bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterizing Shock Absorbers for Ground Vehicle Simulation
Authors: Whelan AE
Published: February 2009

A new method of ground vehicle shock absorber characterization using lumped acceleration excitation is presented. By using a triangular waveform and lumping the acceleration at the beginning and end of travel, this method produces a 27% larger mapping on the phase plane than traditional harmonic (sinusoidal waveform) excitation characterization. Force response surfaces are created based on the lumped acceleration and on harmonic excitation data. A difference surface is created between the common regions of both force response surfaces. A correlation is made between the response of the lumped acceleration force response surface to harmonic inputs and observed data. Hysteresis effects are noted using the lumped acceleration force response surface at low frequencies. A standard materials testing machine is used to characterize the shock absorber.
Microcracks: The Hazard Function and Reliability Inspection
Authors: Lawson L , Chen EY
Published: February 2009

Reliability inspections of structures for fatigue cracks are traditionally conducted at equispaced intervals because, it is assumed, the average slope of the hazard function following an inspection does not change from one inspection to the next. This study examines the common case where fatigue cracks nucleate continually over time. In such cases it is found that the slope of the hazard function after inspection may tend to increase from one inspection to the next, suggesting that inspection intervals should decrease with increasing service life. A formalism is introduced that allows calculation of the hazard function from microcrack data.
Fractographic Examination in the Scanning Electron Microscope as a Tool in Evaluating Through-Thickness Tension Test Results
Authors: McDonald MM , Ludwigson DC
Published: February 2009

The through-thickness tension test is used to assess resistance to lamellar tearing. Observed through-thickness reduction-of-area (TTRA) values are usually well above the 20% minimum specification level in steels produced for lamellar-tearing-resistant applications. Low TTRA values, when encountered, indicate susceptibility to lamellar tearing but provide little indication of the source of premature fracture. Fractographic examination, especially with the scanning electron microscope, provides information about the origins of low ductility. Sources of premature fracture discussed herein are indigenous inclusions, exogenous inclusions, occluded hydrogen, undissolved alloy additions, and solidification microvoids.
Stressing for Test Purposes of Materials in Tubular Form Using Elastomeric Inserts—Practical Testing Procedures
Authors: Mosley K
Published: February 2009

This paper describes mainly the practical aspects of a simple and rapid method of elastic hoop stressing materials in tubular form using elastomeric inserts. The method can be used for stressing to required limits, for testing to fracture, or for obtaining yield loads. It is extremely suitable for the testing of brittle materials. Stress equations and insert specimen coefficients of friction are given in the appendixes.
A Pilot Experiment to Determine the Feasibility of Reconstituting Tested Irradiated Charpy V Specimens
Authors: Burch PR
Published: February 2009

The role of the Charpy V impact test specimen is well established in irradiation studies of reactor pressure vessel materials and forms the basis for the safety justification of light-water reactor pressure vessels throughout their service life. This report details the experimental work carried out towards determining the feasibility of reconstituting further Charpy V specimens from previously tested Charpy V specimens. In this pilot study each broken half of an A533(B) (Unified Numbering System [UNS] K12539) type plate and a submerged are weld metal Charpy V specimen was electron beam welded between two extension pieces of compatible material (A533(B) plate) with matching cross section. After minimal machining each reconstituted Charpy V specimen was impact tested. To validate this technique, broken halves of three high and three low energy Army Materials and Mechanics Research Center (AMMRC) standardized calibration Charpy V specimens were also reconstituted. In addition, a simple photoelastic study was carried out on a replica Charpy V specimen made from birefringent material. This was an attempt to assess the minimum size of test material that could be reconstituted into a Charpy V specimen. In all instances the results were extremely encouraging, especially in the case of the reconstituted AMMRC specimens, and indicated both the feasibility and validity of reconstituting tested Charpy V specimens of low alloy steel reactor pressure vessel type materials. In addition, it is apparent that as small as a 10-mm “insert” of test material could be successfully reconstituted. The results are discussed and speculation made as to the potential use of this technique with respect to irradiated material.
Piston Ring Deposits When Using Vegetable Oil as a Fuel
Authors: Pestes MN , Stanislao J
Published: February 2009

This paper documents the presence of piston ring deposits responsible for sticking piston rings in the diesel engine when using a vegetable oil-diesel fuel blend. It was found that piston ring immobilization is caused by carbon buildup on the combustion chamber side of the rings and in the annular space behind the rings. The carbon buildup is postulated to be the result of a polymerization growth process on preferred metallic surfaces. Most of the growth takes place on the relatively more stationary piston groove rather than on the ring. Carbon buildup preference was found for aluminum rather than cast iron at a common junction of the two metals. Possible solutions to these major problems are summarized.
Fitting of Fatigue Curves with Nonconstant Standard Deviation to Data with Runouts
Authors: Nelson W
Published: February 2009

This paper presents maximum likelihood methods and a computer program for fitting fatigue curves with nonconstant standard deviation to data with runouts. The methods yield estimates and confidence limits for curve coefficients and percentiles of the life distribution at any stress level. Also presented are (1) the likelihood ratio test for comparing the fit to data of different types of fatigue curves and (2) graphical analyses of residuals to check the assumed fatigue life distribution, to assess fit of a curve, and to spot peculiar data.
Measurement of Organic Halide Content of Aqueous and Solid Waste Samples
Authors: Riggin RM , Lucas SV , Jungclaus GA , Billets S
Published: February 2009

This paper describes a series of studies involving the use of “surrogate” methods for the determination of total organic halides, purgeable organic halides, and solvent-extractable organic halides in wastewater and solid wastes. A pyrolysis/microcoulometric system was used as the analytical detection device for all studies. Method performance data are presented for the various surrogate methods. The results obtained with the surrogate methods were compared to those obtained with compound-specific methods based on gas chromatography or combined gas chromatography-mass spectrometry. The advantages and limitations of using the surrogate methods in place of more sophisticated procedures are discussed.
Current Research into the Potential for Utilization of Mine Waste
Authors: Bloomfield RA
Published: February 2009

The disposal of mining waste material in a structurally and environmentally safe manner has become an increasingly important problem. Whenever possible, potential use or reuse methods should be considered. This paper describes current research on four potential waste utilization techniques, namely (1) high-volume end uses for phosphogypsum waste, (2) underground backfilling with tailings or coal refuse, (3) use of mill tailings as a surface backfill, and (4) recovery of energy from controlled burnout of abandoned coal mine fires or coal refuse banks.
Progress in Inductively Coupled Plasma Analytical Spectroscopy
Authors: Barnes RM
Published: February 2009

Although substantial progress has been achieved in inductively coupled plasma (ICP) spectroscopy placing it among the principle spectroscopy tools in analytical research and applications laboratories, some limitations exist especially for the analysis of ultratrace concentration levels in minute samples. The application of chemical and instrumental techniques to enhance the concentration levels of analytes is practical but complicated by the requirements of maintaining the multielement nature of ICP spectroscopy. Various approaches are described to extend the use and reduce the limitations of ICP atomic emission spectroscopy.
Principles on Analysis by Spark Sampling and Plasma Excitation as Applied to Super Alloys
Authors: Beaty JS , Belmore RJ
Published: February 2009

During the last two years, a new concept of metal spectrochemical analysis has emerged. Fundamental to the concept is separating the process of sampling a material from the process of causing the eroded material to emit light. During the analysis sequence, a spark source samples a metal rapidly and precisely. The atom clusters eroded from the sample are introduced into an inductively coupled argon plasma (ICAP) source. The ICAP atomizes the clusters and excites the atoms with minimal matrix effects. It causes the resultant atoms and ions to emit light linearly over four to five orders of magnitude in concentration. Secondary to the evolution of this method of analysis is the identification, quantitation and control of four parameters: (1) the amount of sample eroded per unit time (sample uptake), (2) the influence of an interfering species on the signal measured at the detector of another species (interelement effect), (3) contamination from the residue of a previous sample (sample cross talk), and (4) change in the amount of sample eroded by spark sampling over time (sampling time dependence). It is important to the method that the following assumptions prove to be correct: (1) the atom clusters erode from the sample and have the same composition as the sample itself and (2) all of the elements in the sample are determined during the analysis. The analytical method that results from the separation of sampling and excitation, the control of the four parameters, and the validity of the two assumptions are capable of minimizing matrix effects in optical emission metals analysis. By using the method, an analyst can calibrate or standardize with one kind of material, such as low alloy steel, and analyze another, such as Waspaloy. The utility of this form of metals analysis, separate sampling and excitation analysis (SSEA), will be demonstrated by examining the methodology and results of low alloy steel, Waspaloy, and Rene analysis.
Quantitation of Carbon in Oil Shale Process Wastewaters: Coulometry Coupled with Ultraviolet-Peroxydisulfate and High-Temperature Oxidation
Authors: Langlois GW , Jones BM , Sakaji RH , Daughton CG
Published: February 2009

Wastewaters from the production of synfuels, in particular oil shale retort waters, present several major problems to various instrument configurations designed for carbon analysis. A carbon analyzer was fabricated from commercially available oxidation and detection units. Carbon oxidation occurred in an ultraviolet (UV) photochemical reactor using acid peroxydisulfate; quantitation of the evolved carbon dioxide was accomplished with an automatic coulometric titrator. This new design eliminated the problems of (1) instrument downtime caused by fouling of high-temperature combustion catalysts and corrosion of furnace combustion tubes, (2) limited linear dynamic range and upper detection limit (namely, infrared detection), and (3) frequent detector calibration (namely, infrared and flame ionization detection).

The UV-persulfate/coulometric titration carbon analyzer was compared statistically with a high-temperature combustion system that is suitable for use with an ASTM method on the basis of (1) the accuracy and precision of recovery of total dissolved carbon (TDC) and dissolved organic carbon (DOC) for nitrogen heterocycles, which were of primary interest because of their preponderance in oil shale process waters and their reported resistance to certain oxidation methods, and (2) the precision of TDC and DOC determinations for nine oil shale process wastewaters. Several qualitative considerations are discussed for both analyzers, including ease of operation, instrument downtime, and maintenance costs.
Use of a Portable Vapor Analyzer in Groundwater Contamination Studies
Authors: Petros JK , Beckett JW
Published: February 2009

A portable organic vapor analyzer was evaluated and subsequently used to locate pockets of volatile organics underground. Methods for laying out sampling grinds in the field are described, and the sensitivity of two different analyzers to various volatile organics are compared. Field data are discussed and methods of verifying the analytical results (for example, digging backhoe pits in “clean” and “contaminated” areas) are described. Precautions to be taken when using this type of instrument in the field also are discussed.
Comparison of Nailed Joint Test Methods
Authors: Pellicane PJ , Bodig J
Published: February 2009

Six different test configurations were studied to evaluate the effect of test methods on the load-slip behavior of nailed joints. The apparati considered are those used by five researchers in addition to that described in ASTM Method for Testing Mechanical Fasteners in Wood (D 1761). The load-slip parameters evaluated were: first and second cycle secant slip moduli at design load, loads at 0.38- (0.015-) and 2.54-mm (0.100-in.) slip, ultimate load, and slip at ultimate load. These parameters were evaluated for joints nailed with 6d and 8d nails in single shear and interlayer (connector) gaps of zero and 0.51 mm (0.02 in.). Douglas fir lumber and plywood were used as main and side members, respectively. The results indicate that first and second cycle slip moduli are highly sensitive to the test apparatus used. Sensitivity decreases as parameters are taken further along the load-slip record. Beyond 2.54-mm (0.100-in.) slip, no statistically significant differences were found as a result of the methods used. The profound effect of interlayer gap on slip modulus is apparent, while the influence of number of nails used in a specimen is insignificant. Finally, the need for accurate slip measurement and three-point support foundation for test specimens loaded in compression is emphasized.
Insulated Masonry Construction Using Knockout Web Concrete Block
Authors: Crandall JS
Published: February 2009

This paper presents details, experimental data, and evaluation of the performance of single-wythe concrete block wall construction incorporating nearly continuous insulation and thermal breaks between the faceshells and webs of two-core lightweight concrete masonry units. The results of lateral-load tests as well as dynamic heat exchange studies are discussed. Analysis of behavior under load indicates no difference in capacity or failure mode for the insulated block units when compared with conventional concrete masonry construction of comparable weight, thickness, and material properties. Overall conductance of insulated units is reduced 10 to 86%, depending on the dynamics of the heat exchange cycle, when compared to conventional units. Proposed refinements in the design of insulated units may achieve thermal performance comparable to “super insulated” construction in other materials.
Rheology of Cold-Recycled Pavement Materials Using Creep Test
Authors: Mamlouk MS
Published: February 2009

The recycling technique of asphalt pavement materials has been used in the past decade, however, unsolved problems still exist such as rutting or instability. The slow reaction of the softening agents or the new binders or both may be responsible for this phenomenon. The viscosity of the binder in the cold-recycled pavement materials mixed with emulsified asphalts is experimentally analyzed by evaluating certain rheological characteristics of the mixture using the creep test at three temperatures. The properties of the recycled mixture are determined at both early and accelerated long-term aging and the results are compared with the properties of virgin materials. Master creep curves are developed using the time-temperature superposition technique. The creep behavior of the recycled asphalt mixture used in this study does not support the hypothesis of the long-term reaction between the emulsified asphalt and the reclaimed materials. In addition, the bulk specific gravity and the retained moisture in the compacted recycled mixture were evaluated at various ages.
Deep-Drawing of Anisotropic Work-Hardening Sheet Metals Into a High-Pressure Medium
Authors: Bayoumi MR
Published: February 2009

Theoretical studies for the pressure-assisted deep-drawing operation have been conducted to determine the largest cup that could be drawn for different materials. Theoretical results for materials characterized by material constant n values and normal anisotropy R values were obtained considering the coefficient of friction μ as 0.0, 0.05, 0.1, and 0.2 values. Tensile instability is shown to be the most appropriate condition in controlling the limiting drawing ratio for the pressure process. Smooth and rough, hemispherical and conical headed punches were used to obtain practical limiting drawing ratios using different materials and different lubricants. Sheet metals used in this work were annealed 70/30 brass, mild steel, and annealed aluminum. Sheet metals were characterized by the relation effective stress σ = Aεn where A is a material constant and ε is strain. The anisotropy of the sheet metal was measured by R value for the rolling direction, 45° to the rolling direction and perpendicular to the rolling direction. A test rig, with a specially designed relief valve that controlled pressure in a range from zero up to 100 MPa and a specially designed strain gauge load cell, were constructed to carry out the experimental work. The pressure-assisted deep-drawing has been experimentally proven to be successful in obtaining higher limiting drawing ratios when deep-drawing with hemispherical and conical headed punches. Comparison between theoretical results and experimental results and the experiments of previous research workers has demonstrated the importance of taking friction into account in the theoretical analysis.
Computer Identification of Machined Surfaces
Authors: Shetty D , Imbert C
Published: February 2009

This paper highlights a new noncontact technique to assess the differences in surface characteristics of components machined by shaping, milling, turning, and grinding processes. The method suggested here is a laboratory analysis based on the process of intensity Fourier transformation taking place on the surface under testing. The measurements are made on the spatial frequency spectrum of the ground surface as an example, using lasers, rather than on the image of the surface. The results are analyzed by using an in-process microprocessor system to evaluate the surface characteristics immediately.
Evaluation of the Ultrasonic Method for Solubilizing Dapnia magna Before Liquid Scintillation Counting
Authors: Dauble DD , Hanf RW , Carlile DW
Published: February 2009

Adult Daphnia magna were exposed to 14C-labeled phenol and tissues analyzed for 14C uptake by three methods: (1) tissue solubilizer, (2) tissue solubilizer plus sonication, and (3) sonication alone. Analysis by liquid scintillation counting revealed that measurements of total activity among treatments were not significantly different (α ≤ 0.10) at two count levels. Sonicated samples showed less variation than tissue samples that were solubilized.
Processibility Testing of Styrene-Butadiene Rubber 1500
Authors: Karg RF
Published: February 2009

Studies of the rheological behavior upon milling and compounding of styrene-butadiene rubber (SBR) polymers having different molecular weight and molecular weight distribution using the Monsanto processibility tester show that polymers having a high molecular weight fraction have higher stress-relaxation time values, because of the higher degree of polymer entanglements. As temperature is increased, the high molecular friction has less effect on the stress-relaxation time. Polymers not having high molecular weight fractions show viscosity to be directly proportional to stress relaxation values tested on specimens before and after being submitted to polymer breakdown on a lab mill. Experiments measure the degree of high molecular weight breakdown and the chain extension and contraction that occurs during milling and time conditioning. Increasing test temperature shows a decrease in stress relaxation time. Compound viscosity values of polymers having high molecular weight fraction decrease less upon increasing temperatures than polymers having no high molecular weight fraction. The processibility tester can be used to characterize the rheological properties of an elastomer or its compounds. This information can be used to duplicate a “good” processing compound or to detect a “bad” one based on the particular processing requirements.
Deckboard Bending Theory for Three-Stringer Wood Pallets in Drive-In Racks
Authors: Urbanik TJ
Published: February 2009

Wood pallets are increasingly being used in drive-in racks and are often positioned for easy access with supports parallel to the outer stringers. The performance of these pallets is governed by the bending behavior of the deckboards as affected by the distribution of the load and the rigidity of the nailed joints. This report gives design formulas for calculating the short-term constant environmental condition bending stiffness and bending strength of three-stringer pallets used in racks. The formulas treat an arbitrary rigidity of the nailed joints and an arbitrary area of the top deck covered by a uniformly distributed, symmetric, and centrally applied load.
Task Group Report: Results of the Interlaboratory Test Program to Determine Percent Shear of Dynamic Tear Test Specimens
Authors: Lazaridis NA , Heberling TG , Harris ES , Lange EA , Wilson AD
Published: February 2009

ASTM Task Group E24.03.02 on Dynamic Tear Testing evaluated the various procedures used for determining the percent shear fracture surface appearance of dynamic tear (DT) test specimens. The entire gage range of standard DT specimens was investigated. The techniques used ranged from direct visual inspection of the fracture surface to various cleavage area measurement methods using fracture surface photographs. Results based on 35 DT specimens indicated that very consistent and reproducible data can be obtained regardless of the method used. In most cases, either the original or the final specimen cross section can be used as reference, the percent shear results differing by only 5 to 10% between the two areas. Careful visual rating by a trained individual can give results very similar to the more time-consuming methods and is acceptable in most cases. Based on these results a set of recommended procedures was appended to ASTM Test Method for Dynamic Tear Energy of Metallic Materials (E 604) under the title, Determination of Percent Shear Fracture Appearance.
Analysis of Hot Tension Test Data To Obtain Stress-Strain Curves to High Strains
Authors: Plaut RL , Sellars CM
Published: February 2009

High strain rate hot tension tests have been carried out on AISI 1020 (Unified Numbering System [UNS] G10200) steel using a Gleeble® testing machine. Tests have been terminated at a series of strains and the specimen geometries measured. From these measurements, local areas, strains, and strain rates are derived and are used to obtain the local true stress-true strain curves. These are corrected for the change in strain rate with strain using an equation of state. The corrected curves are in good agreement with published curves on similar steels determined by compression or torsion testing. Under the present testing conditions, the maximum strain to which correction can be applied is ∼ 1.5. This is imposed by the onset of rapid local deformation heating. Up to this strain, no stress correction of the Bridgmann type for necking appears to be necessary.
A Comprehensive Viscoelasto-Plastic Characterization of Sand-Asphalt Compressive and Tensile Cyclic Loading
Authors: Sides A , Uzan J , Perl M
Published: February 2009

A comprehensive constitutive law for a sand-asphalt mixture subjected to either compressive or tensile cyclic loading is developed. The elastic, plastic, viscoelastic, and viscoplastic strain components are incorporated into the model as they are found to be simultaneously present during the loading process. The various parameters of the model are extracted from a series of repeated uniaxial creep and creep-recovery experiments performed under either compressive or tensile constant stress. The experiments are conducted at constant temperature and at various stress levels, time periods, and number of cycles. The material law presentation is followed by a parametric study that is intended to illustrate the relative quantitative influence of various parameters on the resilient and residual strain components.
Evaluation of In-Situ Pavement Moduli from Deflection Measurements
Authors: Mamlouk MS
Published: February 2009

At present, there is no direct solution that provides the pavement in-situ layer moduli from deflection measurements. Current methods evaluate the pavement layer moduli from deflection measurements using either empirical approaches or layered elastic computer programs with iterative solutions. In this study mechanistically based typical curves are developed to evaluate the moduli of the pavement layers: surface, base, subbase, and subgrade from surface deflection measurements. The curves are developed using the Chevron N-layer computer program with a large number of typical combinations of layer thicknesses and material moduli. The load is assumed to be uniformly applied on a single circular plate with a 304.8-mm (12-in.) diameter, a typical condition of the falling weight deflectometer and the road rater with a single circular plate. Twenty-four sets of curves are developed representing a wide range of layer thicknesses and deflection basin shapes. Therefore, if the layer thicknesses are known and the surface deflection measurements are determined, the four moduli of the pavement layers can be evaluated. The developed curves are simple to use without the need for previous empirical relationships or computer analysis. The curves developed here are based on static analysis.
Simple Determination of the Effective Young's Modulus of Rock by the Compliance Method
Authors: Hashida T , Takahashi H
Published: February 2009

A simple procedure for the determination of the effective Young's modulus of rock is presented. The method uses the elastic compliance calibration of fracture toughness test specimen geometry. Specimen compliance is measured with various sized three-point bend and compact tension specimens of granite. The experimental results show that the deformation behavior of the granite is significantly nonlinear and the specimen compliance is dependent on the loading level. A sharply notched specimen is successfully used to determine the effective Young's modulus rather than a fatigue precracked one because of the strong effect of fatigue loading on the specimen compliance. The effective Young's modulus evaluated by the compliance method coincides well with the Young's modulus determined from uniaxial tension tests and shows no specimen size or geometry effects. The effect of water environment on the effective Young's modulus is also investigated by this method.
Review of ASTM Test for Surface Burning Characteristics of Building Materials (E 84) (An ASTM White Paper)
Authors: Abrams MS , D'Souza MV , Higginson P , Metes WS , Quintiere JG , Parker WJ , Robins RF , White JA
Published: February 2009

This review of ASTM Test for Surface Burning Characteristics of Building Materials (E 84) is intended to provide a source document on the 25-ft tunnel test method as well as to provide a basis for its evaluation by ASTM Subcommittee E05.32 on Research. It covers the history of ASTM E 84 including its development and acceptance by the regulatory authorities. It describes the test method as it exists today and the current operational and calculational procedures. It discusses the work of the tunnel operator's task group in continually reviewing the method, conducting research, and proposing revisions for consideration for adoption by ASTM Committee E-5 on Fire Standards. The effect of air velocity, burner gas flow, and other variables on the results of the test and the reproducibility between testing laboratories is discussed. The correlation of the results of the tunnel tests with those of room and corner tests is presented. The present state of the analysis of the tunnel is described. The efforts to determine the total quantity of smoke produced during the test by improving the photometer system, eliminating stratification, and changing the calculational procedures are discussed. The oxygen consumption method for determining the total heat contribution is described. The benefit of reporting the rate of flame spread as well as the flame spread index (FSI) is pointed out. The advantages and disadvantages are discussed. A list of ASTM E 84 test facilities along with the person to contact is provided. A comprehensive bibliography of the tunnel is included.
Determination of Crack Growth Parameter N in Ceramics Under Creep Conditions
Authors: Fett T , Munz D
Published: February 2009

In cases of linear-elastic material behavior the parameter N of subcritical crack growth is often determined by dynamic bending tests with different loading rates. At high temperatures the obtained results are influenced by creep effects. A procedure is described to evaluate N under creep conditions by correction of bending strength and loading rate.
Fracture Toughness of Hot-Pressed Beryllium
Authors: Lemon DD , Brown WF
Published: February 2009

This paper presents the results of an investigation into the fracture toughness, sustained-load flaw growth, and fatigue-crack propagation resistance of S200E hot-pressed beryllium at room temperature. It also reviews the literature pertaining to the influence of various factors on the fracture toughness of hot-pressed beryllium determined using fatigue-cracked specimens.
Instrumented Impact Testing of Steel Plate
Authors: Shimizu H , Gibbon MW
Published: February 2009

Instrumented impact testing should be a basic component of fracture resistance evaluation. However, the output signals from an instrumented tup can be difficult to interpret unless precautions are taken to minimize spurious signals generated by extraneous effects. Instrumented drop-weight tear testing (DWTT) was used to study the fracture behavior of G40.21-44T construction grade steel. The fracture process was monitored in detail by means of high-speed photography at 6000 frames per second, and correlated with the output traces from the Dynatup 8000 impact testing machine. The traces were analyzed with reference to the dynamic response characteristics of the machine/specimen system and compared with the output traces derived from instrumented specimens. The results of visual observation of the fracture process together with the output traces of load and strain-transducers provide strong evidence that the peak load coincides with crack initiation in this steel. The spurious signals are related primarily to the mechanical characteristics of the testing machine and to specimen oscillations.
Preparation of Impact Specimens from Cast Austenitic Manganese Steels
Authors: Ghoreshy M , Mackay WBF , Smith RW
Published: February 2009

A method is described for the preparation of Charpy impact specimens suitable for screening purposes for a series of small experimental cast austenitic manganese steel heats. The process involves the investment casting of test specimens and notching by means of a computer controlled electrical-discharge-machining (EDM) unit.
Effect of Size on Elastic-Plastic Fracture Toughness Parameters
Authors: Putatunda SK , Rigsbee JM , Corten HT
Published: February 2009

An investigation has been carried out to determine the influence of thickness and width on the elastic-plastic fracture toughness parameters: J value obtained from area under load/displacement curve JR, tearing modulus, and stress intensity factor corrected for plasticity KR. Compact tension specimens prepared from aircraft quality American Iran and Steel Institute (AISI) 4340 (Unified Numbering System [UNS] G43400) steel heat treated to a yield strength of 1000 MPa were used. All specimens satisfied the ASTM Test for JIc, a measure of Fracture Toughness (E 813) standard size requirements.

This investigation demonstrates that when the specimens satisfy all ASTM standard size requirements, ductile fracture toughness JIc is independent of size. JIc values were found to vary a maximum of ±16% of mean value even in the present of some shear lips. Conversely, the tearing modulus was found to decrease as specimen thickness increased. A one to one relationship was found to exist between JR and JK, where JR is the J value calculated from the area under the load/displacement curve and JK is the J value computed from KR using the linear elastic fracture mechanics (LEFM) relationship.
A Positron Study of the Quench and Tempering Process in AISI 4340 Steel
Authors: Moore KD , Jones PL
Published: February 2009

Dopper broadening measurements of the gamma-ray spectra produced by positron annihilation have been made on an AISI 4340 (Unified Numbering System [UNS] G43400) steel as a function of both isochronal tempering over the temperature range of 150 to 700°C and isothermal tempering at 250°C for times ranging from 1 to 1100 min. Changes in the positron annihilation line shape parameter S are correlated with the corresponding structural transformations that accompany tempering of the as-quenched steel. Of particular significance is the increase in the S parameter in the temper embrittlement regime. This increase in S parameter is postulated to be related to the precipitation of a transition iron carbide that alters the defect structure of the surrounding ferrite phase.
Effect of Crack-Tip Morphology on Cleavage-Crack Extension
Authors: Rosenfield AR
Published: February 2009

Values of fracture toughness obtained by cleavage reinitition of arrested cleavage cracks in compact specimens are found to agree with those obtained from thermal shock experiments on much larger cylinders. In contrast, toughness values obtained using fatigue-precracked compact specimens are somewhat higher. It is suggested that the arrested cleavage crack tip is a more potent flaw than the fatigue precrack.
Principles, History, and Status of Dual-Energy Computerized Tomographic Explosives Detection
Authors: Roder FL
Published: February 2009

A brief account is given of the principles of dual-energy computerized tomography (DECT) and of the potential which DECT has demonstrated for the automated detection of commercial and military explosives concealed in suitcases or packages. A description of a breadboard system configured for this purpose is provided and recent advances in the state of the art in CT are discussed in the light of their potential significance for explosives detection.
ASTM Standardization Activities in the Fracture Testing of Beryllium
Authors: Brown WF
Published: February 2009

Interest in beryllium as a structural material stems from its low density (about one-fourth that of steel) and its high modulus (about 1.4 times that of steel). Beryllium also has a very low thermal neutron absorption cross section which makes it vattractive for use as a moderator or reflector in spacecraft propulsion systems employing nuclear reactors. However, structural applications have been limited because of beryllium's low “ductility.”
Ultrasonic Measurement of Elastic Moduli in Slender Specimens Using Extensional and Torsional Wave Pulses
Authors: Lynnworth LC
Published: February 2009

The pulse-echo method using extensional and torsional waves is described relative to determining elastic properties and other characteristics of specimens which are slender acoustically. Several applications are reviewed, including: glass fibers of diameter 16 to 42 μm; glass rods of diameter about 1 mm, tested to 700°C; iron-base alloys of diameter 3.2 mm, tested from nearly −200°C up to +200°C; titanium specimens of rectangular cross section, 1.5 × 3 mm; and tantalum-base alloys of diameter 6.4 mm, tested up to 1400°C. Limitations are pointed out regarding dispersive materials and geometry.
Fatigue Behavior of Solders Used in Flip-Chip Technology
Authors: Rathore HS , Yih RC , Edenfeld AR
Published: February 2009

This paper surveys the mechanical fatigue behavior of 5/95 Sn/Pb solder and solder with copper, silver and palladium impurities at different temperatures and on-off cycling frequencies. Presence of copper in 5/95 Sn/Pb creates hard and relatively brittle intermetallics which also significantly decrease the fatigue life of solder. The fatigue cracks were observed to propagate through grain boundaries, although some slip striations were observed within individual grains. There is a significant decrease in the fatigue life of 5/95 Sn/Pb in the temperature range of 85 C to 150 C. The fatigue life of solder decreases with a decrease in cycling frequency. Results have shown that the frequency exponent is equal to ⅕. Cyclic strain softening was observed in the specimens which were tested under constant total strain control conditions.
Monitoring of Cement Stabilized Surrogate Waste Using Resonant Frequency Techniques
Authors: Mirizzi SA , Baseheart TM , Rieser LA , Kramer TE
Published: February 2009

It is often necessary to track incremental changes in the physical properties of composites with portland cement binders caused by chemical attack, freeze-thaw cycles, and other deterioration mechanisms. The vibration testing procedure presented for measuring the resonant frequency of a specimen is directly applicable to the monitoring of the deterioration of stabilized/solidified waste specimens. The change in the fundamental frequency is significantly more sensitive than the loss of mass to the internal changes in the mechanical properties of specimens. The time and effort required to determine the fundamental frequency of a specimen is also significantly less than that required to determine the loss of mass of the same specimen. The proposed method has been demonstrated to work on small cylindrical specimens (44 mm by 74 mm) with aspect ratios less than 2.0. The use of elastomeric bands as the means of attachment of the specimen to the test equipment does not interfere with or limit other chemical and mechanical performance tests scheduled for the specimens.
A Vibration-Based Method for Determining St. Venant Torsional and Warping Stiffnesses of Members with Open Cross-Sections
Authors: Li D-B , Chui YH , Smith I
Published: February 2009

A dynamic mechanical property identification method is presented based on a study of composite wood members with an open I-shape cross-section. Besides the bending stiffness which is identified by a bending vibration test, St. Venant torsional stiffness GKs, and warping stiffness EKw are identified by a separate torsional modal analysis. Three kinds of typical I-shape beams have been tested and their properties identified. The approach is based on Euler beam theory and an earlier torsional vibration model developed by the authors.
Interlaboratory Study of Strain-Cycle Fatigue of 1.2-mm-Thick Sheet Specimens
Authors: Miller GA
Published: February 2009

Five laboratories undertook a study to assess interlaoratory variability and bias in strain-cycle fatigue testing of 1.2-mm-thick sheet specimens. In addition, one laboratory evaluated the effects of specimen geometry, actuator restraint, extensometer mounting surface, etc., on validity and bias of cyclic stress-strain and strain-life data. The results show that the cyclic stress-strain curve is sensitive to the effects of interlaboratory differences. The strain-life curve is also affected by results from different laboratories, but in addition it is sensitive to testing variables such as extensometer mounting surface, failure criterion, specimen, geometry, etc. The results of this study have implications for the development of a test method and for the use of strain-cycle fatigue data obtained from thin sheet specimens. The results reported here form a basis for expanding ASTM Recommended Practice for Constant-Amplitude Low-Cycle Fatigue Testing (E 606) to include materials with thicknesses less than 2.5 mm.
A Single-Specimen Determination of JIc by the Ultrasonic Method and Analysis of Its Statistical Distribution Characteristics
Authors: Hirano K , Kobayashi H , Nakazawa H
Published: February 2009

This paper reports the summary of JIc test procedures based on an ultrasonic method proposed earlier. The single-specimen JIc measurements for low- and intermediate-strength, high-toughness materials show excellent agreement with those determined by multispeciment test procedures. The JIc values of the weldment were also determined from a single specimen. In addition, a statistical analysis of the JIc distribution was done.
Optical Measurement of Granite Surface Polish
Authors: Gascón F , Balbás M
Published: February 2009

An optical method to measure granite surface finish is described. This method is capable of ordering the different varieties of granite subjected to the same industrial finishing process consistently with an arrangement made by an average human observer.

The measure of finish is defined as the ratio between the specularly reflected luminous flux from a sample and the total diffused light. Some recommendations for the standardization of measurements are given.
Nondestructive Evaluation of Bond Quality of Bimetallic Strips Using Acoustic Emission
Authors: Murthy CRL , Brahma KK
Published: February 2009

Acoustic emission (AE) appears to hold good promise for nondestructive evaluation of bond strength of bimetallic strips in two ways: (1) as a quality control tool in batch sampling and (2) as a 100% inspection method. A program has been initiated at the Aerospace Engineering Department of the Indian Institute of Science to explore the feasibility of utilizing the acoustic emission technique for evaluation of bond strength of bimetallic strips. As a first step, acoustic emission was monitored during tensile testing of copper-lead bimetallic strips. The results obtained during these tests indicate differences in AE activity between specimens with poor and good bonding at very small loads which can be utilized for inspecting the bond quality.
Test Method for Evaluation of Shear Modulus and Modulus of Elasticity of Laminated Anisotropic Composite Materials
Authors: Cheng S
Published: February 2009

A test method for the determination of the shear modulus and the modulus of elasticity of laminated anisotropic composite materials is presented. Two tests are required. In one test, a ring is simply supported at two diametrically opposite supports and subjected to two diametrically opposite concentrated loads normal to the plane of the ring and located 90° from the supports. The second test employs a split ring. Each end of the ring is subjected to a concentrated load normal to the plane of the ring. By conducting these two tests and measuring the normal deflections corresponding to the applied loads, shear modulus and modulus of elasticity of the ring can be determined from the formulas derived in the paper. It should be noted that for laminated composite anisotropic materials these moduli cannot be determined from the tests as known in the literature, one of which involves out-of-plane loading and the other an in-plane loading as suggested in Paper 4709, Douglas Missile and Space Systems Division, McDonnell Douglas Corporation, November, 1967.
Effect of Dither on Strain-Controlled Fatigue and Tensile Results Obtained with a Closed-Loop Servohydraulic Testing Machine
Authors: Bush RW , Quesnel DJ
Published: February 2009

The flow stress of alpha brass was found to decrease during strain-controlled tension tests when the dither amplitude was increased. It is suggested that when conducting such tests using specimens requiring low deformation loads that alternative means of preventing silting be used.
Modulus Measurements in Ordered Co-Al, Fe-Al, and Ni-Al Alloys
Authors: Harmouche MR , Wolfenden A
Published: February 2009

The composition and/or temperature dependence of the dynamic Young's modulus for the ordered B2 Co-Al, Fe-Al, and Ni-Al aluminides has been investigated using the piezoelectric ultrasonic composite oscillator technique (PUCOT). The modulus has been measured in the composition interval 48.49 to 52.28 atomic % Co, 50.87 to 60.2 atomic % Fe, and 49.22 to 55.95 atomic % Ni for Co-Al, Fe-Al, and Ni-Al, respectively. The measured values for Co-Al are in the temperature interval 300 to 1300 K, while those for the other systems are for ambient temperature only. The data points show that Co-Al is stiffer than Fe-Al, which is stiffer than Ni-Al. The values reported herein for Co-Al are the first of their kind, since none has been reported earlier. However, the data points for Fe-Al and Ni-Al are slightly higher than those reported in the literature.
Effect of Rε on Cyclic Stress-Strain Behavior of Inconel 718
Authors: Cook TS
Published: February 2009

This investigation was undertaken to examine in detail the effect of the strain ratio, Rε =εmin/εmax, on the cyclic behavior of Inconel 718 at 566°C. The results showed that the cyclic properties defined by the amplitude of the load-displacement hysteresis loops are independent of the mean stress. The complete cyclic curve, defined by the tips of the hysteresis loops, does depend on Rε at small strain ranges. At larger strain ranges where the plastic deformation allows the mean stress to relax, the effect disappears.
Determination of the Critical Value of the J-Integral at High Loading Rates Using the Wedge-Loaded Specimen
Authors: Klepaczko JR
Published: February 2009

A novel procedure is proposed, which improves an earlier one, to determine the critical value of the J-integral at high loading rates. A more detailed analysis of such a test along with some experimental results has been published elsewhere. The present procedure is based on ASTM Test for JIc, a Measure of Fracture Toughness (E 813). To perform the impact test, the split Hopkinson pressure bar concept is used together with the wedge-loaded compact tension specimen (WLCT).

This paper provides a better understanding of the proposed procedure by a more accurate analysis of the frictional effects which occur between the loading wedge and the WLCT specimen. In addition, a unique procedure has been developed to measure the coefficient of Coulomb friction in the real environment of fracture KIc or JIc tests.
System for the Adaptation of Tensile Testing Machines for Executing Torsional Tests
Authors: Wolfseher R , Inhelder J , Helbling AK
Published: February 2009

The torsion testing system “TS-X 100” is described. It is a simple system in which tensile testing machines can readily be adapted for executing torsional tests and, in particular, for carrying out inexpensive long-time torsional tests. The system is very compact and can be installed in a testing chamber to obtain precisely defined boundary conditions. Purely torsional loadings were obtained by loading a horizontal “free suspended” specimen through opposing force couples of equal magnitude.

Depending on the loading range, an optimized system can easily be built with a stronger structure and/or longer lever arms to increase the magnitude of the applied force couples. Calibration and creep tests confirmed the suitability of the system.