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Contaminants that will reduce the effective life of electron devices may enter the device through small leaks. These leaks are most frequently found at seals between parts of the same or dissimilar materials. Leaks may also result from porosity of a defective portion of the case.Dye-penetrant procedures are applicable only to individual gross leaks in a system. The presence of a number of small leaks that may result in a cumulatively unacceptable leak rate when measured by other techniques will not be indicated if each individual leak is below the level of sensitivity of the test.There is no general agreement concerning level of leakage which is likely to be deleterious to a particular device. However, since these tests are designed to detect gross leakage, components that exhibit any indication of leakage are normally rejected.Since leaks may change in size with different ambient conditions, comparisons between test stations are not conclusive. Therefore these methods are usually employed as go, no-go tests.1.1 These practices cover procedures that will normally detect and locate the sites of gross leaks in electron devices.1.2 These procedures are suitable for use on selected parts during receiving inspection or to verify and locate leakage sites for production control. They are not quantitative; no indication of leak size can be inferred from the test.1.3 These procedures are most suitable for use on transparent glass-encased devices; all methods are applicable to transparent parts with an internal cavity. Method A, Penetrant-Capillary, is also applicable to parts, such as terminals, end seals or base assemblies, without an internal cavity, and Method C, Penetrant-Pressure Followed by Vacuum, can be used on opaque parts with an internal cavity. Method B, Penetrant-Pressure, can also be used on opaque parts with an internal cavity if the part is opened after dye penetration and before inspection. Parts that have an internal cavity may either contain gas (such as air, nitrogen, nitrogen-helium mixture, etc.) or be evacuated. These procedures are not suitable for use on grease-filled components.1.4 Because of the possibility of dye entrapment between the component and an attached part, components with mechanically attached parts, such as a radiator on a power transistor, should be tested before the attachment is made or after it has been removed.Note 1—Alternative methods for determining hermeticity of electron devices may be found in Practices F 98 (see 2.1) and Test Methods F 134 (see 2.1).1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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 and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard statement, see Section 8.

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1.1 These test methods cover the testing of methylcellulose. 1.2 The test methods appear in the following order: Sections Moisture 4 and 5 Ash-as Sulfate 6 to 8 Chlorides-as Sodium Chloride 9 to 11 Alkalinity-as Na2CO3 12 to 14 Iron 15 to 19 Heavy Metals 20 to 22 Methoxyl Content 23 to 26 Viscosity: Water-Soluble Methylcellulose 27 to 29 Alkali-Soluble Methylcellulose 30 to 31 pH 32 Solids 33 to 34 Density 35 to 39 1.3 This standard does not purport to address the safety problems, 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.> For a specific hazard statement, see Note 1.

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5.1 The significant features are typified by a discussion of the limitations of the technique. With the description and arrangement given in the following portions of this test method, the instrument will record directly the normal spectral emittance of a specimen. However, the following conditions must be met within acceptable tolerance:5.1.1 The effective temperatures of the specimen and blackbody must be within 1 K of each other. Practical limitations arise, however, because the temperature uniformities are often not better than a few degrees Kelvin.5.1.2 The optical path length in the two beams must be equal, or the instrument should operate in a nonabsorbing atmosphere or a vacuum, in order to eliminate the effects of differential atmospheric absorption in the two beams. Measurements in air are in many cases important, and will not necessarily give the same results as in a vacuum, thus the equality of the optical paths for dual beam instruments becomes very critical.NOTE 3: Very careful optical alignment of the spectrophotometer is required to minimize differences in absorptance along the two paths of the instrument, and careful adjustment of the chopper timing to reduce “cross-talk” (the overlap of the reference and sample signals) as well as precautions to reduce stray radiation in the spectrometer are required to keep the zero line flat. With the best adjustment, the “100 % line” will be flat to within 3 %; both of these measurements should be reproducible within these limits (see 7.3, Note 6).5.1.3 Front-surface mirror optics must be used throughout, except for the prism in prism monochromators and the grating in grating monochromators, and it should be emphasized that equivalent optical elements must be used in the two beams in order to reduce and balance attenuation of the beams by absorption in the optical elements. It is recommended that optical surfaces be free of SiO2 and SiO coatings; MgF2 may be used to stabilize mirror surfaces for extended periods of time. The optical characteristics of these coatings are critical, but can be relaxed if all optical paths are fixed during measurements or the incident angles are not changed between modes of operation (during “0 % line,” “100 % line,” and sample measurements). It is recommended that all optical elements be adequately filled with energy.5.1.4 The source and field apertures of the two beams must be equal in order to ensure that radiant flux in the two beams compared by the apparatus will pertain to equal areas of the sources and equal solid angles of emission. In some cases it may be desirable to define the solid angle of the source and sample when comparing alternative measurement techniques.5.1.5 The response of the detector-amplifier system must vary linearly with the incident radiant flux.1.1 This test method describes a highly accurate technique for measuring the normal spectral emittance of electrically conducting materials or materials with electrically conducting substrates, in the temperature range from 600 to 1400 K, and at wavelengths from 1 to 35 μm.1.2 The test method requires expensive equipment and rather elaborate precautions, but produces data that are accurate to within a few percent. It is suitable for research laboratories where the highest precision and accuracy are desired, but is not recommended for routine production or acceptance testing. However, because of its high accuracy this test method can be used as a referee method to be applied to production and acceptance testing in cases of dispute.1.3 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.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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1.1 This test method covers the determination of capillary-moisture properties of fine-textured soils as indicated by the moisture content - moisture tension relationships determined by pressure-membrane apparatus using tensions between 1 and 15 atm (101 and 1520 kPa). Moisture tension (matrix suction) is defined as the equivalent negative gage pressure, or suction, in soil moisture. The test result is a moisture content which is a measure of the water retained in the soil subjected to a given soil - water tension (or at an approximately equivalent height above the water table). Note 1--For determination of capillary-moisture relationships of coarse- and medium-textured soils, refer to Test Method D2325. 1.2 This standard does not purport to address all of the safety problems, 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.

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This specification covers type 58 borosilicate sealing glass for use in electronic applications. The glass material shall conform to the chemical composition requirements prescribed. The material shall conform to the physical and electrical properties prescribed. The glass shall have a finish that ensures smooth, even surfaces and freedom from cracks, checks, bubbles, and other flaws of a character detrimental to the strength or life of the component or device for which its use is intended. The softening point and annealing point shall be tested to meet the requirements prescribed. The thermal expansion coefficient of the glass material shall be determined using the required procedure. The contracting coefficient of the glass material shall be tested to meet the requirements prescribed. The thermal contraction match between the glass and a sealing alloy may be determined by preparing and testing an assembly to meet the requirements prescribed.1.1 This specification covers Type 58 borosilicate sealing glass for use in electronic applications.NOTE 1: This specification is primarily intended to consider glass as most generally used, that is, glass in its transparent form as normally encountered in fabricating electronic devices. X1.3 refers to a sealing alloy that is compatible with this glass. Type 58 glass in other forms such as powdered, crushed, sintered, fibrous, etc., are excluded. The requirements of this specification, as applied to these forms, must be established in the raw glass prior to its conversion.1.2 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 Gasket compressions produced by bolt loads in a flanged joint are important in the application engineering of a joint assembly. They are related to the ability of a gasket to seal, to maintain tightness on assembly bolts, and to a variety of other gasket properties that determine the service behavior of a joint assembly. Thus, being able to determine the degree of compression in a gasket under the bolt loading will permit one to make qualitative predictions of the behavior of a joint assembly when it comes in contact with the application or service environment. With the plug test, bending of a flange facing between bolt centers can be measured; however, in a few highly distortable flanges the maximum bending between bolt centers may not be detected.4.2 The variation in gasket compressions at selected points in a flat-face joint assembly reveals the degree of flange distortion or the ability of the flange to distribute satisfactorily the compressive forces from bolt loads throughout the gasket.1.1 This practice permits measurement of gasket compression resulting from bolt loading on a flat-face joint assembly at ambient conditions.1.2 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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1.1 This test method covers the measurement of effective pumping speed of complete vacuum-chamber systems. The test method is suitable for all types of vacuum systems operating at pressures below 1 X 10 torr and for chambers larger than approximately 10 ft (0.3 m ). 1.2 The values stated in inch-pound units are to be regarded as the 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 and health practices and determine the applicability of regulatory limitations prior to use.

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3.1 It is difficult to overemphasize the importance of the spall test. Porcelain enameled aluminum that fails this test will probably spall in service if subjected to moisture or weathering.1.1 These test methods cover accelerated determination of the resistance of porcelain enamel coatings on aluminum alloys to spalling from exposure to moisture or weathering. Test Method A,2 using a 5 % solution of ammonium chloride, requires 96-h immersion while Test Method B,3 using a 1 % solution of antimony trichloride, is completed after 20 h of immersion. The spalling tendency is evaluated by the same criteria in both methods. While either method is suitable for magnesium silicon alloys, such as 6061, Test Method B is preferred for simple alloys or commercially pure aluminum, such as 1100.1.2 The test methods appear in the following order:  SectionsTest Method A—Ammonium Chloride  4 – 9Test Method B—Antimony Trichloride 10 – 151.3 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： 515元 / 折扣价： 438 元 加购物车

定价： 515元 / 折扣价： 438 元 加购物车