5.1 This test method provides information on the uniaxial tensile properties and tensile stress-strain response of a ceramic composite tube—tensile strength and strain, fracture strength and strain, proportional limit stress and strain, tensile elastic modulus, etc. The information may be used for material development, material comparison, quality assurance, characterization, and design data generation.5.2 Continuous fiber-reinforced ceramic composites (CFCCs) are composed of continuous ceramic-fiber directional (1D, 2D, and 3D) reinforcements in a fine-grain-sized (<50 µm) ceramic matrix with controlled porosity. Often these composites have an engineered thin (0.1 to 10 µm) interface coating on the fibers to produce crack deflection and fiber pull-out. These ceramic composites offer high-temperature stability, inherent damage tolerance, and high degrees of wear and corrosion resistance. As such, these ceramic composites are particularly suited for aerospace and high-temperature structural applications (1, 2).35.3 CFCC components have a distinctive and synergistic combination of material properties, interface coatings, porosity control, composite architecture (1D, 2D, and 3D), and geometric shape that are generally inseparable. Prediction of the mechanical performance of CFCC tubes (particularly with braid and 3D weave architectures) cannot be made by applying measured properties from flat CFCC plates to the design of tubes. Direct uniaxial tensile strength tests of CFCC tubes are needed to provide reliable information on the mechanical behavior and strength of tube geometries.5.4 CFCCs generally experience “graceful” fracture from a cumulative damage process, unlike monolithic advanced ceramics which fracture catastrophically from a single dominant flaw. The tensile behavior and strength of a CFCC are dependent on its inherent resistance to fracture, the presence of flaws, and any damage accumulation processes. These factors are affected by the composite material composition and variability in material and testing—components, reinforcement architecture and volume fraction, porosity content, matrix morphology, interface morphology, methods of material fabrication, test specimen preparation and conditioning, and surface condition.5.5 The results of tensile tests of test specimens fabricated to standardized dimensions from a particular material or selected portions of a part, or both, may not totally represent the strength and deformation properties of the entire, full-size end product or its in-service behavior in different environments.5.6 For quality control purposes, results derived from standardized tubular tensile test specimens may be considered indicative of the response of the material from which they were taken, given primary processing conditions and post-processing heat treatments.1.1 This test method determines the axial tensile strength and stress-strain response of continuous fiber-reinforced advanced ceramic composite tubes at ambient temperature under monotonic loading. This test method is specific to tube geometries, because fiber architecture and specimen geometry factors are often distinctly different in composite tubes, as compared to flat plates.1.2 In the test method a composite tube/cylinder with a defined gage section and a known wall thickness is fitted/bonded into a loading fixture. The test specimen/fixture assembly is mounted in the testing machine and monotonically loaded in uniaxial tension at ambient temperature while recording the tensile force and the strain in the gage section. The axial tensile strength and the fracture strength are determined from the maximum applied force and the fracture force. The strains, the proportional limit stress, and the tensile modulus of elasticity are determined from the stress-strain data.1.3 This test method applies primarily to advanced ceramic matrix composite tubes with continuous fiber reinforcement: unidirectional (1D, filament wound and tape lay-up), bidirectional (2D, fabric/tape lay-up and weave), and tridirectional (3D, braid and weave). These types of ceramic matrix composites are composed of a wide range of ceramic fibers (oxide, graphite, carbide, nitride, and other compositions) in a wide range of crystalline and amorphous ceramic matrix compositions (oxide, carbide, nitride, carbon, graphite, and other compositions).1.4 This test method does not directly address discontinuous fiber-reinforced, whisker-reinforced, or particulate-reinforced ceramics, although the test methods detailed here may be equally applicable to these composites.1.5 The test method describes a range of test specimen tube geometries based on past tensile testing of ceramic composite tubes. These geometries are applicable to tubes with outer diameters of 10 to 150 mm and wall thicknesses of 1 to 25 mm, where the ratio of the outer diameter-to-wall thickness (dO /t) is typically between 5 and 30.1.5.1 This test method is specific to ambient temperature testing. Elevated temperature testing requires high-temperature furnaces and heating devices with temperature control and measurement systems and temperature-capable grips and loading fixtures, which are not addressed in this test method.1.6 The test method addresses test equipment, gripping methods, testing modes, allowable bending stresses, interferences, tubular test specimen geometries, test specimen preparation, test procedures, data collection, calculation, reporting requirements, and precision/bias in the following sections.  Section 1Referenced Documents 2Terminology 3Summary of Test Method 4 5Interferences 6Apparatus 7Hazards 8Test Specimens 9Test Procedure 10Calculation of Results 11Report 12Precision and Bias 13Keywords 14Annexes  Interferences Annex A1Test Specimen Geometry Annex A2Grip Fixtures and Load Train Couplers Annex A3Allowable Bending and Load Train Alignment Annex A4Test Modes and Rates Annex A51.7 Units—The values stated in SI units are to be regarded as standard.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in Section 8.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Hexavalent chromium is anthropogenic from a number of commercial and industrial sources. It readily penetrates biological membranes and has been identified as a carcinogen and industrial toxin. Hexavalent chromium is a known inhalation irritant and is associated with respiratory cancer (5).5.2 Ambient atmospheric concentrations of hexavalent chromium are well below the detection limits of previous analytical methods utilized for the determination of hexavalent chromium (2).5.3 Ambient atmospheric concentrations of hexavalent chromium provide a means of evaluating exposures in a manner that can be related to health-based risk levels. The data for samples collected in situ provide an improved basis for health assessments of potential exposures (5).5.4 This test method provides step-by-step instructions for the sampling and analysis of total suspended ambient air particulates for hexavalent chromium.5.5 This test method assumes that field and laboratory personnel are familiar with low volume ambient air sampling and hexavalent chromium analysis by ion chromatography with post-column derivatization. This method should not be performed for regulatory or compliance purposes until the field and laboratory personnel have demonstrated the ability to collect and analyze samples in such a manner as to pass the quality control requirements found in Section 13.1.1 This test method specifies a procedure for the sampling and analysis of airborne particulate matter for hexavalent chromium in ambient air samples.1.2 This method is applicable to the determination of masses of 0.40 to 20.0 ng of hexavalent chromium per sample without dilution. Detection limits vary by instrumentation. Some laboratories may be able to achieve lower detection limits. The lower limit of applicability for this method was determined in a 2019 multi-laboratory detection limit study (1).21.3 This method is applicable to hexavalent chromium measurement in the atmosphere from 0.019 to 0.926 ng/m3 assuming a 21.6 m3 sample volume. The lower range may be decreased with longer sampling times. The upper range can be increased using appropriate dilutions.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This practice establishes standardized tests for the performance evaluation of sensor-based continuous instruments for ambient air quality measurements. Public and private air monitoring interests have manifested themselves as a driving force for the deployment of air quality sensors and instruments to quantify air pollutant concentrations in communities, around schools, around industrial facilities, and elsewhere. Users of air quality sensors require information on the performance and limitations of these devices so that informed decisions regarding their suitability for various purposes can be determined. This practice describes both laboratory and field tests that provide information on candidate instrument repeatability, sensitivity, linearity, cross-interferences, drift and comparability with more costly instruments typically used by entities such as government agencies. The air quality sensors are first evaluated in a laboratory chamber by comparing their response to a reference instrument and challenging the gas sensors with interferents. The sensors are then deployed outdoors for field testing at two sites with different climates against reference air quality instruments. This practice is intended to be referenced in standards and codes that establish minimum performance quality for sensor-based ambient outdoor air monitoring.5.2 This practice is intended for air quality sensors that measure one or more of the criteria pollutants in ambient air (ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, PM10 and PM2.5) that can be operated in outdoor environments and can log a concentration reading. It is not intended for devices or transducers that require additional enclosures for deployment outdoors or post-processing to convert their output signal into a pollutant concentration reading.5.3 It is anticipated that the main users of this practice will be manufacturers, developers, and distributors of outdoor air quality sensors, air quality agencies, and environmental consultants.1.1 This practice establishes standardized tests for the performance evaluation of sensor-based continuous instruments for ambient outdoor air quality measurements. It describes both laboratory and field tests that provide information on candidate sensor repeatability, sensitivity, linearity, cross-interferences, drift, and comparability against reference instruments.1.2 This practice does not apply to sensors or instruments that remotely measure atmospheric pollutants using open path, lidar, or imaging technology.1.3 The evaluation procedures contained in this practice are for sensors that alone or in combination measure outdoor criteria pollutants in ambient air: particulate matter (PM2.5 and PM10), sulfur dioxide (SO2), ozone (O3), carbon monoxide (CO), or nitrogen dioxide (NO2) at concentrations that are relevant to public health.1.4 Testing is to be performed by a competent entity able to demonstrate that it operates in conformity with internationally accepted test laboratory quality standards such as ISO/IEC 17025.1.5 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Many regulators, industrial processes, and other stakeholders require determination of NMOC in atmospheres.5.2 Accurate measurements of ambient NMOC concentrations are critical in devising air pollution control strategies and in assessing control effectiveness because NMOCs are primary precursors of atmospheric ozone and other oxidants (7, 8).5.2.1 The NMOC concentrations typically found at urban sites may range up to 1 ppm C to 3 ppm C or higher. In order to determine transport of precursors into an area monitoring site, measurement of NMOC upwind of the site may be necessary. Rural NMOC concentrations originating from areas free from NMOC sources are likely to be less than a few tenths of 1 ppm C.5.3 Conventional test methods based upon gas chromatography and qualitative and quantitative species evaluation are relatively time consuming, sometimes difficult and expensive in staff time and resources, and are not needed when only a measurement of NMOC is desired. The test method described requires only a simple, cryogenic pre-concentration procedure followed by direct detection with an FID. This test method provides a sensitive and accurate measurement of ambient total NMOC concentrations where speciated data are not required. Typical uses of this standard test method are as follows.5.4 An application of the test method is the monitoring of the cleanliness of canisters.5.5 Another use of the test method is the screening of canister samples prior to analysis.5.6 Collection of ambient air samples in pressurized canisters provides the following advantages:5.6.1 Convenient collection of integrated ambient samples over a specific time period,5.6.2 Capability of remote sampling with subsequent central laboratory analysis,5.6.3 Ability to ship and store samples, if necessary,5.6.4 Unattended sample collection,5.6.5 Analysis of samples from multiple sites with one analytical system,5.6.6 Collection of replicate samples for assessment of measurement precision, and5.6.7 Specific hydrocarbon analysis can be performed with the same sample system.1.1 This test method2 presents a procedure for sampling and determination of non-methane organic compounds (NMOC) in ambient, indoor, or workplace atmospheres.1.2 This test method describes the collection of integrated whole air samples in silanized or other passivated stainless steel canisters, and their subsequent laboratory analysis.1.2.1 This test method describes a procedure for sampling in canisters at final pressures above atmospheric pressure (pressurized sampling).1.3 This test method employs a cryogenic trapping procedure for concentration of the NMOC prior to analysis.1.4 This test method describes the determination of the NMOC by the flame ionization detection (FID), without the use of gas chromatographic columns and other procedures necessary for species separation.1.5 The range of this test method is from 20 ppb C to 10 000 ppb C (1, 2).31.6 This test method has a larger uncertainty for some halogenated or oxygenated hydrocarbons than for simple hydrocarbons or aromatic compounds. This is especially true if there are high concentrations of chlorocarbons or chlorofluorocarbons present.1.7 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 This practice may be used for material development, material comparison, quality assurance, characterization, reliability assessment, and design data generation.4.2 Continuous fiber-reinforced ceramic matrix composites are generally characterized by crystalline matrices and ceramic fiber reinforcements. These materials are candidate materials for structural applications requiring high degrees of wear and corrosion resistance, and high-temperature inherent damage tolerance (that is, toughness). In addition, continuous fiber-reinforced glass matrix composites are candidate materials for similar but possibly less demanding applications. Although flexural test methods are commonly used to evaluate the mechanical behavior of monolithic advanced ceramics, the nonuniform stress distribution in a flexural test specimen in addition to dissimilar mechanical behavior in tension and compression for CFCCs leads to ambiguity of interpretation of test results obtained in flexure for CFCCs. Uniaxially loaded tensile tests provide information on mechanical behavior for a uniformly stressed material.4.3 The cyclic fatigue behavior of CFCCs can have appreciable nonlinear effects (for example, sliding of fibers within the matrix) which may be related to the heat transfer of the specimen to the surroundings. Changes in test temperature, frequency, and heat removal can affect test results. It may be desirable to measure the effects of these variables to more closely simulate end-use conditions for some specific application.4.4 Cyclic fatigue by its nature is a probabilistic phenomenon as discussed in STP 91A (1) and STP 588 (2).4 In addition, the strengths of the brittle matrices and fibers of CFCCs are probabilistic in nature. Therefore, a sufficient number of test specimens at each testing condition is required for statistical analysis and design, with guidelines for sufficient numbers provided in STP 91A (1), STP 588 (2), and Practice E739. Studies to determine the influence of test specimen volume or surface area on cyclic fatigue strength distributions for CFCCs have not been completed. The many different tensile test specimen geometries available for cyclic fatigue testing may result in variations in the measured cyclic fatigue behavior of a particular material due to differences in the volume of material in the gage section of the test specimens.4.5 Tensile cyclic fatigue tests provide information on the material response under fluctuating uniaxial tensile stresses. Uniform stress states are required to effectively evaluate any nonlinear stress-strain behavior which may develop as the result of cumulative damage processes (for example, matrix microcracking, fiber/matrix debonding, delamination, cyclic fatigue crack growth, etc.)4.6 Cumulative damage due to cyclic fatigue may be influenced by testing mode, testing rate (related to frequency), differences between maximum and minimum force (R or Α), effects of processing or combinations of constituent materials, environmental influences (including test environment and pre-test conditioning), or combinations thereof. Some of these effects may be consequences of stress corrosion or subcritical (slow) crack growth which can be difficult to quantify. Other factors which may influence cyclic fatigue behavior are: matrix or fiber material, void or porosity content, methods of test specimen preparation or fabrication, volume percent of the reinforcement, orientation and stacking of the reinforcement, test specimen conditioning, test environment, force or strain limits during cycling, wave shapes (that is, sinusoidal, trapezoidal, etc.), and failure mode of the CFCC.4.7 The results of cyclic fatigue tests of test specimens fabricated to standardized dimensions from a particular material or selected portions of a part, or both, may not totally represent the cyclic fatigue behavior of the entire, full-size end product or its in-service behavior in different environments.4.8 However, for quality control purposes, results derived from standardized tensile test specimens may be considered indicative of the response of the material from which they were taken for given primary processing conditions and post-processing heat treatments.4.9 The cyclic fatigue behavior of a CFCC is dependent on its inherent resistance to fracture, the presence of flaws, or damage accumulation processes, or both. There can be significant damage in the CFCC test specimen without any visual evidence such as the occurrence of a macroscopic crack. This can result in a loss of stiffness and retained strength. Depending on the purpose for which the test is being conducted, rather than final fracture, a specific loss in stiffness or retained strength may constitute failure. In cases where fracture occurs, analysis of fracture surfaces and fractography, though beyond the scope of this practice, is recommended.1.1 This practice covers the determination of constant-amplitude, axial tension-tension cyclic fatigue behavior and performance of continuous fiber-reinforced advanced ceramic composites (CFCCs) at ambient temperatures. This practice builds on experience and existing standards in tensile testing CFCCs at ambient temperatures and addresses various suggested test specimen geometries, specimen fabrication methods, testing modes (force, displacement, or strain control), testing rates and frequencies, allowable bending, and procedures for data collection and reporting. This practice does not apply to axial cyclic fatigue tests of components or parts (that is, machine elements with nonuniform or multiaxial stress states).1.2 This practice applies primarily to advanced ceramic matrix composites with continuous fiber reinforcement: uni-directional (1-D), bi-directional (2-D), and tri-directional (3-D) or other multi-directional reinforcements. In addition, this practice may also be used with glass (amorphous) matrix composites with 1-D, 2-D, 3-D, and other multi-directional continuous fiber reinforcements. This practice does not directly address discontinuous fiber-reinforced, whisker-reinforced or particulate-reinforced ceramics, although the methods detailed here may be equally applicable to these composites.1.3 The values stated in SI units are to be regarded as the standard and are in accordance with IEEE/ASTM SI 10.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Refer to Section 7 for specific precautions.

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5.1 This test method is applicable to the measurement of airborne carbon nanotubes in a wide range of ambient air situations and for evaluation of any atmosphere for carbon nanotube structures. Single carbon nanotube structures in ambient atmospheres have diameters below the resolution limit of the light microscope. This test method is based on transmission electron microscopy, which has adequate resolution to allow detection of small thin single carbon nanotubes and is currently a reliable technique capable of unequivocal identification of the majority of nanotube structures. Carbon nanotubes are often found, not as single carbon nanotubes, but as very complex, aggregated structures, which may or may not be aggregated with other particles.5.2 This test method applies to the analysis of a single filter and describes the precision attributable to measurements for a single filter. Multiple air samples are usually necessary to characterize airborne nanotube structure concentrations across time and space. The number of samples necessary for this purpose is proportional to the variation in measurement across samples, which may be greater than the variation in measurement for a single sample.1.1 This test method is an analytical procedure using transmission electron microscopy (TEM) for the determination of the concentration of carbon nanotubes and carbon nanotube-containing particles in ambient atmospheres.1.1.1 This test method is suitable for determination of carbon nanotubes in both ambient (outdoor) and building atmospheres.1.2 This test method is defined for polycarbonate capillary pore filters through which a known volume of air has been drawn and for blank filters.1.3 The direct analytical method cannot be used if the general particulate matter loading of the sample collection filter as analyzed exceeds approximately 25 % coverage of the collection filter by particulate matter.1.4 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Interlaminar delamination growth can be a critical failure mode in laminated CMC structures. Knowledge of the resistance to interlaminar delamination growth of a laminated CMC is essential for material development and selection, and for CMC component design. (See (1-8)3 which give GIc values of 20 J/m2 to 800 J/m2 for different CMC and carbon-carbon composite systems at ambient temperatures.)5.2 Conducting this test produces multiple values of GIc which are traditionally plotted against the delamination length at which that value was measured (see Fig. 2). The specific data of value to the test requestor will depend on the end use that motivated testing.5.2.1 The first increment of growth, initiated from a pre-implanted insert or machined notch, is sometimes described as the non-precracked (NPC) toughness. NPC toughness may be of interest, as it can represent manufacturing or processing defects, such as foreign object debris in a laminate or an error during machining.5.2.2 The next increment of growth, initiated from the sharp crack tip assumed to be present after the first increment, is sometimes defined as the precracked (PC) toughness. PC toughness may be of interest, as it is more representative of the resistance to delamination growth from a naturally occurring or damage-induced delamination.5.2.3 The remaining increments of growth, collectively forming an R-curve, provide information on how GIc evolves as the delamination advances. In unidirectional tape laminates, the R-curve is often increasing due to bridging of nested fibers across the delamination plane, artificially increasing GIc. For 2-D woven laminates for which there is little interply nesting, the R-curve may be flat.5.2.4 The increments of growth in which the R-curve is flat, and GIc has reached a steady state value defined as GIR, may be of interest and may also useful in design and analysis.5.3 This test method for measurement of GIc of CMC materials can serve the following purposes:5.3.1 To establish quantitatively the effect of CMC material variables (fiber interface coatings, matrix structure and porosity, fiber architecture, processing and environmental variables, conditioning/exposure treatments, etc.) on GIc and the interlaminar crack growth and damage mechanisms of a particular CMC material;5.3.2 To determine if a CMC material shows R-curve behavior where GIc changes with crack extension or reaches a stable value at a given amount of delamination growth. Fig. 2 shows R-curve behavior for a SiC-SiC composite (1);5.3.3 To develop delamination failure criteria and design allowables for CMC damage tolerance, durability or reliability analyses, and life prediction;NOTE 3: Test data can only reliably be used for this purpose if there is confidence that the test is yielding a material property and not a structural, geometry-dependent, property.5.3.4 To compare quantitatively the relative values of GIc for different CMC materials with different constituents and material properties, reinforcement architectures, processing parameters, or environmental exposure conditions; and5.3.5 To compare quantitatively the values of GIc obtained from different batches of a specific CMC material, to perform lot acceptance quality control, to use as a material screening criterion, or to assess batch variability.1.1 This test method describes the experimental methods and procedures for the determination of the critical mode I interlaminar strain energy release rate of continuous fiber- reinforced ceramic matrix composite (CMC) materials in terms of GIc. This property is also sometimes described as the mode I fracture toughness or the mode I fracture resistance.1.2 This test method applies primarily to ceramic matrix composite materials with a 2-D laminate structure, consisting of lay-ups of continuous ceramic fibers, in unidirectional tape or 2-D woven fabric architectures, within a brittle ceramic matrix.1.3 This test method determines the elastic strain energy released per unit of new surface area created as a delamination grows at the interlaminar interface between two lamina or plies. The term delamination is used in this test method to specifically refer to this type of growth, while the term crack is a more general term that can also refer to matrix cracking, intralaminar delamination growth, or fiber fracture.1.4 This test method uses a double cantilever beam (DCB) specimen to determine the critical mode I interlaminar strain energy release rate (GIc). A DCB test method has been standardized for polymer matrix composites (PMCs) under Test Method D5528. This test method addresses a similar procedure, but with modifications to account for the different physical properties, reinforcement architectures, stress-strain response, and failure mechanisms of CMCs compared to PMCs.1.5 This test is written for ambient temperature and atmospheric test conditions, but the test method can also be used for elevated temperature or environmental exposure testing with the use of an appropriate environmental test chamber, measurement equipment for controlling and measuring the chamber temperature, humidity, and atmosphere, high temperature gripping fixtures, and modified equipment for measuring delamination growth.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6.1 Values expressed in this test method are in accordance with the International System of Units (SI) and IEEE/ASTM SI 10.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Section 8.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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定价： 843元 加购物车

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4.1 This test method may be used for material development, material comparison, quality assurance, characterization, reliability assessment, and design data generation.4.2 Continuous fiber-reinforced ceramic matrix composites (CFCCs) are generally characterized by fine-grain sized (<50 μm) matrices and ceramic fiber reinforcements. In addition, continuous fiber-reinforced glass (amorphous) matrix composites can also be classified as CFCCs. Uniaxially loaded compressive strength tests provide information on mechanical behavior and strength for a uniformly stressed CFCC.4.3 Generally, ceramic and ceramic matrix composites have greater resistance to compressive forces than tensile forces. Ideally, ceramics should be compressively stressed in use, although engineering applications may frequently introduce tensile stresses in the component. Nonetheless, compressive behavior is an important aspect of mechanical properties and performance. The compressive strength of ceramic and ceramic composites may not be deterministic. Therefore, test a sufficient number of test specimens to gain an insight into strength distributions.4.4 Compression tests provide information on the strength and deformation of materials under uniaxial compressive stresses. Uniform stress states are required to effectively evaluate any nonlinear stress-strain behavior that may develop as the result of cumulative damage processes (for example, matrix cracking, matrix/fiber debonding, fiber fracture, delamination, etc.) that may be influenced by testing mode, testing rate, effects of processing or combination of constituent materials, or environmental influences. Some of these effects may be consequences of stress corrosion or sub-critical (slow) crack growth which can be minimized by testing at sufficiently rapid rates as outlined in this test method.4.5 The results of compression tests of test specimens fabricated to standardized dimensions from a particulate material or selected portions of a part, or both, may not totally represent the strength and deformation properties of the entire, full-size product or its in-service behavior in different environments.4.6 For quality control purposes, results derived from standardized compressive test specimens may be considered indicative of the response of the material from which they were taken for given primary processing conditions and post-processing heat treatments.4.7 The compressive behavior and strength of a CFCC are dependent on, and directly related to, the material. Analysis of fracture surfaces and fractography, though beyond the scope of this test method, are recommended.1.1 This test method covers the determination of compressive strength, including stress-strain behavior, under monotonic uniaxial loading of continuous fiber-reinforced advanced ceramics at ambient temperatures. This test method addresses, but is not restricted to, various suggested test specimen geometries as listed in the appendixes. In addition, test specimen fabrication methods, testing modes (force, displacement, or strain control), testing rates (force rate, stress rate, displacement rate, or strain rate), allowable bending, and data collection and reporting procedures are addressed. Compressive strength, as used in this test method, refers to the compressive strength obtained under monotonic uniaxial loading, where monotonic refers to a continuous nonstop test rate with no reversals from test initiation to final fracture.1.2 This test method applies primarily to advanced ceramic matrix composites with continuous fiber reinforcement: unidirectional (1D), bidirectional (2D), and tridirectional (3D) or other multi-directional reinforcements. In addition, this test method may also be used with glass (amorphous) matrix composites with 1D, 2D, 3D, and other multi-directional continuous fiber reinforcements. This test method does not directly address discontinuous fiber-reinforced, whisker-reinforced, or particulate-reinforced ceramics, although the test methods detailed here may be equally applicable to these composites.1.3 The values stated in SI units are to be regarded as the standard and are in accordance with IEEE/ASTM SI 10.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Refer to Section 7 for specific precautions.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This test method (also known as “tube burst test”) may be used for material development, material comparison, material screening, material down selection, and quality assurance. This test method can also be used for material characterization, design data generation, material model verification/validation, or combinations thereof.5.2 Continuous fiber-reinforced ceramic composites (CFCCs) are composed of continuous ceramic-fiber directional (1D, 2D, and 3D) reinforcements in a fine grain-sized (50 µm) ceramic matrix with controlled porosity. Often these composites have an engineered thin (0.1 to 10 µm) interface coating on the fibers to produce crack deflection and fiber pull-out.5.3 CFCC components have distinctive and synergistic combinations of material properties, interface coatings, porosity control, composite architecture (1D, 2D, and 3D), and geometric shapes that are generally inseparable. Prediction of the mechanical performance of CFCC tubes (particularly with braid and 3D weave architectures) may not be possible by applying measured properties from flat CFCC plates to the design of tubes. This is because fabrication/processing methods may be unique to tubes and not replicable to flat plates, thereby producing compositionally similar but structurally and morphologically different CFCC materials. In particular, tubular components comprised of CFCC material form a unique synergistic combination of material, geometric shape, and reinforcement architecture that are generally inseparable. In other words, prediction of mechanical performance of CFCC tubes generally cannot be made by using properties measured from flat plates. Strength tests of internally pressurized CFCC tubes provide information on mechanical behavior and strength for a multiaxially stressed material.5.4 Unlike monolithic advanced ceramics that fracture catastrophically from a single dominant flaw, CMCs generally experience “graceful” fracture from a cumulative damage process. Therefore, while the volume of material subjected to a uniform hoop tensile stress for a single uniformly pressurized tube test may be a significant factor for determining matrix cracking stress, this same volume may not be as significant a factor in determining the ultimate strength of a CMC. However, the probabilistic nature of the strength distributions of the brittle matrices of CMCs requires a statistically significant number of test specimens for statistical analysis and design. Studies to determine the exact influence of test specimen volume on strength distributions for CMCs have not been completed. It should be noted that hoop tensile strengths obtained using different recommended test specimens with different volumes of material in the gage sections may be different due to these volume effects.5.5 Hoop tensile strength tests provide information on the strength and deformation of materials under stresses induced from internal pressurization of tubes. Nonuniform stress states may be inherent in these types of tests and subsequent evaluation of any nonlinear stress-strain behavior must take into account the asymmetric behavior of the CMC under multiaxial stressing. This nonlinear behavior may develop as the result of cumulative damage processes (for example, matrix cracking, matrix/fiber de-bonding, fiber fracture, delamination, etc.) which may be influenced by testing mode, testing rate, processing or alloying effects, or environmental influences. Some of these effects may be consequences of stress corrosion or subcritical (slow) crack growth that can be minimized by testing at sufficiently rapid rates as outlined in this test method.5.6 The results of hoop tensile strength tests of test specimens fabricated to standardized dimensions from a particular material or selected portions of a part, or both, may not totally represent the strength and deformation properties of the entire full-size end product or its in-service behavior in different environments.5.7 For quality control purposes, results derived from standardized tubular hoop tensile strength test specimens may be considered indicative of the response of the material from which they were taken for, given primary processing conditions and post-processing heat treatments.5.8 The hoop tensile stress behavior and strength of a CMC are dependent on its inherent resistance to fracture, the presence of flaws, or damage accumulation processes, or both. Analysis of fracture surfaces and fractography, though beyond the scope of this test method, is highly recommended.1.1 This test method covers the determination of the hoop tensile strength, including stress-strain response, of continuous fiber-reinforced advanced ceramic tubes subjected to direct internal pressurization that is applied monotonically at ambient temperature. This type of test configuration is sometimes referred to as “tube burst test.” This test method is specific to tube geometries, because flaw populations, fiber architecture, material fabrication, and test specimen geometry factors are often distinctly different in composite tubes, as compared to flat plates.1.2 In the test method, a composite tube/cylinder with a defined gage section and a known wall thickness is loaded via internal pressurization from a pressurized fluid applied either directly to the material or through a secondary bladder inserted into the tube. The monotonically applied uniform radial pressure on the inside of the tube results in hoop stress-strain response of the composite tube that is recorded until failure of the tube. The hoop tensile strength and the hoop fracture strength are determined from the resulting maximum pressure and the pressure at fracture, respectively. The hoop tensile strains, the hoop proportional limit stress, and the modulus of elasticity in the hoop direction are determined from the stress-strain data. Note that hoop tensile strength as used in this test method refers to the tensile strength in the hoop direction from the introduction of a monotonically applied internal pressure where ‘monotonic’ refers to a continuous nonstop test rate without reversals from test initiation to final fracture.1.3 This test method applies primarily to advanced ceramic matrix composite tubes with continuous fiber reinforcement: unidirectional (1D, filament wound and tape lay-up), bidirectional (2D, fabric/tape lay-up and weave), and tridirectional (3D, braid and weave). These types of ceramic matrix composites can be composed of a wide range of ceramic fibers (oxide, graphite, carbide, nitride, and other compositions) in a wide range of crystalline and amorphous ceramic matrix compositions (oxide, carbide, nitride, carbon, graphite, and other compositions).1.4 This test method does not directly address discontinuous fiber-reinforced, whisker-reinforced, or particulate-reinforced ceramics, although the test methods detailed here may be equally applicable to these composites.1.5 The test method is applicable to a range of test specimen tube geometries based on the intended application that includes composite material property and tube radius. Lengths of the composite tube, length of the pressurized section, and length of tube overhang are determined so as to provide a gage length with uniform internal radial pressure. A wide range of combinations of material properties, tube radii, wall thicknesses, tube lengths, and lengths of pressurized section are possible.1.5.1 This test method is specific to ambient temperature testing. Elevated temperature testing requires high-temperature furnaces and heating devices with temperature control and measurement systems and temperature-capable pressurization methods which are not addressed in this test method.1.6 This test method addresses tubular test specimen geometries, test specimen preparation methods, testing rates (that is, induced pressure rate), and data collection and reporting procedures in the following sections:           Section 1          Referenced Documents Section 2          Terminology Section 3          Summary of Test Method Section 4           Section 5          Interferences Section 6          Apparatus Section 7          Hazards Section 8          Test Specimens Section 9          Test Procedure Section 10          Calculation of Results Section 11          Report Section 12          Precision and Bias Section 13          Keywords Section 14          Appendix            References  1.7 Values expressed in this test method are in accordance with the International System of Units (SI) and IEEE/ASTM SI 10.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in Section 8.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Polycyclic aromatic hydrocarbons (PAH) as defined by this test method are compounds made up of two or more fused aromatic rings.5.2 Several PAH are considered to be probable human carcinogens.5.3 PAH are emitted in the atmosphere primarily through wood or fossil fuel combustion.5.4 Two- and three-ring PAH are typically present in urban air at concentrations ranging from 10 to several hundred nanograms per cubic metre (ng/m3); those with four or more rings are usually found at concentrations of a few ng/m3 or lower.5.5 PAH span a broad spectrum of vapor pressures (for example, from 1.1 × 10–2 kPa for naphthalene to 2 × 10–13 kPa for coronene at 25 °C). Table 1 lists some PAH that are frequently found in ambient air. Those with vapor pressures above about 10–8 kPa will be present in the ambient air substantially distributed between the gas and particulate phases. This test method will permit the collection of both phases. However, particulate-phase PAH will tend to be lost from the particulate filter during sampling due to desorption and volatilization.(A) Many of these compounds sublime.5.5.1 The distribution between phases depends on ambient temperature, humidity, types and concentrations of PAH and particulate matter, and residence time in the air. PAH, especially those having vapor pressures above 10–8 kPa, may vaporize from particulate filters during sampling. Consequently, a back-up vapor trap must be used for efficient sampling.5.6 Separate analyses of the filter and vapor trap will not reflect the original atmospheric phase distributions and should be discouraged.1.1 This test method2 specifies sampling, cleanup, and analysis procedures for the determination of polycyclic aromatic hydrocarbons (PAH) in ambient air.1.2 This test method is designed to collect both gas-phase and particulate-phase PAH and to determine them collectively.1.3 This test method is a high-volume sampling (100 to 250 L/min) method capable of detecting PAH at sub-nanograms per cubic metre (ng/m3) concentrations with sampling volumes up to 350 m3 of air.1.4 This test method has been validated for sampling periods up to 24 h.1.5 Precision and bias under normal conditions can be expected to be ±35 to 50 %.1.6 This test method describes a sampling and analysis procedure for PAH that involves collection from air on a combination fine-particle filter and sorbent trap and subsequent analysis by gas chromatography/mass spectrometry (GC/MS).1.7 The range of this test method is approximately 0.05 to 1000 ng/m3 of air sampled.1.8 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.9 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. See also Section 8 for additional safety precautions.1.10 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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