Skip Nav Destination
Close Modal
Search Results for
digital measurements
Update search
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
Filter
- Title
- Authors
- Author Affiliations
- Full Text
- Abstract
- Keywords
- DOI
- ISBN
- EISBN
- Issue
- ISSN
- EISSN
- Volume
- References
NARROW
Format
Topics
Book Series
Date
Availability
1-20 of 446 Search Results for
digital measurements
Follow your search
Access your saved searches in your account
Would you like to receive an alert when new items match your search?
Sort by
Series: ASM Handbook
Volume: 9
Publisher: ASM International
Published: 01 December 2004
DOI: 10.31399/asm.hb.v09.a0003758
EISBN: 978-1-62708-177-1
.... The article concentrates on the basic properties of digital measurements that are the core of quantitative image analysis. It provides a brief description of the specimen and apparatus preparation as well as the image acquisition. The article explains how to evaluate stereological parameters and provides...
Abstract
This article reviews the essential parts of the complex process of quantitative image analysis to assist automatic image analysis in laboratories. It describes the basic difference between the bias of classical manual stereological analysis and quantitative image analysis. The article concentrates on the basic properties of digital measurements that are the core of quantitative image analysis. It provides a brief description of the specimen and apparatus preparation as well as the image acquisition. The article explains how to evaluate stereological parameters and provides the general rules and guidelines for optimization of image processing algorithms from the viewpoint of shape quantification. It concludes with examples that demonstrate the usefulness of automatic image analysis in comparison to manual methods.
Series: ASM Handbook
Volume: 4B
Publisher: ASM International
Published: 30 September 2014
DOI: 10.31399/asm.hb.v04b.a0005925
EISBN: 978-1-62708-166-5
.... The reduced cost and more compact packaging of digital support hardware has spawned the integration of temperature control with auxiliary functions such as process documentation and workpiece flow. These process management systems ( Fig. 4 ) can integrate the functions of temperature measurement, loop control...
Abstract
Temperature control in heat treating is of paramount importance in maintaining the quality and achieving the desired metallurgical results. This article provides a detailed account of the factors affecting temperature control in heat treating furnaces, with information on temperature control systems, including contact sensors, noncontact sensors, controllers, energy-flow regulators, measurement instruments, and set-point programmers. Common contact sensors include temperature scales, thermocouples, and resistance temperature detectors, whereas optical pyrometers and on-line radiation thermometers fall under the noncontact type. The article describes two types of instrumentation used in heat treating: field test instruments for temperature-uniformity surveys and system-accuracy tests; and controlling, monitoring, and recording instruments for digital instrumentation.
Series: ASM Handbook Archive
Volume: 10
Publisher: ASM International
Published: 01 January 1986
DOI: 10.31399/asm.hb.v10.a0001768
EISBN: 978-1-62708-178-8
... by the cesium (10 wt%) map (f), and perovskite by the strontium (2 wt%) map (g). Fig. 13 Digital composition map of a zinc-containing copper specimen. (a) Digital compositional map of a portion of the grain boundary shown in Fig. 11 . Note the continuous gray scale presentation. The gray scale...
Abstract
Electron probe microanalysis (EPMA) makes it possible to combine structural and compositional analysis in one operation. This article describes the basic concepts of microanalysis and the processing of EPMA that involves the measurement of the characteristic X-rays emitted from a microscopic part of a solid specimen bombarded by a beam of accelerated electrons. It provides information on the various aspects of energy-dispersive spectrometry (EDS) and wavelength-dispersive spectrometry (WDS), and elucidates the qualitative analysis of the major constituents of EDS and WDS. The article includes information on the analog and digital compositional mapping of elemental distribution, and describes the strengths and weaknesses of WDS and EDS spectrometers in X-ray mapping. It also outlines the application of EPMA for solving various problems in materials science.
Series: ASM Handbook
Volume: 9
Publisher: ASM International
Published: 01 December 2004
DOI: 10.31399/asm.hb.v09.a0003757
EISBN: 978-1-62708-177-1
... is measured both intensively (for example, number of pixels per unit distance) and extensively (for example, total number of pixels on each axis of the image), depending on the digitization method. Typical values for a scanner range from 300 dpi (dots per inch) to several thousand dpi, while modern digital...
Abstract
This article reviews the main theoretical and practical aspects of sequence normally followed in digital image-acquisition, processing, analysis, and output for material characterization. It discusses the main methods of digital imaging, image processing, and analysis, as applied to microscopy of materials. The article describes the basic concepts of sampling and resolution and quantization of light microscopy, scanning electron microscopy, and transmission electron microscopy. It discusses the acquisition of a digital image that accurately represents the sample under observation and output of the image to a printer. The methods used to enhance the digital image and to extract quantitative information are also described. Different types of image segmentation, namely, adaptive segmentation and contour-based segmentation, are reviewed. The article also presents case studies on the application of image processing and analysis to materials characterization.
Series: ASM Handbook
Volume: 4B
Publisher: ASM International
Published: 30 September 2014
DOI: 10.31399/asm.hb.v04b.a0005931
EISBN: 978-1-62708-166-5
... treating industry. With this type of meter, it is important to keep the damping oil inside the sight glass clean (by means of regularly changing the oil), because dirty oil will transmit less light, which will bias the output of the digital measurement. More recently, new sensing technologies have...
Abstract
Heat treating furnaces require different control systems and integration for achieving optimum technical results and enabling safe operation. This article focuses on atmosphere furnaces, with some coverage on controls for vacuum furnaces. Heat treating operations require reliable monitoring and control of motion and position of various mechanical components with the help of mechanical limit switches, proximity sensors, and distance- and position-measuring devices. Using inputs from both flow meters and sensors, such as thermocouples and oxygen sensors, flow measurement control systems must be able to adjust the flow of gases for process optimization. The operator interface of a furnace-control system displays critical information such as the furnace temperature, atmosphere status, alarms, electronic chart recorders, recipe, and maintenance. A supervisory control and data-acquisition (SCADA) system is used to monitor, collect, and store data from multiple pieces of equipment.
Series: ASM Handbook
Volume: 1A
Publisher: ASM International
Published: 31 August 2017
DOI: 10.31399/asm.hb.v01a.a0006336
EISBN: 978-1-62708-179-5
...) or coordinate-measuring arms (CMAs) convert measurements of a surface to digital data that can be analyzed by software. These devices can range from manually operated to fully automated devices that perform computer-aided-design-based inspections. The CMMs are highly precise and accurate, require less labor...
Abstract
Nondestructive inspection (NDI) methods for cast iron are used to ensure that the parts supplied perform as required by the purchaser. This article focuses on the principal nondestructive methods used to inspect for anomalies in cast irons and to determine if the volume, shape, size, or number of these anomalies exceeds the maximum allowed by the purchaser. The nondestructive methods include visual inspection, dimensional inspection, liquid penetrant inspection, magnetic-particle inspection, eddy-current inspection, radiographic inspection, ultrasonic inspection, resonant testing, and leak testing. The technique, strengths, and weaknesses of each of the nondestructive methods are also discussed.
Series: ASM Handbook
Volume: 17
Publisher: ASM International
Published: 01 August 2018
DOI: 10.31399/asm.hb.v17.a0006469
EISBN: 978-1-62708-190-0
.... There also are now a range of handheld, mostly digital, ultrasonic thickness gages that, when calibrated, typically give a digital readout of part thickness and will record and store (and transfer) some number of measurements. In addition to conventional single-transducer pulse-echo inspection...
Abstract
This article considers the two primary methods used for ultrasonic inspection: pulse-echo and the transmission methods. Pulse-echo inspection can be accomplished with longitudinal, shear, surface (Rayleigh), or Lamb (plate) waves using a diverse range of transducers. The article discusses the principles of each of these inspection methods. It describes the applications and the basic data formats for single-element transducer-based systems, including A-scans, B-scans, and C-scans. The article provides information on electronic equipment used for ultrasonic inspection. It also describes how specific material conditions produce and modify A-scan indications. The article provides information on the controls and their functions for the display unit of the electronic equipment. It describes the techniques used for the identification and characterization of flaws, namely, surface (Rayleigh) wave and ultrasonic polar scan techniques.
Series: ASM Handbook
Volume: 17
Publisher: ASM International
Published: 01 August 2018
DOI: 10.31399/asm.hb.v17.a0006439
EISBN: 978-1-62708-190-0
...Abstract Abstract Machine vision, also referred to as computer vision or intelligent vision, is a means of simulating the image recognition and analysis capabilities of the human eye and brain system with digital techniques. The machine vision functionality is extremely useful in inspection...
Abstract
Machine vision, also referred to as computer vision or intelligent vision, is a means of simulating the image recognition and analysis capabilities of the human eye and brain system with digital techniques. The machine vision functionality is extremely useful in inspection, supervision, and quality control applications. This article presents a variety of machine vision functions for different purposes and provides a comparison of machine and human vision capabilities in a table. It discusses the processes of a machine vision system: image acquisition, image preprocessing, image analysis, and image interpretation. The article provides information on the uses of machine vision systems in three categories of manufacturing applications: visual inspection, identification of parts, and guidance and control applications.
Series: ASM Handbook
Volume: 17
Publisher: ASM International
Published: 01 August 2018
DOI: 10.31399/asm.hb.v17.a0006472
EISBN: 978-1-62708-190-0
... not exceed two cycles as measured to the 20 dB level below the peak response ( Ref 6 ). Instrumentation Choice of Digitizer Settings The recording equipment generally employs a digitizer that records amplitude data at regular intervals, for example, with a cycle time of 20 MHz. It is vital...
Abstract
Time-of-flight diffraction (TOFD) is an ultrasonic technique used to detect diffracted waves from crack tips and to size the cracks from the arrival times of those waves. This article discusses the basic considerations and provides information on probe selection, gain setting, and instrumentation of TOFD. It describes the numerous effects that result from modifying the probe characteristics. The article provides the American Society of Mechanical Engineers (ASME), the European Committee for Standardization (CEN), and the International Standardization Organization (ISO) recommendations for the reference blocks according to applicable codes and standards. It also provides the ASME, CEN, and ISO recommendations for examination of welds. The article concludes with information on the interpretation and analysis of TOFD images with an aid of sizing algorithms.
Series: ASM Handbook
Volume: 8
Publisher: ASM International
Published: 01 January 2000
DOI: 10.31399/asm.hb.v08.a0003275
EISBN: 978-1-62708-176-4
... is a hand-sized instrument that measures the indentation hardness of rubber and plastic products. It is manually applied to the test specimen, and the reading is observed on a dial or digital indicator. Laboratory accuracy can also be obtained by mounting the durometer on one of several types of operating...
Abstract
Miscellaneous hardness tests encompass a number of test methods that have been developed for specific applications. These include dynamic, or "rebound," hardness tests using a Leeb tester or a Scleroscope; static indentation tests on rubber or plastic products using the durometer or IRHD testers; scratch hardness tests; and ultrasonic microindentation testing. This article reviews the procedures, equipment, and applications associated with these alternate hardness test methods.
Series: ASM Handbook Archive
Volume: 11
Publisher: ASM International
Published: 01 January 2002
DOI: 10.31399/asm.hb.v11.a0003536
EISBN: 978-1-62708-180-1
... in the vertical sections. To calculate the roughness parameter R L , it is necessary to measure the total length of the fracture profile λ. Once the fracture profile is digitized, the total profile length λ is simply given by the sum of the lengths of the straight line segments joining the adjacent digitized...
Abstract
The quantitative characterization of fracture surface geometry, that is, quantitative fractography, can provide useful information regarding the microstructural features and failure mechanisms that govern material fracture. This article is devoted to the fractographic techniques that are based on fracture profilometry. This is followed by a section describing the methods based on scanning electron microscope fractography. The article also addresses procedures for three-dimensional fracture surface reconstruction. In each case, sufficient methodological details, governing equations, and practical examples are provided.
Book: Surface Engineering
Series: ASM Handbook
Volume: 5
Publisher: ASM International
Published: 01 January 1994
DOI: 10.31399/asm.hb.v05.a0001237
EISBN: 978-1-62708-170-2
... metallography or stereology relates two-dimensional features, as seen on photographs or images, to the actual three-dimensional microstructure. Common measurements include grain size, inclusion rating, phase determination, and density of dislocations. E.E. Underwood has described the basic measurement...
Abstract
Quantitative image analysis has expanded the capabilities of surface analysis significantly with the use of computer technology. This article provides an overview of the quantitative image analysis and optical microscopy. It describes the various steps involved in surface preparation of samples prone to abrasion damage and artifacts for quantitative image analysis.
Series: ASM Handbook
Volume: 11B
Publisher: ASM International
Published: 15 May 2022
DOI: 10.31399/asm.hb.v11B.a0006851
EISBN: 978-1-62708-395-9
... of a professional digital camera. It covers basic photographic principles and manipulation of settings that assist in producing high-quality images. The need for accurate photographic documentation in failure analysis is also presented. failure analysis photographic documentation photography professional...
Abstract
Failure analysis is an investigative process in which the visual observations of features present on a failed component and the surrounding environment are essential in determining the root cause of a failure. This article reviews the basic photographic principles and techniques that are applied to failure analysis, both in the field and in the laboratory. It discusses the processes involved in visual examination, field photographic documentation, and laboratory photographic documentation of failed components. The article describes the operating principles of each part of a professional digital camera. It covers basic photographic principles and manipulation of settings that assist in producing high-quality images. The need for accurate photographic documentation in failure analysis is also presented.
Book Chapter
Series: ASM Desk Editions
Publisher: ASM International
Published: 01 December 1998
DOI: 10.31399/asm.hb.mhde2.a0003238
EISBN: 978-1-62708-199-3
... inspection involves viewing of a real-time image on a fluorescent screen or image-intensifier, the radiographic process is termed “real-time inspection.” When electronic, nonimaging instruments are used to measure the intensity of radiation, the process is termed “radiation gaging.” Tomography, a radiation...
Abstract
Radiography is a nondestructive-inspection method that is based on the differential absorption of penetrating radiation by the part or test piece (object) being inspected. This article discusses the fundamentals and general applications of radiography, and describes the sources of radiation in radiographic inspection, including X-rays and gamma rays. It deals with the characteristics that differentiate neutron radiography from X-ray or gamma-ray radiography. The geometric principles of shadow formation, image conversion, variation of attenuation with test-piece thickness, and many other factors that govern the exposure and processing of a neutron radiograph are similar to those for radiography using X-rays or gamma rays.
Series: ASM Handbook
Volume: 17
Publisher: ASM International
Published: 01 August 2018
DOI: 10.31399/asm.hb.v17.a0006456
EISBN: 978-1-62708-190-0
.... It also provides information on digital radiography, image processing and analysis, dual-energy imaging, and partial angle imaging, of a CT system. computed tomography digital radiography dual-energy imaging film radiography partial angle imaging real-time radiography X-ray computed tomography...
Abstract
Computed tomography (CT) is an imaging technique that generates a three-dimensional (3-D) volumetric image of a test piece. This article illustrates the basic principles of CT and provides information on the types, applications, and capabilities of CT systems. A comparison of performance characteristics for film radiography, real-time radiography, and X-ray computed tomography is presented in a table. A functional block diagram of a typical computed tomography system is provided. The article discusses CT scanning geometry that is used to acquire the necessary transmission data. It also provides information on digital radiography, image processing and analysis, dual-energy imaging, and partial angle imaging, of a CT system.
Series: ASM Handbook
Volume: 14B
Publisher: ASM International
Published: 01 January 2006
DOI: 10.31399/asm.hb.v14b.a0005153
EISBN: 978-1-62708-186-3
..., the hydraulic ram of a stamping press is an actuator, with hydraulic pressure as its input and punch force as its output, while the metal that is formed is the plant, with punch force as an input and a material deformation measure such as thickness as an output. Systems may have several inputs and outputs...
Abstract
The use of an effective control design, along with high-performance hardware and software for controller implementation, allows the use of feedback process control for manufacturing processes to improve part quality and consistency. This article provides an overview of control system design and its application to various manufacturing processes. It presents various examples of control system applications to show that appropriate control strategies increase the robustness of the processes by eliminating process sensitivity to system variations and external disturbances.
Series: ASM Handbook
Volume: 17
Publisher: ASM International
Published: 01 August 2018
DOI: 10.31399/asm.hb.v17.a0006445
EISBN: 978-1-62708-190-0
... Direct-Current Resistivity Testing A voltage field within a conductive solid will create currents that are influenced by structural irregularities, including cracks and porosity. This characteristic has been used to measure carburized case depth in wrought steels ( Ref 4 , 5 ). The arrangement...
Abstract
The potential for introducing defects during processing becomes greater as the relative density of pressed and sintered powder metallurgy (PM) parts increases and more multilevel parts with complex geometric shapes are produced. This article discusses the potential defects in pressed and sintered PM parts: density variations, compaction and ejection cracks, microlaminations, poor degree of sintering, and voids from prior lubricant agglomerates. It describes the various methods applicable to green compacts: direct-current resistivity testing, radiographic techniques, computed tomography, and gamma-ray density determination. The article also discusses the methods for automated nondestructive testing of pressed and sintered PM parts: acoustic methods-resonance testing, eddy current testing, magnetic bridge comparator testing, ultrasonic techniques, radiographic techniques, gamma-ray density determination, and visual inspection.
Series: ASM Handbook
Volume: 17
Publisher: ASM International
Published: 01 August 2018
DOI: 10.31399/asm.hb.v17.a0006459
EISBN: 978-1-62708-190-0
...Abstract Abstract Digital radiography is a technique that uses digital detector arrays (linear or area) to capture an X-ray photonic signal and convert it to an electronic signal for display on a computer. This article begins with an overview of real-time radiography and provides a schematic...
Abstract
Digital radiography is a technique that uses digital detector arrays (linear or area) to capture an X-ray photonic signal and convert it to an electronic signal for display on a computer. This article begins with an overview of real-time radiography and provides a schematic illustration of a typical radioscopic system using an X-ray image intensifier. It discusses the advantages and limitations of real-time radiography. Computed radiography (CR) is one of the radiography techniques that utilizes a reusable detector comprised of photostimuable luminescence (PSL) storage phosphor. The article provides a schematic illustration of a typical storage phosphor imaging plate. It concludes with a discussion on the benefits of digital radiography.
Series: ASM Handbook
Volume: 9
Publisher: ASM International
Published: 01 December 2004
DOI: 10.31399/asm.hb.v09.a0003754
EISBN: 978-1-62708-177-1
... for measuring the distances in the x - and y -directions, and some offer digital readout of these data. The focusing controls may contain rulings for estimating vertical movement. Some units have motorized stages and focus controls that allow automated movement of the sample often controlled by a PC and image...
Abstract
This article provides information on the basic components of a light microscope, including the illumination system, collector lens, and optical and mechanical components. It describes optical performance in terms of image aberrations, resolution, and depth of field. The article discusses the examination of specimen surfaces using polarized light, phase contrast, oblique illumination, dark-field illumination, bright-field illumination, interference-contrast illumination, and phase contrast illumination. Special techniques and devices that may be used with the optical microscope, to obtain additional information, are also described. The article concludes with information on photomicroscopy and macrophotography.
Series: ASM Handbook
Volume: 8
Publisher: ASM International
Published: 01 January 2000
DOI: 10.31399/asm.hb.v08.a0003314
EISBN: 978-1-62708-176-4
...: axial fatigue testing machines and bending fatigue machines. Load cells, grips and alignment devices, extensometry and strain measuring devices, environmental chambers, graphic recorders, furnaces, and heating systems of ancillary equipment are discussed. The article presents technologies available...
Abstract
This article describes the phenomena of crack initiation and early growth. It examines specimen design and preparation as well as the apparatus used in crack initiation testing. The article provides descriptions of the various commercially available fatigue testing machines: axial fatigue testing machines and bending fatigue machines. Load cells, grips and alignment devices, extensometry and strain measuring devices, environmental chambers, graphic recorders, furnaces, and heating systems of ancillary equipment are discussed. The article presents technologies available to accomplish closed loop control of materials testing systems in performing standard materials tests and for the development of custom testing applications. It explores the advanced software tools for materials testing. The article includes a description of baseline isothermal fatigue testing, creep-fatigue interaction, and thermomechanical fatigue. The effects of various variables on fatigue resistance and guidelines for fatigue testing are also presented.