bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Pile Group Behavior
Authors: Nair Keshavan , Gray Hamilton , Donovan N. C.
Published: August 2009

A procedure for the three-dimensional analysis of pile groups subject to horizontal and vertical forces and moments which accounts for batter piles, the flexural resistance of the piles, and the lateral resistance of the surrounding soil is discussed. Due to the extensive amount of computational effort required to analyze a pile group, the analysis was programmed for a digital computer. Since many of the factors involved in the design of pile foundations are not known with great accuracy, the use of the digital computer permits the esigner to examine the effect of variations in various design parameters. This paper presents results obtained from analyzing several pile group arrangements for various soil and loading conditions. The results obtained from the analysis include the axial loads, moments, stresses, and deflections for individual piles, as well as for the group. The numerical results obtained from analyzing various illustrative examples show the significant influence that the following factors have on the loads that are introduced in the various individual piles: (a) the arrangement of the individual piles within the group, (b) the end condition as reflected by the connection between the pile cap and the piles, (c) the lateral resistance of the surrounding soil, and (d) the flexural resistance of the pile. Comparison with field and laboratory tests indicates that the behavior of pile groups predicted by the analysis is in qualitative agreement with observed behavior. This paper demonstrates that it is possible to use the pile group analysis presented as a practical method for solving design problems. The ability to evaluate variations in design parameters should lead to safer and more economical designs.
Instrumentation and Downdrag
Authors: Crawford C. B.
Published: August 2009

The distribution of downdrag on end bearing and friction piles is explained and illustrated. From the meager published information and experience some of the important factors affecting field measurements and their interpretation are given.
Dynamic and Earthquake Forces on Deep Foundations
Authors: Nair Keshavan
Published: August 2009

This paper reviews briefly the state-of-the-art in two aspects of the design of deep foundations for dynamic and earthquake loads: (a) definition of the loads and (b) methods of analysis. These are placed within the general context of foundation design. Included in this review are comments on the papers presented to this session of the symposium. Presently used methods for describing dynamic loads in foundation analysis are examined, and it is pointed out that techniques for defining wave and seismic loadings need improvement and that statistical methods should, when possible, be utilized in defining these loads. Methods of analysis are reviewed, and it is concluded that numerical methods based on the lumped mass and finite and discrete element techniques appear to offer the greatest potential for use in the design of deep foundations under dynamic loads.
Pile-Soil System Response in a Cohesive Soil
Authors: Airhart T. P. , Coyle H. M. , Hirsch T. J. , Buchanan S. J.
Published: August 2009

This paper presents an investigation into the loading response of a saturated, cohesive soil medium associated with a pile-soil system. An instrumented test pile was driven in order to determine the adequacy with which proposed theories describe the field response of a pile-soil system. The test pile was a 50-ft-long 16-in.-diameter steel pipe in which strain gages, accelerometers, and pressure transducers were installed. Field tests were performed at Beaumont, Tex., in a marine clay deposit. Stresses and accelerations developed in the pile were measured during driving. Pore water pressures were measured after driving for a period of approximately four weeks, or until the excess pore water pressure resulting from driving had dissipated, and during static load tests. Samples were taken of soil about the pile in various states of disturbance which varied with time and radial distance from the pile. Measurement of the engineering properties of these samples furnished an evaluation of the effect of different degrees of soil disturbance. Results obtained in this study indicate that soil disturbances and resulting excess pore water pressures associated with the driving of a large diameter pile are of greater magnitude and dimensional extent than previously thought. An evaluation is presented of the magnitude and general nature of the soil response to dynamic loadings of driving. Finally, results of static load tests performed approximately two and four weeks after driving furnish a measurement of ultimate bearing capacity as a function of time after driving.
Driving Resistance and Bearing Capacity of Vibro-Driven Model Piles
Authors: Schmid W. E.
Published: August 2009

The driving resistance of a vibro-driven pile is analyzed by establishing a dynamic force equilibrium between the vibratory exciter force, the inertia forces, and the soil resistance as a function of time for a rigid body type of pile vibration. The driving resistance has a periodic variation and depends on the vibratory velocity of the pile. For each cycle the motion of the pile must be such that the velocity at some time is zero. It is at these instances that the viscous resistance also must be zero, and the only resistance to pile penetration remaining must be the static bearing capacity. A series of model experiments were performed during which the dynamic force input, the acceleration, and the point resistance of a model pile were measured. The results show a comparison between calculated and observed values for driving resistance and bearing capacity.
Relationship Between Precipitation and Dimple Fracture in an 18 Percent Nickel Maraging Steel
Authors: Roesch L. , Henry G.
Published: August 2009

Electron microfractography has been used to study ductile fracture in maraging steel. The conditions under which the cavities, responsible for this type of fracture, can be initiated at precipitates formed during the aging treatment at 475 and 525 C (890 and 980 F),have been investigated. To this end, the microstructure has been examined as a function of aging time, and the mechanical properties and fracture appearance have been studied for different aging times and test temperatures. The fracture surface is always dimpled: for relatively short aging times the dimples are large and irregular in size; in the overaged condition the fracture surface consists of very fine dimples, and there is a good correlation between precipitates and dimples. It is concluded that cavities can be initiated on precipitates only if these particles are larger than a critical size. Qualitatively, similar results have been obtained for other precipitation hardened alloys. The critical size decreases as the test temperature is lowered. It may also depend on the shape of the particles and other factors such as the nature of the precipitates and the particle-matrix interface. Certain aspects of the changes in mechanical properties with heat treatment can be explained in terms of the existence of a critical particle size for cavity nucleation.
Fractographic Studies on the Cleavage Fracture of Single Crystals of Iron
Authors: Kitajima K. , Futagami K.
Published: August 2009

A critical experiment is presented for the mechanisms of initiation and propagation of cleavage crack in iron. At first, precise fractographic observations are made on the type of the origin of crack observed on single crystals of iron with notch. A number of cleavage facets are started from the boundary of a twin, and a straight groove runs through close to the center of the twin. Striations cross the twin with the appearance of shear fracture inside the twin. A possible interpretation for the process of fracture is presented. Secondary, the arresting phenomenon of the fast propagating cleavage crack, together with the nature of plastic deformations produced near the surface of the crack, is studied on the plate of single crystals of iron with large temperature gradients. The surface of cleavage is characterized by the high density of fine twins in the region of low temperatures −196 to 0 C and the apparent smooth surface lacking twins in the regions of high temperatures 100 to 300 C. Etch pit studies, however, revealed the high density of dislocations (109 to 1010 /cm2) confined within a layer of about 3 μm in the later region. From these evidences it is concluded that the nucleation of dislocation loops is a more dominant cause in the plastic deformations than the multiplication of dislocations from the pre-existing dislocations near the crack tip.
Correlations Between Fractographic Features and Plane-Strain Fracture Toughness in an Ultrahigh-Strength Steel
Authors: Spitzig W. A.
Published: August 2009

Fractographic analyses have been conducted on fracture surfaces produced by plane-strain fracture-toughness tests on notched tension-test specimens of 0.45C-Ni-Cr-Mo steels with different sulfur contents (0.008, 0.025, and 0.049 percent), tempered at 400, 800, and 900 F, to establish a relationship between features of the fracture surfaces and the plane-strain fracture-toughness parameter (KIc). The primary differences in the fracture-surface topography among the specimens with different sulfur levels and different tempering treatments were: (1) an increase in number and a decrease in the spacing of sulfide-nucleated dimples with increasing sulfur content and (2) a decrease in the extent of a “stretched” zone between the fatigue-crack and overload-fracture regions of the fracture surface. For each tempering temperature, the plane-strain fracture toughness decreased with a decrease in average sulfide spacing (that is, with an increase in sulfur content). Although, as expected, the sulfide spacing did not change with tempering temperature, the extent of the stretched zone increased with increasing tempering temperature from 800 to 900 F and, therefore, with increasing fracture toughness. A stretched zone was not observed in the steels tempered at 400 F (those with KIc values about 50 ksi√ in. and below). Comparisons of the variations in the size of the stretched zone with the process-zone size and the crack-opening displacement models for planestrain fracture toughness of these 0.45C-Ni-Cr-Mo steels indicated that the variations in the stretched-zone size were in good agreement for both models. Therefore, this stretched zone appears to be related to the size of the zone of plastic instability at the crack tip just prior to unstable fracture. The sulfide-particle spacing did not show good quantitative agreement with either the process-zone size or the crack-opening displacement. The deleterious effect of sulfide particles on plane-strain fracture toughness appears to be related to a decrease in fracture strain with increasing sulfide content that results in a decrease in the zone of plastic instability at the tip of a crack.
Fracture Surface and Processes in Polycarbonate
Authors: Jacoby G. H.
Published: August 2009

Several fracture mechanisms in polycarbonate are demonstrated on the basis of microfractographic methods using light microscope as well as transmission and scanning electron microscope techniques. Various types of fracture surfaces, produced by single cycle overload in normal and corrosive environment and by impact loads, are discussed. The main interest, however, is concentrated on the fatigue fracture surfaces and the fatigue striation feature.
Introduction
Authors: Heine H. J.
Published: August 2009

Many technical papers, lectures, and magazine articles have extolled the significant technological accomplishments and the progress achieved by the ferrous castings industry through years of metallurgical investigation and process development. However, design engineers, castings buyers, and purchasing agents, as well as potential users of cast parts, generally, are not always aware of the strides that have been made and the increasing usefulness of castings as reliable engineered components for sophisticated structures. Research—both fundamental and applied—has broadened our scientific knowledge, many new manufacturing methods have been introduced, and more efficient production equipment has been developed, all resulting in better products and wider product acceptance by our customers. Neither ductile, gray, nor malleable iron should be thought of in terms of representing a single material of construction, rather, each is a collective noun for a family of alloys specifically designed to satisfy certain engineering requirements. Casting high-carbon ferrous materials ceased to be an art quite a few years ago. It is now a science, and one of the major purposes of this publication is to demonstrate this fact. Ferrous castings, if properly designed, have many characteristics which make them desirable for components that are used in transportation, communication, agriculture, construction, power generation and transmission, and in industry, generally. It is recognized that, among the manufacturing processes available, metal casting provides engineers with one of the most versatile of all methods for shaping metals. Castings offer an immense variety of engineering design opportunities and metallurgical properties. In support of this contention, the present book is submitted.
Malleable Iron
Authors: Heine H. J.
Published: August 2009

During the past 20 years, the malleable iron-founding industry has experienced technical developments which have fundamentally altered both the character of the industry and its products. The unique combination of engineering properties for a cast metal is summarized for ferritic and pearlitic malleable iron, and the structural characteristics of the material are reviewed. New design techniques recognize the significance of molding aggregate and metallurgical factors, and the importance of the “feeding path” and “freezing order” concepts is emphasized. Recently developed machinability information is presented in tabular form, and reference is made to the general process capabilities of high-volume malleable iron casting producers for use by casting designers and engineers. New information on fatigue life of as-cast surfaces and postforming operations is discussed.
Field Testing of Components
Authors: Olberts D. R. , Tucker L. E.
Published: August 2009

Current methods of field testing components in agricultural and industrial equipment are described in this paper. This presentation concentrates on experimental methods in which instrumented components are studied with experimental load and stress analysis techniques. It does not cover standard product engineering durability-type testing in which components are run under actual operating conditions for an extended number of hours to assess their durability. The first part of the paper outlines field test techniques, instrumentation, and mobile test laboratories. More specifically, methods of using brittle coatings to locate highly stressed areas will be outlined along with field strain gaging techniques. The use of oscillographs and tape recorders located in an instrument van, which follows the product under test, will be shown. Differentiation will be made between tests used to directly estimate component fatigue life and tests which are used to accumulate load data to confirm theoretical design analysis or to set up durability tests in the laboratory. Because these test procedures are intimately associated with the subsequent use of the test data, the second part of this paper will describe the methods of analyzing the data to make life decisions and will include a description of laboratory materials properties tests and component tests which provide the necessary fatigue life data against which the field test data are compared. The final part of this paper will cover some of the new methods being studied to automate the reduction of field test data through the use of computers.
High Factors of Safety or Usable Design Strengths
Authors: Caine J. B.
Published: August 2009

There can be no question about the decrease in design efficiency because of the use of ideal mechanical properties listed in the handbooks plus nebulous factors of safety based solely on experience. This practice imposes special difficulties for the younger engineers. Would it not be better to use factual strengths based on tests of specimens representing actual parts rather than the highly polished specimens? If the following factors are observed, handbook yield strengths and moduli of elasticity are ensured in cast, wrought, and welded parts: 1. Ensured hardness by testing the parts 100 percent if necessary. 2. No gross surface defects. 3. No crack-like defects that are improperly oriented in highly stressed areas. 4. Not more than 50 percent of the section removed by machining. If these four precautions are observed, proof will be offered that, if the stress concentration is kept under 1.5, design strengths for a typical “soft” steel can be increased from the present nominal 15,000 to 20,000 to 25,000 psi.
Fundamentals of Dynamic Properties Measurement of Elastomers: Part I—Measurement and Identification Principles
Authors: Leonard Robert G.
Published: August 2009

The basic principles of parameter identification for a first-order dynamic model for an elastomer sample are presented. The measurement requirements for both on-line and off-line testing are discussed briefly in terms of what can be measured and what should be measured.
Fundamentals of Dynamic Properties Measurement of Elastomers: Part II—Instrumentation, Computation, and Compensation
Authors: Nachtigal Chester L.
Published: August 2009

Instrument requirements for determining the dynamic properties of elastomers are particularly stringent because of the inherently low phase shift between force and displacement. Some currently available instruments and their tradeoffs are briefly discussed. A basic concept of employing matching circuits to eliminate the necessity for measuring both of the across variables, namely, position and velocity, is described, as well as the computational circuits to recover the missing variable. A scheme for compensating the phase-lagging characteristics of the transducer-amplifier combination is also presented.
Resonant Beam System Development—Past to Present
Authors: Brouwer Floyd
Published: August 2009

The purpose of this paper is to show the development of the Dynamic Rubber Test Machine as an engineering and production (quality control) tool from the standpoint of a machine supplier. Problems encountered in the design, fabrication, preshipment checkout, and installation of equipment into customer's facilities are discussed. Correlation of equipment is explored as it relates to the dynamic spring rate and the damping constant of elastomer products. Certain techniques and hardware adaptations have aided in improving the repeatability of tests of the resonant beam system. The information given is not intended to be all inclusive, but as a report of the work in this field to date.
Evolution and Uses of Transmitted Force Measurement
Authors: Wilson W. J.
Published: August 2009

It has long been recognized that there are problems in obtaining the desired accuracies in elastomer testing. Improvements in accuracy result from taking direct measurements of the displacement and the load generated across the sample being tested. This more direct method, called the Transmitted Force Method, is traced from its initial concept through its stages of development, by different investigators, to the present state-of-the-art. Included in this discussion is the basic concept and underlying theory of this test method, along with a description of measurement techniques.
Welcoming Remarks at the ASTM/NBS Symposium on Spreading Resistance Measurements Gaithersburg, Maryland June 13, 1974
Authors: French Judson C.
Published: August 2009

Good morning. It is a real pleasure for me to bid you welcome to the ASTM/NBS Symposium on Spreading Resistance Measurements on behalf of the National Bureau of Standards and, in particular, on behalf of the Bureau's Electronic Technology Division. I welcome also your co-host Bob Scace, Chairman of Committee F-l on Electronics of the American Society for Testing and Materials. Sharing this period of welcome with Bob is, I believe, representative of the long continuing cooperation between NBS and ASTM in many fields, always with the common interests of improvements in technology, in methods of measurement and specifications, and in the promotion of sound and effective voluntary standards. Many of you are old friends of NBS and our Division but some are becoming acquainted with us for the first time at this Symposium. I would like to address my first few remarks to these new visitors. I am sure you are aware of the NBS role in maintaining and disseminating the primary standards of measurement for this Nation. But the Bureau carries on an amazingly wide variety of activities in other fields as diverse as pollution control and building research, dental materials and cryogenics, standard reference data and computer research, all stemming from the broad charter established by Congress nearly three quarters of a century ago. Here again in its breadth and subject matter the Bureau's interests parallel those of ASTM to a surprising degree.
Formal Comparison of Correction Formulae for Spreading Resistance Measurements on Layered Structures
Authors: Severin P. J.
Published: August 2009

The spreading resistance of a metal contact on a semiconductor sample is analysed for infinite geometry, with three different boundary conditions: a specified potential of the contact, a uniform contact current density and a current density dependent on contact resistance. The cases of a thin layer on a perfectly conducting substrate and on a non-conducting substrate are analysed each for the boundary conditions of uniform current density and of the current density distribution valid for the infinite geometry. With a perfectly conducting substrate the two boundary conditions yield about 10% difference. With a non-conducting substrate calculations based on both current density distributions produce in the thin layer approximation the same In r dependence required. The constant terms in both approaches are different by 5% and the constant current density result in addition agrees with the result obtained with a totally different transmission-line approach. The actual three-point-probe measurement situation is discussed. The danger of correcting the precise spreading resistance measurement results with an error of 1%, with formulae derived on the basis of a formal model which is sensitive to the choice of the boundary conditions by up to 10%, is stressed. The effects of undefined thickness, bevel edge and transition layer curving upwards are mentioned as further complications.
SRPROF, A Fast and Simple Program for Analyzing Spreading Resistance Profile Data
Authors: Morris B. L. , Langer P. H. , White J. C.
Published: August 2009

The spreading resistance technique is an excellent method of measuring epitaxial resistivity profiles. In many cases it is the only method by which the complete profile may be measured. However, thin film correction factors must be used to convert the spreading resistance into a corrected resistivity. Previous calculations of these correction factors have emphasized a mathematically complex solution which necessitates the use of a large computer. The correction factors used here are calculated from a relatively simple algorithm which allows the use of a minicomputer. A documented program is presented which uses these algorithms. This program, written in FOCAL for use on the PDP8 series of minicomputers, is fast, accurate, easy to use, and provides a complete data reduction system. Examples of corrected spreading resistance profiles are presented, and compared with independent results such as diode C-V and four point probe measurements.
Multilayer Analysis of Spreading Resistance Measurements
Authors: Lee Gregg A.
Published: August 2009

Spreading resistance measurements provide a highly flexible technique for the determination of dopant profiles in semiconductors. However, because each measurement samples a greater depth into the sample than the depth difference between successive measurements, the direct conversion of resistivity readings to dopant concentration values will not yield a correct profile. The technique discussed in this report analyzes direct spreading resistance readings to deduce a “true” dopant profile. The model used is that of circular contacts to a laterally infinite medium which is partitioned vertically into layers of homogeneous resistivity, each layer corresponding to one spreading resistance measurement point. The analysis is performed by a computer program. Some detail in the development of the program is discussed. The results of this analysis technique compare favorably to profile results of other profiling techniques such as capacitance voltage and incremental sheet resistance on profile types to which they can be applied. The program execution time is usually fast enough that the computer charge is less than the direct charge billed for making the spreading resistance measurements.
An Automated Spreading Resistance Test Facility
Authors: White James C.
Published: August 2009

An automated spreading resistance test facility has been designed and constructed at the Allentown Works of the Western Electric Co. This system has been shown to provide a rapid, semi-nondestructive, and reproducible measurement of epitaxial layer resistivity which can be used in a production environment. The system has the advantages of operator independence, well protected probes, and four-inch capability. Surface or in-depth measurements can be performed with on-line calculations of resistivity and impurity concentration. Cycle time is less than five seconds per measurement and system reproducibility is ± 1.3% (lS).
Angle-Bevelling Silicon Epitaxial Layers, Technique and Evaluation
Authors: Severin P. J.
Published: August 2009

The properties of a steel probe for a spreading-resistance system are discussed stressing the effect of micro- and macrocontacts. The need is explained for producing small-angle bevels and a lapping jig for making such bevels is described. With small-angle bevels the slice topography cannot be neglected and a simple instrument is described by which the surface topography of the whole slice can be recorded. By recording the slice topography before and after bevelling the local reduction of thickness by the bevelling process is determined. This method can be used for angles between 1/500 and 1/2000. It is indispensable for the proper interpretation of spreading resistance measurements on bevelled N on N+ junctions.
Spreading Resistance Measurements on Silicon with Non-blocking Aluminum-Silicon Contacts
Authors: Krausse J.
Published: August 2009

The paper concerns the measurement of resistivity fluctuations in n-type silicon starting material in the resistivity range from 1 to 1000 Ω cm. The microscopic resistivity fluctuations that are associated with the well-known striations require a measurement technique of high accuracy and high local resolution. We chose the spreading resistance method. However, in contrast to the conventional method, in which the metal probe is pressed directly onto the silicon surface, we supply the silicon slice with non-blocking aluminum-silicon contacts. The radius of the contact area is exactly defined. Any contact radius can be realized according to the resolution desired in lateral direction and in depth. When the metal probe is applied to the aluminum-silicon contact, the contact is not destroyed. Thus it is possible to perform spreading resistance measurements and four-point probe measurements along one and the same measuring track and in this manner at the same time to vary the local resolution. A comparison of both measurement results will in particular yield information on the conditions of the resistivity in axial direction of the slice. Essential prerequisites for an absolute measurement are fulfilled with the aluminum-silicon contact. However, the investigations made up to now show that the resistivity calculated from the spreading resistance is smaller than the one obtained with the four-point probe measurement by approximately a factor of 0.8.
On the Calibration and Performance of a Spreading Resistance Probe
Authors: Ruiz H. J. , Voltmer F. W.
Published: August 2009

In this paper, techniques are presented for material standards selection for calibration purposes, materials and calibration block preparation, and techniques for data collection and processing for the spreading resistance probe. A description of the variation with time of the calibration of a spreading resistance probe is presented. Problems encountered with characterization of high resistivity p-type silicon are discussed, and examples of the probe performance in the characterization of germanium are also presented.
Preparation of a Lightly Loaded, Close-Spaced Spreading Resistance Probe and its Application to the Measurement of Doping Profiles in Silicon
Authors: Deines J. L. , Gorey E. F. , Michel A. E. , Poponiak M. R.
Published: August 2009

A commercially available spreading resistance probe, the ASR-100, was modified to operate with lighter probe loading and smaller probe spacing. The advantages of device structure profiling, increased resolution, and reduction in the “correction factor” in the converted impurity concentration profile are realizable with smaller probe spacing. The effect of the probe modifications on sample profiles and profile quality is discussed for thin epitaxial layers, bipolar transistor structures, and ion-implanted layers. Sample preparation, as influenced by the beveling technique, is also shown to have an effect on profile quality. A novel method for precise measurement of very small bevel angles is described.
The Evaluation of Thin Silicon Layers by Spreading Resistance Measurements
Authors: Gruber Gilbert A. , Pfeifer Robert F.
Published: August 2009

The spreading resistance measurement technique is the only one capable of providing precise thickness measurements and detailed concentration profiles on any type of active device layer or structure formed in silicon on a routine basis. The methods employed in the evaluation of thin layer structures of the type used for microwave devices is discussed and the application of these methods to thin NN+, P+NN+ and P+N silicon structures formed by combinations of diffusion, epitaxy and ion implantation is illustrated.
Evaluation of the Effective Epilayer Thickness by Spreading Resistance Measurement
Authors: Murrmann H. , Sedlak F.
Published: August 2009

Two types of double layer structure which are dealt with in the multi layer theory have been examined: 1. a top layer is insulated against a bottom layer (i.e. pn-junction, R(∞)). 2. a top layer is shorted by a bottom layer (i.e. n+-buried layer, R(0)). In both arrangements the Spreading Resistance depends strongly on layer thickness d and on the radius a of contact area. Knowing the effective radius the epilayer thickness can easily be evaluated from Spreading Resistance Measurement and making use of the function R(∞)R(0)=f(da). This method is nondestructive and less rime consuming than other common methods. A simple test pattern is proposed for evaluating the thickness on wafers in process. A comparison between this method and an IR-reflexion method (Digilab FTG 12) showed that both are in very good agreement in thickness range of 2.....6μm.
Application of the Spreading Resistance Technique to Silicon Characterization for Process and Device Modeling
Authors: Schroen Walter H.
Published: August 2009

In recent years, the interest in modeling of semiconductor processes and silicon device parameters has intensified considerably. Precise knowledge of the doping distribution in the semiconductor emerged as a key requirement for input and starting condition of many of these models and for their verification. It turned out that the spreading resistance technique, after careful probe calibration and multilayer data analysis, is able to supply some of the required data better than any other characterization technique available. This paper discusses these successful applications. On the other hand, this paper points out inherent limitations of the spreading resistance technique with regard to resolution and precision, and how this affects the verification of process and device models. Finally, the paper describes ways to supplement the spreading resistance technique by other material characterization or electrical techniques so that the combination of these methods is capable of generating the required experimental data for the analytical models.
Introduction
Authors: Barkman E. F.
Published: August 2009

For the past several years, ASTM Committee E-12 on Appearance of Materials has been studying the appearance of metallic surfaces. This work has been conducted by Task Group 4. The participants in this work soon realized that there existed no adequate and comprehensive compilation of techniques for describing the appearance attributes of metallic surfaces. Other materials have long been studied with respect to their appearance. For example, the color, texture, and visual appearance of white and colored textiles, papers, and paints have been well defined, and ASTM test methods for measuring chromatic attributes and gloss can be found in the Book of Standards. The metallic surfaces, however, presented a uniquely different problem of measuring the appearance. Most metallic surfaces have very little or no chromatic attributes. Or at least the chromatic features are not of major importance to describe the visual properties of metals. Instead, metals exhibit the features which the consumer generally refers to as “brightness.” This term, which is somewhat of a misnomer for describing what the eye first notices about metals, is one of the problems of accurate definitions confronting the workers in this field. In the past several years the metallic appearance of bare and coated metal products has developed an increasingly larger importance to consumer products such as automotive and appliances. Other product areas, such as jewelry and other decorative items, are examples where the metallic appearance is a primary characteristic of consumer appeal of the product. The space age also introduced needs for measuring and defining the optical properties of metallic surfaces as related to reflectors, surfaces to provide thermal balance in space vehicles, and the characteristics of metallic surfaces with respect to electromagnetic radiation and reflection outside the visible spectrum. This publication, however, will present results and findings of workers who are primarily concerned with the materials most commonly used for consumer products such as aluminum and stainless steel. It should be emphasized, however, that the discussions on the appearance and measurement of metallic surfaces, though giving heavy emphasis to aluminum and stainless steel can be applied usually to other metals such as plated coatings (whether on metal or plastic substrates) including chromium, nickel, and silver, and any other metal surface where it is desirable to describe the metallic appearance.
Appearance Attributes of Metallic Surfaces
Authors: Hunter R. S.
Published: August 2009

The appearance of bare and finished metal surfaces is becoming more important, especially to the automotive and architectural fields. The metals industry, however, is behind the paint, plastics, and paper industries in the development of methods for instrumental appearance measurements of metal products. Metals are optically different from nonmetals because of free electron movement, and thus nonmetal measurement techniques are not generally applicable. A complete analysis of metallic appearance requires complex combinations of spectrophotometric and goniophotometric curves. By isolating attributes which can be related directly to observed appearance and correlated with physical properties, simpler instrumental measurement techniques can be developed. These attributes can be divided arbitrarily into color and geometric attributes. As described in this paper, the color attributes of metallic appearance are shininess, hue, and saturation. The geometric attributes are haze, distinctness of image, luster, surface texture, and directionality.
Measurement of Appearance Characteristics of Stainless Steel
Authors: Glubish A. E.
Published: August 2009

One of the primary reasons for the selection of stainless steel for architectural and automotive uses is its inherent ability to retain its original beauty for long periods of time. Appearance, therefore, is important for matching the alloy or finish to a particular application. The physical characteristics that affect the appearance of a metal surface include many factors such as color, gloss, haze, texture, directionality, shape, and several others not yet categorized. Present day visual methods consider all of these factors simultaneously but are incapable of determining which attribute is the most influential to a particular appearance. This paper describes instrumental methods now available in the laboratory to measure some of the attributes mentioned above but which are not used widely to measure and control appearance during production. This paper consists of color, gloss, haze, and directionality data, and pictorial views of three bright and three diffuse stainless steel finishes selected to best show the surface variations usually obtained. High magnification electron micrographs of each surface are included also. The paper shows that there are certain measurements and photographic techniques that can be useful for evaluating the appearance of ferritic and austenitic steel surfaces if they are applied carefully.
Instruments for the Measurement of Metallic Appearance
Authors: Christie J. S.
Published: August 2009

The need to measure and control the appearance of metallic surfaces is increasing. Because metals are optically different from nonmetals, methods of appearance control can not be borrowed directly from other industries. Nevertheless, numerous instruments for measuring the color and geometric attributes of metallic appearance have been developed. Methods and terminology are reviewed, and instruments currently available to the metals technologist are described.
Proposed Method of Measurement for Appearance of Rolled Aluminum Surfaces Using Distinctness of Image and Diffuse Reflectance Measuring Instruments
Authors: Robinson B. W.
Published: August 2009

1.1 This method provides values for four independently variable surface characteristics that can be used to describe precisely the appearance of rolled aluminum surfaces. This method is applicable to finishes ranging from mill sheet to luster sheet, from utility foil to decorative foil, as well as bright anodized surfaces. 1.2 Color is not included as an appearance characteristic, nor are random surface defects identified using this method.
Bibliographical Abstracts of Methods for Analysis of Synthetic Detergents
Authors: Bernstein Rubin ,   Committee D-12, Subcommittee T-2
Published: August 2009

The growth of the synthetic detergent Industry has accelerated in recent years, resulting in an increase in the number of different types of detergents as well as in their complexity. The literature on detergent analysis has also grown to a point where a bibliography of published methods should prove useful to persons engaged in the manufacture, analysis, development, and evaluation of surfactants. Accordingly, this bibliography has been prepared by Rubin Bernstein with the cooperation of a number of Subcommittee T-2 members who supplied much of the data. The style of this bibliography follows closely that of “Metal Cleaning Bibliographical Abstracts.” The references, which are numbered consecutively, are listed by year and then by author or by the journal in which the article appeared if anonymous. A number of the abstracts are based on the original article. However, many are re-abstracts from “Chemical Abstracts.” It is hoped to keep these abstracts current. Interested readers are therefore urged to advise the author of any corrections or additions to be made.
Transition Behavior in V-Notch Charpy Slow-Bend Tests
Authors: Hartbower Carl E.
Published: August 2009

V-notch Charpy slow-bend tests (see also Armstrong (1)) have been conducted over a range of temperatures, using three commercial structural steels representing the full range of commercial deoxidation practice, and a number of carbon-manganese steels containing 0.04 to 0.45 per cent carbon and 0.43 to 1.05 per cent manganese. The criteria used in evaluating slow-bend performance were (1) lateral expansion, (2) fracture appearance, and (3) temperature. In particular, attention was focused on the deformation, fibrosity, and temperature attending catastrophic crack propagation (sudden and complete fracture of the test specimen at maximum load). It was found that considerable plastic deformation occurs in the V-notch Charpy slow-bend bar even at temperatures resulting in 90 per cent crystallinity and catastrophic crack-propagation. By defining transition temperature as the highest temperature at which an initiating crack can propagate under action of the elastic-stress energy alone, that is, sudden and complete fracture of the test specimen at maximum load, and by noting the deformation occurring in specimens which fractured at maximum load, it was possible to differentiate between the deformation attending the crack initiation and crack propagation stages of fracture in slow bend.
Effects of Manganese and Aluminum Contents on Transition Temperature of Normalized Nickel Steel
Authors: Armstrong T. N. , Miller O. O.
Published: August 2009

It has been fairly well established that fine ferrite grain size is conducive to low temperature of transition from ductile to brittle behavior in normalized carbon steels of moderate to low carbon content (1).2 The generally accepted practice for producing fine grained steels is to add aluminum to the melt after preliminary deoxidation with silicon. Although the amount of the addition will depend upon the condition of the melt, a residual or acid-soluble aluminum content of 0.015 per cent usually will ensure fine austenite grains at the temperatures associated with normalizing and fine ferrite grains after air cooling (2, 3). There has been recurring evidence, however, that the effect of aluminum on transition temperature may be more extensive than that of grain refinement alone (4); consequently, the minimum aluminum content required to obtain fine grain size might not necessarily be the optimum quantity to produce the lowest transition temperature. The transition temperature of mild carbon steel also may be lowered by increasing the manganese content (5, 6), and the addition of nickel long has been recognized as one of the most effective means of lowering the temperature of embrittlement (7). What has not been determined is whether the effects of manganese and nickel are additive and whether the optimum aluminum content for lowering the transition temperature of carbon steels is independent of the manganese content and whether the optimum aluminum addition is the same for nickel steel as for carbon steel. The plan evolved to study the effect of nickel, manganese, and aluminum on transition temperature called for 24 heats, half of which contained no nickel and the other half 21/4 per cent nickel, with each type at three manganese levels of 0.4, 0.95, and 1.5 per cent, and each of these six combinations at the four levels of acid-soluble aluminum of nil to 0.005, 0.030, 0.055 and 0.090 per cent. Carbon level of all melts was maintained at 0.15 ± 0.01 per cent. This block-type design improves validity on the effects of nickel, manganese, and aluminum because it provides data on the effect of each one at all combinations of the others and permits easy comparison when the results are presented graphically. This design has the additional advantage that the data can be analyzed statistically by the powerful “analysis of variance” technique (8) to indicate the degree of certainty of the conclusions, provided, of course, that no large uncontrolled variables are involved. Unfortunately, normalizing produced a significant quantity of martensite in four heats, and the aimed-for deoxidation practice was not quite achieved in one heat. These relatively large uncontrolled variables made it impossible to apply successfully the analysis of variance; however, several simpler statistical tests were applied to the data, as shown later in the paper.
Automatic Impact Testing from Room Temperature to −236 C
Authors: DeSisto Thomas S.
Published: August 2009

Using liquid nitrogen and liquid helium as coolants, Charpy V-notch impact tests were conducted from room temperature to −236 C in an automatic device, which houses within a vacuum a complete impact machine and storage space for 105 specimens. Comparison impact tests of AISI 4340 steel conducted on both a conventional and the low-temperature impact machine to −195.8 C show that the device is a useful and accurate impact tool.
The Influence of Pendulum Flexibilities on Impact Energy Measurements
Authors: Bluhm Joseph I.
Published: August 2009

It is hypothesized that the flexibilities of impact machines give rise to a potentially significant error in the usual impact test. An overly simplified and idealized model of an impact machine is analyzed in some detail. In particular, the relation between the stiffness of the machine, the effective stiffness of the specimen, and the maximum load developed is explored.
Longitudinal Impact Tests of Long Bars with a Slingshot Machine
Authors: Ramberg W. , Irwin L. K.
Published: August 2009

The history of the longitudinal impact test from Thomas Young (1807) to the present is reviewed briefly to show its importance for a study of the dynamic strength of materials and to bring out some of the difficulties in the interpretation of the results of impact tests. These difficulties call for further tests under controlled conditions. A slingshot machine for making impact tests at the National Bureau of Standards is described, and results obtained from these tests on bars of steel and of copper are given. These show that the strain pulses were attenuated in the steel with much less change in shape than that represented by the simple von Kármán theory of plastic strain waves. The high-strength steel exhibited a time delay between the sudden application of a high stress and the initiation of yielding, which decreased with increasing stress in accord with the dislocation locking theory of Cottrell as developed by Yokobori. The need for further work in this field is emphasized.
Shock Tester for Shipping Containers
Authors: Cross W. H. , McWhirter Max
Published: August 2009

The object of this investigation was to develop a method of testing shipping containers for the longitudinal shocks encountered during railroad switching operations. Field data were gathered by measurement of accelerations encountered on a railroad car during various controlled switching conditions at speeds up to 10 mph. Shock spectra were prepared from the acceleration-time curves recorded. The test method employs an inclined ramp which supplies the energy for the system. The container to be tested is attached to a cart which is allowed to roll down the ramp and strike a stack of rubber pads that are attached to a fixed bumper. The shock pulse wave form obtained is reproducible. The magnitude and duration of the shock pulse to be applied to a given container are governed by the dynamic response of an undamped simple single-degree-of-freedom system having a natural frequency equal to the resonant frequency of the container shock mitigating system. The response is obtained from the shock spectra which was prepared from field data. The ramp test fixture will simulate the longitudinal shocks, encountered during railroad switching, up to impact velocities of 8 mph for shock mitigating systems with resonant frequencies below 20 cps.