bluuebunny/crossref_metadata_2025_split huggingface dataset:
Performance of Hybrid Reinforcements in PVC Composites: Part I—Use of Surface-Modified Mica and Wood Pulp as Reinforcements
Authors: Maldas D , Kokta BV 
Published: February 2009

Abstract
In the present study, the hybird behavior of surfacetreated mica and hardwood chemithermomechanical pulp (CTMP) in PVC composites was investigated. In order to improve the compatibility of wood fibers with PVC and surface-coated mica, CTMP was subjected to different surface modifications by pretreating the fibers with maleic anhydride (MA), a mixture of MA and Na-silicate, and with an inocyanate (PMPPIC). The effect exerted by the concentration of reinforcements, composition of hybrid as well as the treatment of CTMP, on the mechanical properties of the hybrid composites were evaluated. In general, these properties improved compared to those of uncoated CTMP/mica-filled composites. Moreover, PMPPIC treatment renked best followed by MA — and MA + silicat treatments. The optimal concentrations of reinforcements and their compositions, which provided superior properties, varied according to the nature of the trestment of CTMP and of the individual mechanical properties themselves.
The Effect of Moisture on Laboratory-Prepared Asphalt Mixtures
Authors: Akili W 
Published: February 2009

Abstract
This paper presents the results of a laboratory study conducted to examine the water-induced damage of compacted and loose asphalt-aggregate mixtures from Riyadh, Saudi Arabia. One asphalt cement and two typical aggregate sources (A and B) were used to prepare asphalt mixtures. Test methods used included the Marshall stability ratio, the wet-dry indirect tensile test (Lottman). and coating and stripping tests of uncompacted mixtures (ASTM D 1664, Test Method for Coating and Stripping of Bitumen-Aggregate Mixtures, and ASTM D 3625. Test Method for Effect of Water on Bituminous-Coated Aggregate-Quick Field Test).
The test results have shown superior performance of mixtures prepared from Source A aggregate in comparison with Source B Differences in physical properties of the fine fraction between the two sources appear to be responsible for the noted difference in behavior However, mixtures with water susceptible aggregate (Source B) have exhibited improved performance when natural sand. used routinely in combination with crushed sand, is reduced or eliminated.
The partial replacement of the crushed limestone filler by cement or lime had positive effects on performance of water-susceptible mixtures. Distinct improvements in 24-h Marshall stability were exhibited when 2% hydrated lime was added.
Based on the results, the test methods deployed in this study appear to do a reasonable job in detecting moisture-susceptible pavement mixtures and in evaluating the relative effectiveness of additives in minimizing water damage potential.
The Effect of Wet Abrasive Wear on the Tensile Properties of Cotton and Polyester-Cotton Fabrics
Authors: Ukponmwan JO 
Published: February 2009

Abstract
The tensile properties of cotton and polyester-cotton woven fabrics have been analyzed in terms of the breaking load, breaking extension, breaking elongation, and elongation at 1 kg (1% full-scale-deflexion (FSD)) using the Instron Tensile Tester, Model 1026. Changes in tensile properties of the woves fabrics as a consequence of wear using the Accelerotor Abrasion Tester in wet conditions are illustrated. The tensile properties before and after abrasion and the effect of abrasion damage on the tensile properties were determined. The Spearman rank correlation coefficient was used to determine the interrelationship between the tensile properties and percentage loss in weight. Relationships between the tensile properties, mass, thickness, density, and specific volume of these fabrics before abrasion are also reported. A significant positive correlation (at 5% and 1% levels) was obtained between breaking load, breaking extension, and breaking elongation, and between breaking extension and breaking elongation in both wet and damp abrasion. Determination of a simple paired t-test showed that there was no significant difference between the unabraded and abraded fabrics (wet and damp), or between wet and damp abraded fabrics at the 95% confidence interval with respect to tensile properties.
Axial-Torsional Fatigue: A Study of Tubular Specimen Thickness Effects
Authors: Bonacuse PJ , Kalluri S 
Published: February 2009

Abstract
A room-temperature experimental program was conducted on AISI type 316 stainless steel to determine the effect of wall thickness on the cyclic deformation behavior and fatigue life of thinwall, tubular, axial-torsional fatigue specimens. The following experimental variables were examined in this study: the depth of the surface work-hardened layer produced in specimen machining, and the effects of strain range and axial-torsional strain phassing. Tubular fatigue specimens were fabricated with wall thicknesses of 1.5, 2.0, and 2.5 mm. One as-fabricated specimen from each wall thickness was sectioned for microstructural examination and microhardness measurement. A specimen of each wall thickness was tested at each of three conditions—high strain range in-phase, low strain range inphase, and low strain range out-of-phase—for a total of nine axialtorsional fatigue experiments. Little or no variation in the fatigue life or deformation behavior as a function of wall thickness was observed. The machining-induced work-hardened zone, as a percentage of the gage section material, was found to have a minimal effect on both deformation behavior and fatigue life. Out-of-phase fatigue tests displayed shorter fatigue lives and more cyclic hardening than in-phase tests.
Effects of Wash Temperature on Bacterial Survival and Strength Retention of Cotton Fabrics
Authors: Perenich TA , Moore MA 
Published: February 2009

Abstract
The influence of temperature, detergent type, and labric finish on bacterial survival and strength retention and clongation in fabrics were investigated in this study. Previous research has shown that temperature is a critical factor in the removal, redeposition, and destruction of microorganisms in the laundering process. The results showed that fabric finish did not have any significant effect on bacterial survival but did influence both strength retention and breaking clongation. Temperature significantly affected bacterial survival and breaking strength and clongation. The addition of a detergent, especially a phosphate detergent, in the laundering process is important in diminishing bacterial survival on fabrics.
Embrittlement of an AISI 8640 Lower Bainite Steel
Authors: Rinnovatore JV , Lukens KF , Reinhold J , Mahon W 
Published: February 2009

AbstractA study was performed to determine the cause of an abnormally low fracture toughness of an AISI 8640 resulfurized steel. The embrittlement effects of phosphorus and arsenic on this steel heat-treated to a lower bainitic structure were studied by employing fracture toughness tests, Charpy impact tests, X-ray fluorescent spectroscopy, and scanning electron microscopy (SEM). The results showed that the steel was embrittled by phosphorus at prior austenite gram boundaries in a manner similar to the tempered martensite embrittlement (TME) phenomenon. Arsenic is also believed to be involved in the embrittlement effect, specifically as related to producing a reduction in the upper shelf Charpy impact energy. Embrittlement was manifested by a reduced fracture toughness, an increase in the Charpy transition temperature, and intergranular fracture.
Influence of Substrate Deformations on the Thermal Fatigue Life of SMT Solder Joints
Authors: Zafran JB , Sandor BI 
Published: February 2009

Abstract
Previously published expressions based on life data for bulk solder are used in this paper to calculate the number of thermal cycles to failure of the solder joints of leadless chip carriers attached to various substrates. The devices used by Hall in thermal chamber cycling and power cycling are chosen for analysis. The values of deformations in terms of shear strain range and total mismatch are presented and compared. The fatigue lives of the solder joints are predicted based on the deformation data, the test conditions, and the Coffin-Manson expression. Attempts are made to correct some crucial differences in previous work or to fill in for missing information. The resulting predictions are explained according to the specific models used.
Mean Stress Diagrams for Composites Generated Using a Modified Up-and-Down Test Methodology: Part II—Limited Preliminary Data
Authors: Little RE 
Published: February 2009

Abstract
Constant-stress-amplitude axial-load fatigue tests were conducted to generate mean stress data for notched and unnotched specimens of a compression molded thermoset composite material with 27% (by weight) randomly oriented 1.0-in.- (25.4-mm) long E-glass fibers in a (Phase Alpha) polyester matrix. Maximum likelihood point and interval estimates for median fatigue strengths at 107 cycles were computed for four stress ratios R (−1.0, −0.2, +0.2, and +0.6) based on tests conducted following a modified small sample up-and-down methodology appropriate when limited preliminary data are available to aid in test planning.
Characterization of Defects in Graphite Fiber Based Composite Structures Using the Acoustic Impact Technique (AIT)
Authors: Raju PK , Patel JR , Vaidya UK 
Published: February 2009

Abstract
Acoustic Impact Technique (AIT), commonly known as “coin-tapping,” has been applied by previous investigators as a nondestructive evaluation technique to study disbonds in composite honeycomb structures. The experimental configuration adopted by previous investigators was somewhat restricted. In this study, a different approach to AIT is developed. This was done to overcome the experimental constraints encountered in the previous approaches. This paper presents experimental results obtained in the evaluation of defects commonly found in graphite based composite structures, such as delamination, fiber breakage, and misaligned fibers. The experimental approach adopted in this work has two main features. Primarily, the force-time history of the specimen's response to a low magnitude input pulse in different regions of the specimen is compared. Secondly, an Acoustic Emission (AE) wide band sensor was used in conjunction with the conventional acoustic impact technique. The combination of the AE sensor and AIT enabled the study of the material interaction with stress waves generated in the vicinity of the tapped region. Gross defects such as delaminations were identified through the change in the pulse width of the force input, while defects such as fiber breakage and misaligned fibers were successfully identified using AIT in conjunction with AE.
Characterization of Hypervelocity Impact Debris: Naval Research Laboratory Tests
Authors: Fortson BH , Winter JE 
Published: February 2009

Abstract
Characterization of debris from hypervelocity impact events is an important prerequisite for analytical or empirical predictive modeling of those events. One feature of a useful model would be its ability to predict the characteristics of the debris cloud produced by the impact, and this feature cannot be evaluated without a body of test data with which to compare the analytical predictions. In the current effort, debris produced by hypervelocity impact experiments at the Naval Research Laboratory (NRL) is collected and described. An attempt is also made to construct a parametric model of the data in order to assess the effectiveness of this approach. A model based on a linear relationship is seen to perform well, while a parabolic relationship performs less well, and a bilinear relationship performs poorly. A lognormal distribution is seen to describe the debris more effectively them an exponential distribution. However, the performance of the exponential distribution is seen to improve when the very largest fragments are removed from consideration.
Maximum-Load Predictions in the Dugdale Model Using a Critical CTOA Criterion
Authors: Gu I 
Published: February 2009

Abstract
An engineering method of elastic-plastic fracture analysis is suggested for plane-strain specimens under tension. The condition for an increment of crack extension is set by a critical increment of crakc tip opening displacement (CTOD). The CTOD increment divided by the incremental crack extension is a critical crack tip opening angle (CTOA), assumed to be constant for a material of a given thickness, characterizing the tearing resistance of material. Based on a finite-element analysis of crack tip deformation, a load term in the CTOD equation of the Dugdale strip yield model is modified to accommodate large and small scale yielding, for which cohesive stress in the strip is assumed greater than that for the plane-stress model Approximate generalization of the Dugdale model is suggested for finite-size specimens. A definition of CTOD is reviewed with a round and sharp crack tip. In a successive application of the CTOA criterion at a current extending crack tip, the integration of the incremental crack extensions and load increments after fracture mitration gives a relationship in which a maximum load is either a peak load or a limit load on an unbroken ligament. Material constants are evaluated so that the calculated loads agree with test loads at each crack extension. The proposed method is applied to various specimens of 304 stainless steel for which test data are available.
Laboratory Testing Procedure for Evaluation of Moving Bed Catalyst Attribution
Authors: Doolin PK , Gainer DM , Hoffman JF 
Published: February 2009

Abstract
A laboratory scale attribution test has been designed to simulate particle-particle and particle-wall attrition forces which are similar to those experienced in commercial moving bed units. The modified drum test uses two concentric rotating drums to induce particle breakage. Using this test, the distribution of particle shapes and sizes produced by catalyst attrition in a moving bed unit have been successfully duplicated.
What's New in Traceability
Authors: Garner EL , Rasberry SD 
Published: February 2009

Abstract
The traditional concept of measurement traceability in the United States has focussed on an unbroken hierarchial pathway of measurement compatisons to national standards Also ingrained in tradition is the tendency to focus on the audit trail rather than on a quality measurement assurance program in which there is sufficient accuracy to accomplish the intended purpose. Evolutionary changes in the U.S. concept of traceability and the forces producing them will be reviewed. Specific examples are used to illustrate the traditional approach to traceability as well as options that might be exercised in the future.
Pressure and Flexible Membrane Effects on Direct-Contact Extensometer Measurements in Axisymmetric Compression Tests
Authors: Mellegard KD , Pfeifle TW , Fossum AF , Senseny PE 
Published: February 2009

Abstract
Axisymmetric compression tests have become routine tests in laboratory experiments on pressure-seasitive materials like geologic material. The usual compression test unes right-circular-cylindrical specimens that are encased in a protective membrane, placed in a pressure vessel, and then subjected to some combination of axial stresses and confining pressures. The best measurement of the resulting specimen deformation can be made by installing pressure-rated instrumentation directly on the specimen. However, responsible experimental practice requires that the effects of pressure and the protective membrane on the deformation measurements be understood. This paper attempts to quantify such effects.
The investigation began with an evaluation of the pressure effects on the instrumentation. Significant pressure effects required that correction factors be introduced. After these pressure effects had been quantified, four types of protective-membrane conditions were tested in three common types of compression tests. The four conditions were: (1) no jacket, (2) thin jacket, (3) thick jacket, and (4) ported jacket. The three compression tests included hydrostatic compression (HC), triaxial compression (TC), and uniaxial strain (US). A single result at each combination of jacket condition and test mode required that twelve tests be performed. The results show that protective membranes can have a very significant effect on the elastic moduli calculated from the deformation measurements, but in some cases the errors can be reduced or eliminated through the use of correction factors or specially designed membranes.
A Comparison of Calculated Geometric Surface Area and Measured BET Surface Area for a Metal Powder
Authors: Schrøder-Pedersen A , Kjøller J , Larsen B 
Published: February 2009

Abstract
The specific surface areas of gas atomized (spherical) metal powder fractionated into 6 size fractions below 125 μm were determined by BET measurements and by geometric derivation from particle size distributions. The areas obtained were compared and a linear correlation was found. Even though the total areas measured were relatively low, in the range of 0.3 m2, the BET measurements followed the areas derived from particle size with a proportionality factor around 1.8. It was concluded that BET surface area measurements represent true area closely, when true area is understood as the envelope best fitting the powder particles. The deviation of the BET measurements from the true area is concluded to be less than 20%, with increasing accuracy for increasing specific surface area.
New Technique for Evaluating Damping of Longitudinal Free Vibration in Wood-Based Materials
Authors: Cai Z , Hunt MO , Fridley KJ , Rosowsky DV 
Published: February 2009

Abstract
Classical log-decrement techniques have been used to evaluate the damping property of materials. However, the consistency and repeatability of the methods when applied to wood and wood-based materials have been found lacking. A different way to view the free vibration of a single-degree-of-freedom system in the x − ˚x plane is presented. A new method that uses all sample points and does not require a knowledge of the initial conditions to determine the damping properties is developed. A comparison between the new method and the classical method is made for three wood-based materials: solid wood, medium density fiberboard (MDF), and particleboard. The results show that the new method is more consistent and repeatable in measuring damping than the classical method. For the six cases examined, there was an absolute average difference of 3.8% in measuring log-decrement between the methods.
Crack Tip Opening Displacement (CTOD) Toughness Evaluation by ASTM E 1290 and BS5762: A Comparative Analysis
Authors: Bhattacharya S , Kumar AN 
Published: February 2009

Abstract
ASTM Committee E-24 on Fracture has recently standardized the crack tip opening displacement (CTOD) measurement method. Three major differences between the ASTM E 1290-89 method and British Standard BS5762:1979 are outlined, and the influence of these differences on the critical crack initiation CTOD value is studied. The study is based on a typical fatigue crack and slow crack growth front profile. A difference of up to 6% in the CTOD values between the two standards, irrespective of the slow crack growth size, was found in the present study. However, a marginal ditterence of only 2% in the initiation CTOD value could be observed for the slow crack growth situation considered.
Critical Assessment of Methods for JIc Determination
Authors: Pandey RK , Sundaram P , Kumar AN 
Published: February 2009

Abstract
Various methods for the evaluation of J-initiation toughness have been compared by conducting investigations on Mo and Cr-Mo steel at different temperatures (i.e., 30 to 460°C) by employing the single-edge-notch bending configuration. The methods investigated include ASTM Standard E 813, a method proposed by the European Group on Fracture (EGF), methods based on a stretch zone approach, and a proposed method of the Japan Society of Mechanical Engineers (JSME). The blunting line approach for toughness determination has been investigated in detail in the light of various propositions made by other investigators, and an equation for the blunting line has been proposed based on the findings from the present work as well as from literature data. A J-resistance curve based on mid-thickness crack growth combined with the stretch zone approach for the blunting line appears to provide a mose comsistent method for toughness determination.
Tensile Stress Relaxation in High-Strength Spring Steel Wire
Authors: Sinha UP , Levinson DW 
Published: February 2009

Abstract
Stress relaxation data were obtained in tension tests using the vibrating string technique (measuring the resonance frequency) in spring steel wire of ASTM Grade A 228 (also known as music wire). The steel wire of 0.56 mm diameter had a 0.29% offset tensile yield strength of 1689 MPa. Tests were conducted at low temperatures in the range of 23 to 140°C, and at initial stress levels of up to 75% of the 0.20% offset yield strength of the wire. The test duration was to 4000 h at 23°C and to 100 h at temperatures to 140°C. The test results indicate a faster rate of stress relaxation during the early stage of stress relaxation, and subsequently a slower rate of stress relaxation rate with increasing time, as is usually observed. An empirical equation has been determined that fits the experimental data very well under the given test conditions.
Accelerated Weathering of Marine Fabrics
Authors: Mooce MA , Epps HH 
Published: February 2009

Abstract
Fabrics designed to be used in marine applications must retain strength and resist color change over prolonged exposure to a variety of potentially degrading factors, including sunlight, variations in temperature and relative humidity, and repeated cycles of wetness and dryness. This research focused on the effects of instrumental weathering on the end-use performance properties of three woven marine fabrics currently available for use as sails. The fabrics were 100% polyester, 100% acrylic, and 100% nylon. Changes in fabric color and tensile properties were analyzed after exposure to three levels of simulated sunlight under both dry and moist conditions.
Fracture Toughness Determination Related to Indentation Problems Avoidance in Three-Point Bend Specimens
Authors: Santarelli EL , Perez Ipiña JE 
Published: February 2009

Abstract
In elastic-plastic fracture toughness of the three-point bend specimens (3P-SENB) test, fracture toughness is obtained as a function of the energy put into the specimen, and it is measured from the area under the load versus load-line displacement record. A fraction of this energy is not developed as a work in the crack tip, but it is expended in plastic deformation near the loading points. There also exists an overestimation of this energy because of spurious displacements involved between measurement points when a remote transducer is used to measure the load-line displacement. Actual standards provide some techniques to discriminate this spurious energy from the total measured energy.
By checking the experimental setup performance, some differences are evident between the proposed corrections and the real phenomenon during the test. In this paper a simple method for measuring the load-line displacement is proposed, which is able to avoid automatically the spurious energy.
The energy developed by the load components on the outer loading points and its contribution on J is also discussed, and equations to take into account this energy are proposed.