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The reaction thresholds of a material are a measure of the tendency of the material or its decomposition products to undergo gas phase reactions of various types. Hot-flame and cool-flame thresholds relate directly to reactions which are involved in autoignition phenomena. Pre-flame, catalytic and thermal polymerization thresholds also relate to autoignition in that they represent reactions which can be under some conditions the precursors of ignition reactions.1.1 This test method covers determination of the pre-flame, cool-flame, and hot-flame reaction threshold temperatures and the incipient reaction temperature of liquids and solids. Data may be obtained at pressures from low vacuum to 0.8 MPa (115 psia) for temperatures within the range from room temperature to 925 K (1200°F).1.2 This test method may be applied to any substance that is a liquid or a solid at room temperature and atmospheric pressure and that, at room temperature, is compatible with glass and stainless steel. Air is the intended oxidizing medium; however, other media may be substituted provided appropriate precautions are taken for their safe use.1.3 The values stated in SI units are to be regarded as the standard. In cases where materials, products, or equipment are available in inch-pound units only, SI units are omitted.1.4 This standard is used to measure and describe the response of materials, products, or assemblies to heat and flame under controlled conditions, but does not by itself incorporate all factors required for fire hazard or fire risk assessment of the materials, products, or assemblies under actual fire conditions.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 and health practices and determine the applicability of regulatory limitations prior to use. For specific warning statements, see 6.8, Sections 7 and 9.

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ASTM F617-00 Standard Test Method for Measuring MOSFET Linear Threshold Voltage (Withdrawn 2006) Withdrawn, No replacement 发布日期 :  1970-01-01 实施日期 : 

1.1 This test method covers the measurement of MOSFET (see Note 1) linear threshold voltage under very low sweep rate or d-c conditions. It is a d-c conductance method applicable in the linear region of MOSFET operation where a drain voltage V D of approximately 0.1 V is typical.Note 1--MOS is an acronym for metal-oxide semiconductor; FET is an acronym for field-effect transistor.1.2 This test method is applicable to both enhancement-mode and depletion-mode MOSFETs, and for both silicon-on-insulator (SOI) and bulk-silicon MOSFETs. The test method specifies positive voltage and current conventions specifically applicable to n-channel MOSFETs. The substitution of negative voltage and negative current make the test method directly applicable to p-channel MOSFETs.1.3 The values stated in International System of Units (SI) are to be regarded as standard. No other units of measurement are included in this test method.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.

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4.1 When this test method is used to measure the threshold impact sensitivity of a material, a relative sensitivity assessment is obtained which permits the ranking of materials.4.2 This test method may also be used for acceptance-testing materials for use in liquid oxygen systems. Twenty separate samples of the material submerged in liquid oxygen are subjected to 98 J (72 ft·lbf) or as specified. Impact energy delivered through a 12.7-mm (1/2-in.) diameter contact. More than one indication of sensitivity is cause for immediate rejection. A single explosion, flash, or other indication of sensitivity during the initial series of 20 tests requires that an additional 40 samples be tested without incident to ensure acceptability of the material.4.3 The threshold values are determined by this test method at ambient pressure. The sensitivity of materials to mechanical impact is known to increase with increasing pressure. Since most liquid oxygen systems operate at pressures above ambient condition, some consideration should be given to increased sensitivity and reactivity of materials at higher pressure when selecting materials for use in pressurized system.1.1 This method2,3,4 covers the determination of compatibility and relative sensitivity of materials with liquid oxygen under impact energy using the Army Ballistic Missile Agency (ABMA)-type impact tester. Materials that are impact-sensitive with liquid oxygen are generally also sensitive to reaction by other forms of energy in the presence of oxygen.1.2 This standard should be used to measure and describe the properties of materials, products, or assemblies in response to heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fire hazard or fire risk of materials, products, or assemblies under actual fire conditions. However, results of this test may be used as elements of a fire risk assessment which takes into account all of the factors which are pertinent to an assessment of the fire hazard of a particular end use.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.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 The electrical properties of gate and field oxides are altered by ionizing radiation. The method for determining the dose delivered by the source irradiation is discussed in Practices E666, E668, E1249, and Guide E1894. The time dependent and dose rate effects of the ionizing radiation can be determined by comparing pre- and post-irradiation voltage shifts, ΔVot and ΔVit. This test method provides a means for evaluation of the ionizing radiation response of MOSFETs and isolation parasitic MOSFETs.5.2 The measured voltage shifts, ΔVot and ΔVit, can provide a measure of the effectiveness of processing variations on the ionizing radiation response.5.3 This technique can be used to monitor the total-dose response of a process technology.1.1 This test method covers the use of the subthreshold charge separation technique for analysis of ionizing radiation degradation of a gate dielectric in a metal-oxide-semiconductor-field-effect transistor (MOSFET) and an isolation dielectric in a parasitic MOSFET.2,3,4 The subthreshold technique is used to separate the ionizing radiation-induced inversion voltage shift, ΔVINV into voltage shifts due to oxide trapped charge, ΔVot and interface traps, ΔV it. This technique uses the pre- and post-irradiation drain to source current versus gate voltage characteristics in the MOSFET subthreshold region.1.2 Procedures are given for measuring the MOSFET subthreshold current-voltage characteristics and for the calculation of results.1.3 The application of this test method requires the MOSFET to have a substrate (body) contact.1.4 Both pre- and post-irradiation MOSFET subthreshold source or drain curves must follow an exponential dependence on gate voltage for a minimum of two decades of current.1.5 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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This PDF includes GI #2. 1. Scope 1.1 This Standard specifies procedures and requirements for Pure Tone Air Conduction Threshold Audiometry, without masking, used in hearing conservation programs. It is especially applicable to individuals whose he

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5.1 Digital integrated circuits are specified to operate with their inputs and outputs in either a logical 1 or a logical 0 state. The occurrence of signals having voltage levels not meeting the specifications of either of these levels (an upset condition) may cause the generation and propagation of erroneous data in a digital system.5.2 Knowledge of the radiation dose rate that causes upset in digital integrated circuits is essential for the design, production, and maintenance of electronic systems that are required to operate in the presence of pulsed radiation environments.1.1 This test method covers the measurement of the threshold level of radiation dose rate that causes upset in digital integrated circuits only under static operating conditions. The radiation source is either a flash X-ray machine (FXR) or an electron linear accelerator (LINAC).1.2 The precision of the measurement depends on the homogeneity of the radiation field and on the precision of the radiation dosimetry and the recording instrumentation.1.3 The test may be destructive either for further tests or for purposes other than this test if the integrated circuit being tested absorbs a total radiation dose exceeding some predetermined level. Because this level depends both on the kind of integrated circuit and on the application, a specific value must be agreed upon by the parties to the test (6.8).1.4 Setup, calibration, and test circuit evaluation procedures are included in this test method.1.5 Procedures for lot qualification and sampling are not included in this test method.1.6 Because of the variability of the response of different device types, the initial dose rate and device upset conditions for any specific test is not given in this test method but must be agreed upon by the parties to the test.1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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 and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 This practice provides one means for determining the scatter factors to establish either the safe-life, or inspection threshold, or recurring inspection intervals, or combinations thereof, as a result of aeroplane durability and damage tolerance assessments. This information can be used in conjunction with Specification F3115/F3115M.4.1.1 This practice defines scatter factors or factors to be used on the unfactored test or analytical mean lives, or both, for determining factored lives (that is, safe-life, inspection threshold, or recurring inspection intervals, or combinations thereof). These factors may be related to but are different from other factors such as load enhancement factor, and life factor that are used to compensate for long test duration. For guidance on life and load enhancement factors, refer to DOT/FAA/AR-10/6 or from relevant CAAs.4.1.2 The unfactored test or analytical mean life, or both, must be determined prior to the usage of this standard practice (see 4.5.1).4.2 The material presented herein is derived from the references listed in Section 2.4.3 Either the safe-life or inspection thresholds can be determined for the entire aeroplane or separately for components such as wing, empennage, landing gear, control surfaces, etc. Such determinations are based on test(s), similarity to previous test(s), or analysis supported by tests. Recurring inspection intervals are typically determined on the same basis but may also be supported by in-service data.4.4 The scatter factors described in this practice are applicable to cyclic test data that meets the following criteria:4.4.1 The cyclic test article must be representative of the production article. Careful consideration must be given for any modifications or alterations, or both, made to the test article prior to or during testing, or both, for metallic structures.4.4.2 At the completion of full-scale or component fatigue/cyclic tests (excluding landing gear), the residual strength capability must be demonstrated before determining either the safe-life, or inspection threshold.4.5 The following are not within the scope of this standard:4.5.1 Methodologies of durability, damage tolerance analysis, or test, or combinations thereof.4.5.2 Structures which use novel fabrication methods such as friction stir welding, additive manufacturing, and thermoplastic welding.4.5.3 Structural bonding (except already proven metal-to-metal bonding, etc.); for guidance on structural bonding refer to AC 20-107B (or AMC 20-29).4.6 The Finite Element Model (FEM) used for analysis must be validated with test data, or other independent analysis methods in accordance with relevant CAA requirements.4.7 The inspection intervals determined using this practice are independent of other inspection intervals that are defined by other process, such as Maintenance Steering Group (MSG).1.1 This practice provides guidance to determine scatter factors to establish either the safe-life, or inspection threshold, and inspection intervals to be published in the Airworthiness Limitation section of the maintenance manual in order to maintain continued airworthiness. The guidance materials presented herein for a means of compliance based on cyclic testing, damage tolerance testing, fatigue analysis, or damage tolerance analysis, or combinations thereof. The material was developed through open consensus of international experts in general aviation. The information was created by focusing on Levels 1, 2, 3 and 4 Normal Category aeroplanes. The content may be more broadly applicable; it is the responsibility of the applicant to substantiate broader applicability as a specific means of compliance.1.2 An applicant intending to propose this information as Means of Compliance for a design approval must seek guidance from their respective oversight authority (for example, published guidance from applicable civil aviation authorities, or CAAs) concerning the acceptable use and application thereof. For information on which oversight authorities have accepted this standard (whole or in part) as an acceptable Means of Compliance to their regulatory requirements (hereinafter “the Rules”), refer to the ASTM Committee F44 web page (www.astm.org/COMMITTEE/F44.htm).1.3 Units—This document may present information in either SI units, English Engineering units, or both; the values stated in each system may not be exact equivalents. Each system shall be used independently of the other; combining values from the two systems may result in nonconformance with the 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 Digital logic circuits are used in system applications where they are exposed to pulses of radiation. It is important to know the minimum radiation level at which transient failures can be induced, since this affects system operation.1.1 This guide is to assist experimenters in measuring the transient radiation upset threshold of silicon digital integrated circuits exposed to pulses of ionizing radiation greater than 103 Gy (matl.)/s.1.1.1 Discussion—This document is intended to be a guide to determine upset threshold, and is not intended to be a stand-alone document.1.2 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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5.1 The parameters KEAC or KIEAC determined by this test method characterize the resistance to crack growth of a material with a sharp crack in specific environments under loading conditions in which the crack-tip plastic region is small compared with the crack depth and the uncracked ligament. The less restrictive thickness requirements of KEAC are intended for those conditions in which the results are a strong function of the thickness of the specimen and the application requires the testing of specimens with thickness representative of the application. Since the chemical and mechanical influences cannot be separated, in some material/environment combinations, the thickness must be treated as a variable. A KEAC or KIEAC value is believed to represent a characteristic measurement of environment-assisted cracking resistance in a precracked specimen exposed to an environment under sustained tensile loading. A KEAC or KIEAC value may be used to estimate the relationship between failure stress and defect size for a material under any service condition, where the combination of crack-like defects, sustained tensile loading and the same specific environment would be expected to occur. (Background information concerning the development of this test method can be found in Refs (3-18). 5.1.1 The apparent KEAC or KIEAC of a material under a given set of chemical and electrochemical environmental conditions is a function of the test duration. It is difficult to furnish a rigorous and scientific proof for the existence of a threshold (4, 5). Therefore, application of KEAC or KIEAC data in the design of service components should be made with awareness of the uncertainty inherent in the concept of a true threshold for environment-assisted cracking in metallic materials (6, 18). A measured KEAC or KIEAC value for a particular combination of material and environment may, in fact, represent an acceptably low rate of crack growth rather than an absolute upper limit for crack stability. Care should be exercised when service times are substantially longer than test times. 5.1.2 The degree to which force deviations from static tensile stress will influence the apparent KEAC or KIEAC of a material is largely unknown. Small-amplitude cyclic loading, well below that needed to produce fatigue crack growth, superimposed on sustained tensile loading was observed to significantly lower the apparent threshold for stress corrosion cracking in certain instances (7, 8). Therefore, caution should be used in applying KEAC or KIEAC data to service situations involving cyclic loading. In addition, since this standard is for static loading, small-amplitude cyclic loading should be avoided during testing. 5.1.3 In some material/environment combinations, the smaller the specimen, the lower the measured KEAC value, while in other material/environment combinations the measured KIEAC value will be the lowest value (5, 9, 10, 11, 12). If, for the material/environment combination of interest, it is not known which specimen size will result in the lower measured value, then it is suggested that the use of both specimen sizes should be considered; that is, specimens with thicknesses representative of the application and specimens in which the thickness meets the requirements (see 7.2.1) of a KIEAC value. 5.1.3.1 The user may optionally determine and report a KEAC value or a KIEAC value. The specimen size validity requirements for a KEAC value meet the size requirements developed for Test Method E647 to achieve predominately elastic behavior in the specimen. Test Method E647 size requirements for compact specimens should be applied to both the compact specimen and the beam specimen. The specimen size validity requirements for a KIEAC value meet the size requirements developed for plane strain conditions for Test Method E399. 5.1.4 Evidence of environment-assisted crack growth under conditions that do not meet the validity requirements of 7.2 may provide an important indication of susceptibility to environmental cracking but cannot be used to determine a valid KEAC value (14). 5.1.5 Environment-assisted cracking is influenced by both mechanical and electrochemical driving forces. The latter can vary with crack depth, opening, or shape and may not be uniquely described by the fracture mechanics stress intensity factor. As an illustrative example, note the strong decrease reported in KISCC5 with decreasing crack size below 5 mm for steels in 3 % NaCl in water solution (15) . Geometry effects on K similitude should be experimentally assessed for specific material/environment systems. Application modeling based on KEAC similitude should be conducted with caution when substantial differences in crack and specimen geometry exist between the specimen and the component. 5.1.6 Not all combinations of material and environment will result in environment-assisted cracking. In general, susceptibility to aqueous stress-corrosion cracking decreases with decreasing material strength level. When a material in a certain environment is not susceptible to environment-assisted cracking, it will not be possible to measure KEAC or KIEAC. This method can serve the following purposes: 5.1.6.1 In research and development, valid KEAC or KIEAC data can quantitatively establish the effects of metallurgical and environmental variables on the environment-assisted cracking resistance of materials. 5.1.6.2 In service evaluation, valid KEAC or KIEAC data can be utilized to establish the suitability of a material for an application with specific stress, flaw size, and environmental conditions. 5.1.6.3 In acceptance and quality control specifications, valid KEAC or KIEAC data can be used to establish criteria for material processing and component inspection. 5.1.7 Test results will be affected by force relaxation in constant displacement bolt-loaded compact specimens for some material/environment conditions. For relatively low strength material, non-agressive environments, or high test temperatures, force relaxation can occur independently from environment-assisted cracking. Significant force relaxation would make cracking results difficult to interpret. If force relaxation is suspected of influencing the data, the following trial specimen test is recommended. Test a trial specimen with all the test conditions of interest, except with no environment applied. Monitor the force on the sample using a bolt with an electronic load cell attached. Instrumented bolts of this type are commercially available. A force relaxation of more than 5 % after 24 h indicates that the constant displacement test method may not be suitable for these test conditions, and a constant force test should be considered. 5.1.8 Residual stresses can have an influence on environment-assisted cracking. The effect can be significant when test specimens are removed from material in which complete stress relief is impractical, such as weldments, as-heat-treated materials, complex wrought parts, and parts with intentionally produced residual stresses. Residual stresses superimposed on the applied stress can cause the local crack-tip stress-intensity factor to be different from that calculated from externally applied forces or displacements. Irregular crack growth during precracking, such as excessive crack front curvature or out-of-plane crack growth, often indicates that residual stresses will affect the subsequent environment-assisted crack growth behavior. Changes in the zero-force value of crack-mouth-opening displacement as a result of precrack growth is another indication that residual stresses will affect the subsequent environment-assisted crack growth. 5.1.9 For bolt loaded specimens, the user should realize that material being tested at an non-ambient temperature may have a different displacement-to-force ratio from that at ambient temperature, and also the bolt material may have a different coefficient of thermal expansion from that of the material being tested. Care should be taken to minimize these effects. 1.1 This test method covers the determination of the environment-assisted cracking threshold stress intensity factor parameters, KIEAC and KEAC, for metallic materials from constant-force testing of fatigue precracked beam or compact fracture specimens and from constant-displacement testing of fatigue precracked bolt-load compact fracture specimens. 1.2 This test method is applicable to environment-assisted cracking in aqueous or other aggressive environments. 1.3 Materials that can be tested by this test method are not limited by thickness or by strength as long as specimens are of sufficient thickness and planar size to meet the size requirements of this test method. 1.4 A range of specimen sizes with proportional planar dimensions is provided, but size may be variable and adjusted for yield strength and applied force. Specimen thickness is a variable independent of planar size. 1.5 Specimen configurations other than those contained in this test method may be used, provided that well-established stress intensity calibrations are available and that specimen dimensions are of sufficient size to meet the size requirements of this test method during testing. 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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