
Authors: Pezzotti G , Niihara K , Nishida T 
Published: February 2009

Abstract
The validity of Kk determinations by various techniques usually employed and compared with each other is discussed in detail for two ceramic materials. They are a simple Si9N4 material fracturing with transgranular crack propagation and a Si9N4-25vol% SiC-platelet measured by four different methods: single-edge V-notched beam (SEVNB), single-edge precracked beam (SEPS), indentation fracture (IF), and chevron-notched beam (CNB). It is generally recognized that, in platelet composites, Kk values can be reliability obtained only by procedures adopting notched specimens in which the wake-zone of precracking is mechanically removed (SEVNB or renotched SEPB). In the present investigation the CNB method, in which the wake contribution to fracture resistance is generally small but not negligible, was also found to give stress-intensity factors at maximum load whose value was almost coincident with the KIc determined by SEVNB method. Using stereological concepts, fractographic observations, and acoustic emission (AE) experiments, the microstructural conditions for negligible wake-contribution during the subcritical stable crack extension in the CNB experiment were worked out and applied to rationalize the behavior of the present composite. Apparent toughness values markedly higher than the “true” Kk of the composite were measured both by the standard SEPB and IF method. Such a discrepancy is considered due, in the former case, mainly to traction forces between the precracked surfaces while, in the latter, to an insufficient account of the residual stress field associated with the indentation.
Metallized Microballoon Filled Composite EMI Shielding Materials
Authors: Radford DW , Cheng BC 
Published: February 2009

Abstract
The need for lightweight, formable materials that can conduct elasticity and shield against electromagnetic interference (EMI) is widespread. Applications ranging from modeled cases for terrestrial electronics to shielding systems for metallize can benefit from such tailorable, lightweight conductive materials. This paper explores the possibility of creating a new family of ultra-lightweight conductive shield materials using metallized microballoons as a conductive filler material. The conductive costings investigated include gold, silver, and aluminum on ceramic microballoons in an epoxy matrix. Factors influencing the electrical conductivity are discussed, and the shielding performance is tested using X-band microwave transmission measurements and anechoic shielding effectiveness testing. Variables available that have the potential to allow application specific tailoring of the shielding material are described. Initial findings are discussed and performance is related to the microballoon volume fraction and costing materials. Results indicate that shield densities significantly below 1.0 g/cm2 are possible, with electrical surface resistivities approaching these of common metals.
Lifetime Predictions of uPVC Pipes from Short Time Tests
Authors: Seldén R , Gradin PA 
Published: February 2009

Abstract
Fracture mechanics tests according to British Standard 3505 have been made on two unplasticized polyvinyl chloride (uPVC) pressure pipes. The applied load was varied and time to failure was measured as a function of load. The results were fitted to an empirical power law, using the concepts of linear elastic fracture mechanics, relating crack growth rate, v, to the stress intensity factor, K1, according to v = A K∞1, where , where A and α are α constants. The parameters A and α were then applied to uPVC pipes provided with assumed Flaws of different sizes and shapes, and lifetime was calculated as a function of internal pressure.
Close agreement with published ductile failure data of uPVC pipes were obtained for elongated, axial flaws on the inside wall, between 0.8 and 1.0 mm in size.
Compaction of Asphalt Mixtures for Laboratory Testing: Evaluation Based on Density Profile
Authors: Fwa TF , Low BH , Tan SA 
Published: February 2009

Abstract
Cylindrical specimens are commonly used in laboratory testing of asphaltic paving mixtures. This paper describes a study that examined the influence of different compaction methods on the resulted density distributions of cylindrical specimens using a laboratory twin-probe nuclear density gage. Two common sizes of 102 mm (4 in.) cylindrical specimens, namely 64-mm (2.5-in.) high Marshall-size specimens, and 200-mm (7.87-in.) high triaxial test specimens, were considered in the test program. Four compaction methods were studied: drop-hammer compaction, kneading compactions, single-plunger compression, and double-plunger compression. In the case of 200-mm-tall specimens, the effect of compaction in layers was also examined. Test results show that, except for the kneading compaction method, the other three methods could all produce 64-mm-tall Marshall-size specimens of relatively uniform density distributions with density variation within 0.05 g/cm3. For 200-mm-tall specimens, only the double-plunger compression method was able to produce specimens with density distribution of similar uniformity.
A Fiber Optic Chemical Sensor for Measurement of Groundwater pH
Authors: Maher MH , Shahriari MR 
Published: February 2009

Abstract
A fiber optic chemical sensor was developed for measurement of pH in groundwater. The sensor consists of a porous polymeric film immobilized with pH indicator, housed in a porous probe. The optical spectral characteristics of the sensor showed very good sensitivity to changes in the pH levels tested when visible light (380 to 780 nm) was used. The sensor/probe system was tested in a laboratory environmental chamber and showed very-good stability and reversibility under various confining pressures and flow rates.
Dynamic Testing of the Strength of Helmet Chin Straps
Authors: Gilchrist A , Mills NJ 
Published: February 2009

Abstract
A dynamic test of-chin strap strength was introduced into the British Standard BS 2495 in 1980. This test has subsequently been adapted for bicycle and horse riding helmets without the same correlation between accident and test failures being established. The causes of force peaks and oscillations in the test traces have been identified, and a means was found of obtaining reliable chin strap force measurements. Recommendations are made for improving the test so that chain straps and buckles are adequately strong but not over-designed.