4.1 This test method may be used for material development, material comparison, quality assurance, characterization, and design data generation.4.2 Generally, resistance to compression is the measure of the greatest strength of a monolithic advanced ceramic. 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. Although tensile strength distributions of ceramics are probabilistic and can be described by a weakest-link failure theory, such descriptions have been shown to be inapplicable to compressive strength distributions in at least one study (1).3 However, the need to test a statistically significant number of compressive test specimens is not obviated. Therefore, a sufficient number of test specimens at each testing condition is required for statistical analysis and design.4.3 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 which may develop as the result of cumulative damage processes (for example, microcracking) which may be influenced by testing mode, testing rate, processing or compositional effects, microstructure, or environmental influences.4.4 The results of compression 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 in the entire full-size product or its in-service behavior in different environments.4.5 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.1.1 This test method covers the determination of compressive strength including stress-strain behavior, under monotonic uniaxial loading of advanced ceramics at ambient temperature. This test method is restricted to specific test specimen geometries. In addition, test specimen fabrication methods, testing modes (force or displacement), 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. Monotonic loading refers to a test conducted at a constant rate in a continuous fashion, with no reversals from test initiation to final fracture.1.2 This test method is intended primarily for use with advanced ceramics that macroscopically exhibit isotropic, homogeneous, continuous behavior. While this test method is intended for use on monolithic advanced ceramics, certain whisker- or particle-reinforced composite ceramics, as well as certain discontinuous fiber-reinforced composite ceramics, may also meet these macroscopic behavior assumptions. Generally, continuous fiber ceramic composites (CFCCs) do not macroscopically exhibit isotropic, homogeneous, continuous behavior and, application of this test method to these materials is not recommended.1.3 Values expressed in this test method are in accordance with the International System of Units (SI) and 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.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.

定价： 646元 加购物车

定价： 646元 加购物车

定价： 646元 加购物车

4.1 This test method may be used for material development, material comparison, quality assurance, characterization, and design code or model verification.4.2 Engineering applications of ceramics frequently involve biaxial tensile stresses. Generally, the resistance to equibiaxial flexure is the measure of the least flexural strength of a monolithic advanced ceramic. The equibiaxial flexural strength distributions of ceramics are probabilistic and can be described by a weakest-link failure theory (1, 2).4 Therefore, a sufficient number of test specimens at each testing condition is required for statistical estimation or the equibiaxial strength.4.3 Equibiaxial strength tests provide information on the strength and deformation of materials under multiple tensile stresses. Multiaxial stress states are required to effectively evaluate failure theories applicable to component design, and to efficiently sample surfaces that may exhibit anisotropic flaw distributions. Equibiaxial tests also minimize the effects of test specimen edge preparation as compared to uniaxial tests because the generated stresses are lowest at the test specimen edges.4.4 The test results of equibiaxial test specimens fabricated to standardized dimensions from a particular material or selected portions of a component, or both, may not totally represent the strength properties in the entire full-size component or its in-service behavior in different environments.4.5 For quality control purposes, results derived from standardized equibiaxial test specimens may be considered indicative of the response of the bulk material from which they were taken for any given primary processing conditions and post-processing heat treatments or exposures.1.1 This test method covers the determination of the equibiaxial strength of advanced ceramics at ambient temperature via concentric ring configurations under monotonic uniaxial loading. In addition, test specimen fabrication methods, testing modes, testing rates, allowable deflection, and data collection and reporting procedures are addressed. Two types of test specimens are considered: machined test specimens and as-fired test specimens exhibiting a limited degree of warpage. Strength as used in this test method refers to the maximum strength obtained under monotonic application of load. Monotonic loading refers to a test conducted at a constant rate in a continuous fashion, with no reversals from test initiation to final fracture.1.2 This test method is intended primarily for use with advanced ceramics that macroscopically exhibit isotropic, homogeneous, continuous behavior. While this test method is intended for use on monolithic advanced ceramics, certain whisker- or particle-reinforced composite ceramics, as well as certain discontinuous fiber-reinforced composite ceramics, may also meet these macroscopic behavior assumptions. Generally, continuous fiber ceramic composites do not macroscopically exhibit isotropic, homogeneous, continuous behavior, and the application of this test method to these materials is not recommended.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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.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 Most oxides of nitrogen are formed during high-temperature combustion. The U.S. Environmental Protection Agency (EPA) has set primary and secondary air quality standards for NO2 that are designed to protect the public health and the public welfare (40 CFR, Part 50).5.2 Oxides of nitrogen are generated by many industrial processes that can result in employee exposures. These are regulated by the Occupational Safety and Health Administration (OSHA), which has promulgated exposure limits for the industrial working environment (29 CFR, Part 1910).5.3 These test methods have been found to be satisfactory for measuring oxides of nitrogen in ambient and workplace atmospheres over the ranges shown in 1.1.1.1 These test methods cover procedures for the continuous determination of total nitrogen dioxide (NO2) and nitric oxide (NO) as NOx, or nitric oxide (NO) alone or nitrogen dioxide (NO2) alone, in the ranges shown in the following table:  Approximate Range of Concentration(25°C and 101.3 kPa (1 atm))     Gas Ambient Atmosphere Workplace Atmosphere  μg/m3 (ppm) mg/m3 (ppm)     NO 10 to 600 (0.01 to 0.5) 0.6 to 30 (0.5 to 25)(NO + NO2) = NOx 20 to 1000 (0.01 to 0.05) 1 to 50 (0.5 to 25) NO2 20 to 1000 (0.01 to 0.5) 1 to 50 (0.5 to 25) 1.2 The test methods are based on the chemiluminescent reaction between nitric oxide and ozone.1.3 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.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. For specific precautionary statements, see Section 9.1.5 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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4.1 Strain gages are the most widely used devices for measuring strains and for evaluating stresses in structures. In many applications there are often cyclic loads that can cause strain gage failure. Performance characteristics of strain gages are affected by both the materials from which they are made and their geometric design.4.2 The determination of most strain gage performance characteristics requires mechanical testing that is destructive. Since strain gages tested for fatigue life cannot be used again, it is necessary to treat data statistically. In general, longer and wider strain gages with lower resistances will have greater fatigue life. Optional additions to strain gages (integral lead wires are an example) will often reduce fatigue life.4.3 To be used, strain gages must be bonded to a structure. Good results, particularly in a fatigue environment, depend heavily on the materials used to clean the bonding surface, to bond the strain gage, and to provide a protective coating. Skill of the installer is another major factor in success. Finally, instrumentation systems shall be carefully selected and calibrated to ensure that they do not unduly degrade the performance of the strain gages.4.4 Fatigue failure of a strain gage often does not involve visible cracking or fracture of the strain gage, but merely sufficient zero shift to compromise the accuracy of the strain gage output for static strain components.1.1 This test method covers a uniform procedure for the determination of strain gage fatigue life at ambient temperature. A suggested testing equipment design is included.1.2 This test method does not apply to force transducers or extensometers that use metallic bonded resistance strain gages as sensing elements.1.3 Strain gages are part of a complex system that includes structure, adhesive, strain gage, lead wires, instrumentation, and (often) environmental protection. As a result, many things affect the performance of strain gages, including user technique. A further complication is that strain gages, once installed, normally cannot be reinstalled in another location. Therefore, it is not possible to calibrate individual strain gages; performance characteristics are normally presented on a statistical basis.1.4 This test method encompasses only fully reversed stain cycles.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.

定价： 590元 加购物车

定价： 590元 加购物车

定价： 590元 加购物车

定价： 843元 加购物车

4.1 This test method may be used for material development, quality control, characterization, and design data generation purposes. This test method is intended to be used with ceramics whose strength is 50 MPa (~7 ksi) or greater. The test method may also be used with glass test specimens, although Test Methods C158 is specifically designed to be used for glasses. This test method may be used with machined, drawn, extruded, and as-fired round specimens. This test method may be used with specimens that have elliptical cross section geometries.4.2 The flexure strength is computed based on simple beam theory with assumptions that the material is isotropic and homogeneous, the moduli of elasticity in tension and compression are identical, and the material is linearly elastic. The average grain size should be no greater than one-fiftieth of the rod diameter. The homogeneity and isotropy assumptions in the standard rule out the use of this test for continuous fiber-reinforced ceramics.4.3 Flexural strength of a group of test specimens is influenced by several parameters associated with the test procedure. Such factors include the loading rate, test environment, specimen size, specimen preparation, and test fixtures (1-3).3 This method includes specific specimen-fixture size combinations, but permits alternative configurations within specified limits. These combinations were chosen to be practical, to minimize experimental error, and permit easy comparison of cylindrical rod strengths with data for other configurations. Equations for the Weibull effective volume and Weibull effective surface are included.4.4 The flexural strength of a ceramic material is dependent on both its inherent resistance to fracture and the size and severity of flaws in the material. Flaws in rods may be intrinsically volume-distributed throughout the bulk. Some of these flaws by chance may be located at or near the outer surface. Flaws may alternatively be intrinsically surface-distributed with all flaws located on the outer specimen surface. Grinding cracks fit the latter category. Variations in the flaws cause a natural scatter in strengths for a set of test specimens. Fractographic analysis of fracture surfaces, although beyond the scope of this standard, is highly recommended for all purposes, especially if the data will be used for design as discussed in Refs (3-5) and Practices C1322 and C1239.4.5 The three-point test configuration exposes only a very small portion of the specimen to the maximum stress. Therefore, three-point flexural strengths are likely to be greater than four-point flexural strengths. Three-point flexure has some advantages. It uses simpler test fixtures, it is easier to adapt to high temperature and fracture toughness testing, and it is sometimes helpful in Weibull statistical studies. It also uses smaller force to break a specimen. It is also convenient for very short, stubby specimens which would be difficult to test in four-point loading. Nevertheless, four-point flexure is preferred and recommended for most characterization purposes.1.1 This test method is for the determination of flexural strength of rod-shaped specimens of advanced ceramic materials at ambient temperature. In many instances it is preferable to test round specimens rather than rectangular bend specimens, especially if the material is fabricated in rod form. This method permits testing of machined, drawn, or as-fired rod-shaped specimens. It allows some latitude in the rod sizes and cross section shape uniformity. Rod diameters between 1.5 and 8 mm and lengths from 25 to 85 mm are recommended, but other sizes are permitted. Four-point-1/4-point as shown in Fig. 1 is the preferred testing configuration. Three-point loading is permitted. This method describes the apparatus, specimen requirements, test procedure, calculations, and reporting requirements. The method is applicable to monolithic or particulate- or whisker-reinforced ceramics. It may also be used for glasses. It is not applicable to continuous fiber-reinforced ceramic composites.FIG. 1 Four-Point-1/4-Point Flexure Loading Configuration1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.3 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.1.4 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 Standards for O3 in the atmosphere have been promulgated by government authorities to protect the health and welfare of the public (6) and also for the protection of industrial workers (7). 5.2 Although O3 itself is a toxic material, in ambient air it is primarily the photochemical oxidants formed along with O3 in polluted air exposed to sunlight that cause smog symptoms such as lachrymation and burning eyes. Ozone is much more easily monitored than these photochemical oxidants and provides a good indication of their concentrations, and it is therefore the substance that is specified in air quality standards and regulations. 1.1 This test method describes the sampling and continuous analysis of ozone (O3) in the atmosphere at concentrations ranging from 10 to 2000 μg/m3 of O3 in air (5 ppb(v) to 1 ppm(v)). 1.1.1 The test method is limited to applications by its sensitivity to interferences as described in Section 6. The interference sensitivities may limit its use for ambient and workplace atmospheres. 1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.3 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. 1.4 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.

定价： 590元 加购物车

定价： 646元 加购物车

定价： 590元 加购物车

5.1 An acute effluent toxicity test is conducted to obtain information concerning the immediate effects on test organisms of a short-term exposure to an effluent under specific experimental conditions. One can directly examine acute effects of complex mixtures of chemicals as occurs in effluents and some ambient waters. Acute effluent toxicity tests can be used to evaluate the potential for designated-use or aquatic life impairment in the receiving stream, lake, or estuary. An acute toxicity test does not provide information about whether delayed effects will occur, although a post-exposure observation period, with appropriate feeding if necessary, might provide such information.5.2 Results of acute effluent tests might be used to predict acute effects likely to occur on aquatic organisms in field situations as a result of exposure under comparable conditions, except that (1) motile organisms might avoid exposure when possible, (2) toxicity to benthic species might be dependent on sorption or settling of components of the effluent onto the substrate, and (3) the effluent might physically or chemically interact with the receiving water.5.3 Results of acute effluent tests might be used to compare the acute sensitivities of different species and the acute toxicities of different effluents, and to study the effects of various environmental factors on results of such tests.5.4 Acute tests are usually the first step in evaluating the effects of an effluent on aquatic organisms.5.5 Results of acute effluent tests will depend on the temperature, composition of the dilution water, condition of the test organisms, exposure technique, and other factors.AbstractThis guide covers procedures for obtaining laboratory data concerning the adverse effects of aqueous ambient samples and effluents on certain species of freshwater and saltwater fishes, macroinvertebrates, and amphibians, during a short-term exposure, depending on the species, using the static, renewal, and flow-through techniques. These procedures will probably be useful for conducting acute toxicity tests on aqueous effluents with many other aquatic species, although modifications might be necessary. Static tests might not be applicable to effluents that have a high oxygen demand, or contain materials that (1) are highly volatile, (2) are rapidly biologically or chemically transformed in aqueous solutions, or (3) are removed from test solutions in substantial quantities by the test chambers or organisms during the test. Results of acute toxicity tests should usually be reported in terms of a median lethal concentration (LC50) or median effective concentration (EC50). An acute toxicity test does not provide information about whether delayed effects will occur. Specified requirements involving the following are detailed: (1) hazards; (2) apparatus: facilities, special requirements, construction materials, metering system, test chambers, cleaning, and acceptability; (3) dilution water requirements, source, treatment, and characterization; (4) effluent sampling point, collection, preservation, treatment, and test concentrations; (5) test organism species, age, source, care and handling, feeding, disease treatment, holding, acclimation, and quality; (6) procedure: experimental design, dissolved oxygen, temperature, loading, beginning the test, feeding, duration of test, biological data, and other measurements; (7) analytical methodology; (8) acceptability of test; (9) calculation of results; and (1) report of results.1.1 This guide covers procedures for obtaining laboratory data concerning the adverse effects of an aqueous effluent on certain species of freshwater and saltwater fishes, macroinvertebrates, and amphibians, usually during 2 day to 4 day exposures, depending on the species, using the static, renewal, and flow-through techniques. These procedures will probably be useful for conducting acute toxicity tests on aqueous effluents with many other aquatic species, although modifications might be necessary.1.2 Other modifications of these procedures might be justified by special needs or circumstances. Although using appropriate procedures is more important than following prescribed procedures, results of tests conducted using unusual procedures are not likely to be comparable to results of many other tests. Comparison of results obtained using modified and unmodified versions of these procedures might provide useful information concerning new concepts and procedures for conducting acute toxicity tests on aqueous effluents.1.3 This guide is based in large part on Guide E729 where addition details are provided for test elements that may be applicable to the ambient and effluent toxicity testing described in this method. The major differences between the two guides are (1) the maximum test concentration is 100 % effluent or ambient sample, (2) testing is not chemical-specific, and (3) the holding time of effluent and ambient samples is often considerably less than that for chemicals and other test materials. Because the sample is often a complex mixture of chemicals, analytical tests cannot generally be used to confirm exposure concentrations.1.4 Selection of the technique to be used in a specific situation will depend upon the needs of the investigator and upon available resources. Static tests provide the most easily obtained measure of acute toxicity but should not last longer than 48 h. Renewal and flow-through tests may last longer than 48 h because the pH and concentrations of dissolved oxygen and effluent are maintained at desired levels and degradation and metabolic products are removed. Static tests might not be applicable to effluents that have a high oxygen demand or contain materials that (1) are highly volatile, (2) are rapidly biologically or chemically transformed in aqueous solutions, or (3) are removed from test solutions in substantial quantities by the test chambers or organisms during the test. Flow-through tests are generally preferable to renewal tests, although in some situations a renewal test might be more cost-effective than a flow-through test.1.5 In the development of these procedures, an attempt was made to balance scientific and practical considerations and to ensure that the results will be sufficiently accurate and precise for the applications for which they are commonly used. A major consideration was that the common uses of the results of acute tests on effluents do not require or justify stricter requirements than those set forth in this guide. Although the tests may be improved by using more organisms, longer acclimation times, and so forth, the requirements presented in this guide should usually be sufficient.1.6 Results of acute toxicity tests should usually be reported in terms of a median lethal concentration (LC50) or median effective concentration (EC50). In some situations, it might be necessary only to determine whether a specific concentration is acutely toxic to the test species or whether the LC50 or EC50 is above or below a specific concentration.1.7 This guide is arranged as follows:  Section   Referenced Documents   2Terminology   3Summary of Guide   4   5Hazards   7Apparatus   6 Facilities   6.1 Special Requirements   6.2 Construction Materials   6.3 Metering System   6.4 Test Chambers   6.5 Cleaning   6.6 Acceptability   6.7Dilution Water   8 Requirements   8.1 Source   8.2 Treatment   8.3 Characterization   8.4Effluent   9 Sampling Point   9.1 Collection   9.2 Preservation   9.3 Treatment   9.4 Test Concentration(s)   9.5Test Organisms   10 Species   10.1 Age   10.2 Source   10.3 Care and Handling   10.4 Feeding   10.5 Disease Treatment   10.6 Holding   10.7 Acclimation   10.8 Quality   10.9Procedure   11 Experimental Design   11.1 Dissolved Oxygen   11.2 Temperature   11.3 Loading   11.4 Beginning the Test   11.5 Feeding   11.6 Duration of Test   11.7 Biological Data   11.8 Other Measurements   11.9Analytical Methodology   12Acceptability of Test   13Calculation or Results   14Report   151.8 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 7.1.9 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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This specification covers the standard for all metal prefabricated, reflective insulation systems for equipment and piping operating at temperatures above ambient in air proposed for use in nuclear power-generating plants and industrial plants. The insulation unit is a rigid, self-contained, prefabricated metal construction made of an inner and outer casing arranged to form a rigid assembly with separated air spaces between the inner and outer casing and the individual reflective liners. The reflective insulation described herein is limited to systems of insulating units, designed to fit the equipment or piping to be insulated. The units shall be manufactured from metals that are in accordance with the thermal, physical, and chemical requirements not only of the insulation as unit, but also as an assembly of units forming the insulation system.1.1 This specification covers the requirements for all metal prefabricated, reflective insulation systems for equipment and piping operating in air at temperatures above ambient. Typical applications are in nuclear power-generating plants and industrial plants.1.2 Reflective insulation is thermal insulation that reduces radiant heat transfer across spaces by the use of surfaces of high reflectance and low emittance.1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.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.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.

定价： 590元 加购物车