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4.1 The axial force fatigue test is used to determine the effect of variations in material, geometry, surface condition, stress, and so forth, on the fatigue resistance of metallic materials subjected to direct stress for relatively large numbers of cycles. The results may also be used as a guide for the selection of metallic materials for service under conditions of repeated direct stress.4.2 In order to verify that such basic fatigue data generated using this practice is comparable, reproducible, and correlated among laboratories, it may be advantageous to conduct a round-robin-type test program from a statistician's point of view. To do so would require the control or balance of what are often deemed nuisance variables; for example, hardness, cleanliness, grain size, composition, directionality, surface residual stress, surface finish, and so forth. Thus, when embarking on a program of this nature it is essential to define and maintain consistency a priori, as many variables as reasonably possible, with as much economy as prudent. All material variables, testing information, and procedures used should be reported so that correlation and reproducibility of results may be attempted in a fashion that is considered reasonably good current test practice.4.3 The results of the axial force fatigue test are suitable for application to design only when the specimen test conditions realistically simulate service conditions or some methodology of accounting for service conditions is available and clearly defined.1.1 This practice covers the procedure for the performance of axial force controlled fatigue tests to obtain the fatigue strength of metallic materials in the fatigue regime where the strains are predominately elastic, both upon initial loading and throughout the test. This practice is limited to the fatigue testing of axial unnotched and notched specimens subjected to a constant amplitude, periodic forcing function in air at room temperature.1.2 The use of this test method is limited to specimens and does not cover testing of full-scale components, structures, or consumer products.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 The text of this standard references notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.NOTE 1: The following documents, although not directly referenced in the text, are considered important enough to be listed in this practice:E739 Practice for Statistical Analysis of Linear or Linearized Stress-Life (S-N) and Strain-Life (ε-N) Fatigue DataSTP 566 Handbook of Fatigue Testing2STP 588 Manual on Statistical Planning and Analysis for Fatigue Experiments3STP 731 Tables for Estimating Median Fatigue Limits41.5 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 It is well understood how to measure the forces applied to a specimen under static conditions. Practices E4 details the required process for verifying the static force measurement capabilities of testing machines. During dynamic operation however, additional errors may manifest themselves in a testing machine. Further verification is necessary to confirm the dynamic force measurement capabilities of testing machines.NOTE 1: The static machine verification accomplished by Practices E4 simply establishes the reference. Indicated forces measured from the force cell are compared with the dynamometer conditioned forces statically for confirmation and then dynamically for dynamic verification of the fatigue testing system's force output.NOTE 2: The dynamic accuracy of the force cell's output will not always meet the accuracy requirement of this standard without correction. Dynamic correction to the force cell output can be applied provided that verification is performed after the correction has been applied.NOTE 3: Overall test accuracy is a combination of measurement accuracy and control accuracy. This practice provides methods to evaluate either or both. As control accuracy is dependent on many more variables than measurement accuracy it is imperative that the test operator utilize appropriate measurement tools to confirm that the testing machine’s control behavior is consistent between verification activities and actual testing activities.4.2 Dynamic errors are primarily span dependent, not level dependent. That is, the error for a particular force endlevel during dynamic operation is dependent on the immediately preceding force endlevel. Larger spans imply larger absolute errors for the same force endlevel.4.3 Due to the many test machine factors that influence dynamic force accuracy, verification is recommended for every new combination of potential error producing factors. Primary factors are specimen design, machine configuration, test frequency, and loading span. Clearly, performing a full verification for each configuration is often impractical. To address this problem, dynamic verification is taken in two parts.4.3.1 First, one or more full verifications are performed at least annually. The main body of this practice describes that procedure. This provides the most accurate estimate of dynamic errors, as it will account for electronic as well as acceleration-induced sources of error.4.3.2 The second part, described in Annex A1, is a simplified verification procedure. It provides a simplified method of estimating acceleration-induced errors only. This procedure is to be used for common configuration changes (that is, specimen/grip/crosshead height changes).4.4 Dynamic verification of the fatigue system is recommended over the entire range of force and frequency over which the planned fatigue test series is to be performed. Endlevels are limited to the machine's verified static force as defined by the current static force verification when tested in accordance with Practices E4.NOTE 4: There is uncertainty as to whether or not the vibration in a frame will be different when operating in compression as opposed to tension. As a consequence, this practice recommends performing verifications at maximum tension and maximum compression endlevels. The total span does not need to be between those two levels, but can be performed as two tests.NOTE 5: Primary electronic characteristics affecting dynamic measurement accuracy are noise and bandwidth. Excessive noise is generally the dominant effect at the minimum test frequency. Insufficient bandwidth-induced errors are generally most significant at the maximum test frequency.1.1 This practice covers procedures for the dynamic verification of cyclic force amplitude control or measurement accuracy during constant amplitude testing in an axial fatigue testing system. It is based on the premise that force verification can be done with the use of a strain gaged elastic element. Use of this practice gives assurance that the accuracies of forces applied by the machine or dynamic force readings from the test machine, at the time of the test, after any user applied correction factors, fall within the limits recommended in Section 9. It does not address static accuracy which must first be addressed using Practices E4 or equivalent.1.2 Verification is specific to a particular test machine configuration and specimen. This standard is recommended to be used for each configuration of testing machine and specimen. Where dynamic correction factors are to be applied to test machine force readings in order to meet the accuracy recommended in Section 9, the verification is also specific to the correction process used. Finally, if the correction process is triggered or performed by a person, or both, then the verification is specific to that individual as well.1.3 It is recognized that performance of a full verification for each configuration of testing machine and specimen configuration could be prohibitively time consuming and/or expensive. Annex A1 provides methods for estimating the dynamic accuracy impact of test machine and specimen configuration changes that may occur between full verifications. Where test machine dynamic accuracy is influenced by a person, estimating the dynamic accuracy impact of all individuals involved in the correction process is recommended. This practice does not specify how that assessment will be done due to the strong dependence on owner/operators of the test machine.1.4 This practice is intended to be used periodically. Consistent results between verifications is expected. Failure to obtain consistent results between verifications using the same machine configuration implies uncertain accuracy for dynamic tests performed during that time period.1.5 This practice addresses the accuracy of the testing machine's force control or indicated forces, or both, as compared to a dynamometer's indicated dynamic forces. Force control verification is only applicable for test systems that have some form of indicated force peak/valley monitoring or amplitude control. For the purposes of this verification, the dynamometer's indicated dynamic forces will be considered the true forces. Phase lag between dynamometer and force transducer indicated forces is not within the scope of this practice.1.6 The results of either the Annex A1 calculation or the full experimental verification must be reported per Section 10 of this standard.1.7 This practice provides no assurance that the shape of the actual waveform conforms to the intended waveform within any specified tolerance.1.8 This standard is principally focused at room temperature operation. It is believed there are additional issues that must be addressed when testing at high temperatures. At the present time, this standard practice must be viewed as only a partial solution for high temperature testing.1.9 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard.1.10 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.1.11 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 Fatigue test results may be significantly influenced by the properties and history of the parent material, the operations performed during the preparation of the fatigue specimens, and the testing machine and test procedures used during the generation of the data. The presentation of fatigue test results should include citation of basic information on the material, specimens, and testing to increase the utility of the results and to reduce to a minimum the possibility of misinterpretation or improper application of those results.1.1 This practice covers the desirable and minimum information to be communicated between the originator and the user of data derived from constant-force amplitude axial, bending, or torsion fatigue tests of metallic materials tested in air and at room temperature.NOTE 1: Practice E466, although not directly referenced in the text, is considered important enough to be listed in this standard.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.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 This test method covers one procedure for determining fatigue life at various extension-ratios. The strain cycle is characteristic of the type of test apparatus specified. Experience in fatigue testing shows that fatigue life may have a wide, non-normal distribution and, therefore, a large standard deviation that is compound dependent. Natural rubber, for example, has shown a narrower distribution than many synthetic rubbers. A large number of specimens may, therefore, be required to yield the desired precision. Comparison of different rubber compounds should be made with due consideration to the standard deviation for each (see 7.1).5.2 Fatigue data, as generated in this test method, give primarily an estimate of the crack initation behavior of a rubber vulcanizate and only a very approximate measure of the crack propagation rate. The information obtained may be useful in predicting the flex-life performance of a compound in active service; however, the user should be aware that in actual use, products are subjected to many other fatigue factors not measured in this test method.1.1 This test method covers the determination of fatigue life of rubber compounds undergoing a tensile-strain cycle. During part of the cycle, the strain is relaxed to a zero value. The specimens are tested without intentionally initiated flaws, cuts, or cracks. Failure is indicated by a complete rupture of the test specimen.1.2 No exact correlation between these test results and service is given or implied. This is due to the varied nature of service conditions. These test procedures do yield data that can be used for the comparative evaluation of rubber compounds for their ability to resist (dynamic) extension cycling fatigue.1.3 The values stated in SI units are to be regarded as standard. The values given 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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5.1 Clinical fractures of total knee femoral components have been observed and reported in the literature (1-12).4 (See X1.4.)5.2 This test method provides a procedure to perform fatigue testing on total knee femoral components under closing conditions caused by an unsupported condyle that result in a tensile stress on the articular surface and a compressive stress on the interior, beveled surfaces.5.3 This test method is intended to evaluate the fatigue performance of knee femoral components under a simulated articulation loading condition. The load acts to move the posterior femoral condyle toward the anterior flange.5.4 This test method simulates a clinically severe condition in which all bony support is lost and one condyle is supporting the complete load at the knee joint at 90° of tibiofemoral flexion.5.5 Testing in accordance with this test method typically produces regions of high tensile stress in the intercondylar notch and on the articular surface where the anterior flange transitions to condyle.5.6 The loading of total knee femoral components using this test method may differ from actual in vivo loading conditions. The results obtained here cannot be used to directly predict in vivo performance. However, this test method is designed to enable comparison between the fatigue performance of different total knee femoral component designs when tested under similar closing conditions.1.1 This standard applies to metallic total knee femoral components used in total knee arthroplasty (TKA). Femoral components made of nonmetallic materials (for example, ceramic, polymer) could possibly be evaluated using this test method. However, such materials may include risks of new failure mechanisms which are not considered in this test method.1.2 The procedure described in this standard is performed on total knee femoral components for supporting determination of fatigue behavior under closing-style loading conditions. Closing-style loading refers to forces that act to reduce the femoral intercondylar depth, resulting in a tensile stress on the articular surface of the femoral condyle. (See 3.2.2.)1.3 Different designs can be characterized as, but not limited to, posterior cruciate ligament retaining (CR), posterior stabilizing (PS), and revision.1.4 This standard does not address evaluation of femoral components under opening-style loading conditions which have also generated clinical failures. Under opening-style loading conditions, forces are applied to the inner contour of the femoral component in a way that the forces act to increase the intercondylar depth, or open the femoral component.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 Use of this Methodology: 5.1.1 This guide provides a compendium of information on methods to use fracture data, fatigue life models, and statistical techniques to estimate the structural fatigue durability of an implantable medical device under anticipated in vivo loading modes. The methodology for high-cycle fatigue assessment relies on hyper-physiological tests intended to cause device fractures. Using the FtF methodology, fractures should not be avoided during testing; instead they provide the information required to statistically assess device longevity under a wide variety of physiological and hyper-physiological test conditions.5.1.2 Through evaluation of fracture locations, the geometries after fractures, and the use conditions of the device, this guide may be used to help assess device safety.5.1.3 This guide may be used to help assess differences in fatigue life between different devices or device histories. The effects on fatigue life due to changes to a device’s geometry, processing, or material may be assessed using this guide.5.1.4 Users of this guide must keep in mind that bench tests are simulations of in-use conditions. Adherence to this guide may not guarantee that results translate to individual clinical scenarios. Therefore, in assessing a device’s fatigue performance, the results from Fatigue to Fracture testing should be reviewed in combination with other available data, such as animal studies, clinical experience, and computational simulations.5.2 Significance of this Methodology: 5.2.1 While the FtF methodology applies only to bench tests, it can provide insights into device behavior that would not necessarily be apparent in clinical studies that typically focus on patient outcomes. After appropriate boundary conditions such as loadings, fixturing, and materials have been determined, the FtF methodology can provide extensive information on the expected longevity of a device in a period 10 to 1000 times shorter than a real-time clinical study.5.2.2 FtF is informative in characterizing device behavior over a wide range of loads and cycles. This is especially valuable when the in vivo loading mode is understood but the load magnitude and cycle requirements are not well known or when characterizing device performance over a wide range of patient lifetimes, activity levels, and physiological states is desired.5.2.3 In FtF, test loads greater than the devices’ expected use conditions are used. Thus, factors of safety can be measured relative to expected in vivo use conditions in both loading/deformation severity and number of cycles.5.2.4 In FtF, the nature and location of fractures observed as a function of load can help provide insights into the device response to the applied loading. The identified primary and follow-on fracture locations and modes may be used to assess the credibility of device computational models, as well as to evaluate potential impacts on clinical safety and efficacy, especially post-fracture.5.2.5 The FtF methodology can quickly and reliably assess the impact of changes in processes, materials, or small changes in geometry on in vitro fatigue life. These assessments with respect to fracture can be quantified and used as part of validating design changes, demonstrating that the device meets product specifications, or as part of guiding design improvements.5.2.6 FtF testing can often be completed in a shorter period of time than test-to-success testing since the FtF tests are typically terminated at a smaller number of cycles. Specifically, when extrapolation in cycles is appropriate, comparisons of the loads or the frequency of fracture at a lower number of cycles can provide a useful measure of equivalence.1.1 This guide is intended to provide an experimental methodology to assess and determine the structural fatigue life of implantable cardiovascular medical devices.1.2 This guide is also intended to provide methodologies to determine statistical bounds on fatigue life at in vivo use conditions using measured fatigue life derived in whole or in part from hyper-physiological testing to fracture.1.3 This guide may be used to assess or characterize device durability during design development and for testing to device product specifications.1.4 Fretting, wear, creep-fatigue, and absorbable materials are outside the scope of this guide, though elements of this guide may be applicable.1.5 As a guide, this document provides direction but does not recommend a specific course of action. It is intended to increase the awareness of information and approaches. This guide is not a test method. This guide does not establish a standard practice to follow in all cases.1.6 This guide is meant as a complement to other regulatory and device-specific guidance documents or standards and it does not supersede the recommendations or requirements of such documents.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.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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This practice can be used to describe the effects of materials, manufacturing, and design variables on the fatigue resistance of metallic stemmed femoral components subjected to cyclic loading for relatively large numbers of cycles. The recommended test assumes a “worst case” situation where proximal support for the stem has been lost. It is also recognized that for some materials the environment may have an effect on the response to cyclic loading. The test environment used and the rationale for the choice of that environment should be described in the report. It is recognized that actual in vivo loading conditions are not ofconstant amplitude. However, there is not sufficient information available to create standard load spectrums for metallic stemmed femoral components. Accordingly, a simple periodic constant amplitude force is recommended. In order for fatigue data on femoral stems to be useful for comparison, it must be reproducible among different laboratories. Consequently, it is essential that uniform procedures be established.1.1 This practice describes a method for the fatigue testing of metallic stemmed femoral components used in hip arthroplasty. The described method is intended to be used to evaluate the comparison of various designs and materials used for stemmed femoral components used in the arthroplasty. This practice covers procedures for the performance of fatigue tests using (as a forcing function) a periodic constant amplitude force. 1.2 This practice applies primarily to one-piece prostheses and modular components, with head in place such that prostheses should not have an anterior/posterior bow, and should have a nearly straight section on the distal 50 mm of the stem. This practice may require modifications to accommodate other femoral stem designs. 1.3 The values stated in SI units are to be regarded as the standard. 1.4 For additional information see Refs. (1-5) .

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5.1 This in-vitro test method includes the use of cyclic forces to evaluate the fatigue strength of acetabular shells or monoblock acetabular devices used in THR.5.2 Fracture or cracking of acetabular shells or monoblock acetabular devices in THR, although rare, does occur.1.1 This test method is intended to evaluate the fatigue strength of metallic acetabular shells with hemispheric outer surfaces.1.2 This test method, as described, is not intended to evaluate the following: the strength of components that may be mated with the acetabular shells (for example, augments, acetabular liners); attributes of the shells not related to strength (for example, fixation, coating adhesion); the strength of acetabular shell features away from, or loaded differently than, the primary load bearing region of the shell (for example, screws, spikes, flanges); non-hemispherical shells (for example, patient-matched geometries); or corrosion between modular components.1.3 Modifications to this test method (for example, different support medium, different size/position of unsupported region, different testing environment) may result in a method appropriate to evaluate the characteristics listed in 1.2. Such modification must have adequate justification.1.4 Although the methodology described does not replicate all physiological force conditions, it is a means of in vitro comparison of acetabular device designs under repeated forces.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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1.1 This test method covers the determination of the effect of repetitions of the same magnitude of flexural stress on plastics by fixed-cantilever type testing machines, designed to produce a constant-amplitude-of-force on the test specimen each cycle. 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 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 practice can be used to describe the effects of materials, manufacturing, and design variables on the fatigue resistance of metallic stemmed femoral components subjected to cyclic loading for relatively large numbers of cycles. The recommended test assumes a worst case situation in which proximal support for the stem has been lost. It is also recognized that, for some materials, the environment has an effect on the response to cyclic loading (see 12.7). The test environment used and rationale for the choice of that environment should be described in the test report.It is recognized that actual in vivo loading conditions are not constant amplitude. However, sufficient information is not available to create standard load spectrums for metallic stemmed femoral components. A simple periodic constant amplitude force is accordingly recommended.1.1 This practice covers a method for the fatigue testing of metallic stemmed femoral components used in hip arthroplasty. The described method is intended to be used for evaluation in comparisons of various designs and materials used for stemmed femoral components used in the arthroplasty. This practice covers procedures for the performance of fatigue tests using (as a forcing function) a periodic constant amplitude force.1.2 This practice applies primarily to one-piece prostheses and femoral stems with modular heads, with the head in place. Such prostheses should not have an anterior-posterior A-P bow or a medial-lateral M-L bow, and they should have a nearly straight section on the distal 50 mm of the stem. This practice may require modifications to accommodate other femoral stem designs.1.3 The values stated in SI units are to be regarded as the standard.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 While this test method is intended for use in metal-to-metal applications it may be used for measuring the fatigue properties of adhesives using plastic adherends, provided consideration is given to the thickness of the plastic adherends. Doublers may be required for plastic adherends to prevent bearing failure in the adherends.4.2 A variation in the thickness of the adherends can influence the test results. For this reason, the thickness of the sheets used to make the test specimens should be specified in the material specification. When no thickness is specified, metal adherends 1.63 mm (0.064 in.) thick are recommended.1.1 This test method covers the measurement of fatigue strength in shear by tension loading of adhesives on a standard specimen and under specified conditions of preparation, loading, and testing.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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4.1 Materials scientists and engineers are making increased use of statistical analyses in interpreting S-N and ε-N fatigue data. Statistical analysis applies when the given data can be reasonably assumed to be a random sample of (or representation of) some specific defined population or universe of material of interest (under specific test conditions), and it is desired either to characterize the material or to predict the performance of future random samples of the material (under similar test conditions), or both. 1.1 This guide covers only S-N and ε-N relationships that may be reasonably approximated by a straight line (on appropriate coordinates) for a specific interval of stress or strain. It presents elementary procedures that presently reflect good practice in modeling and analysis. However, because the actual S-N or ε-N relationship is approximated by a straight line only within a specific interval of stress or strain, and because the actual fatigue life distribution is unknown, it is not recommended that (a) the S-N or ε-N curve be extrapolated outside the interval of testing, or (b) the fatigue life at a specific stress or strain amplitude be estimated below approximately the fifth percentile (P ≃ 0.05). As alternative fatigue models and statistical analyses are continually being developed, later revisions of this guide may subsequently present analyses that permit more complete interpretation of S-N and ε-N data. 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 This test method can be used to describe the effects of materials, manufacturing, and design variables on the fatigue performance of metallic tibial trays subject to cyclic loading for relatively large numbers of cycles.4.2 The loading of tibial tray designs in vivo will, in general, differ from the loading defined in this practice. The results obtained here cannot be used to directly predict in vivo performance. However, this practice is designed to allow for comparisons between the fatigue performance of different metallic tibial tray designs, when tested under similar conditions.4.3 In order for fatigue data on tibial trays to be comparable, reproducible, and capable of being correlated among laboratories, it is essential that uniform procedures be established.1.1 This test method covers a procedure for the fatigue testing of metallic tibial trays used in partial knee joint replacements.1.2 This test method covers the procedures for the performance of fatigue tests on metallic tibial components using a cyclic, constant-amplitude force. It applies to tibial trays which cover either the medial or the lateral plateau of the tibia.1.3 This test method may require modifications to accommodate other tibial tray designs.1.4 This test method is intended to provide useful, consistent, and reproducible information about the fatigue performance of metallic tibial trays with unsupported mid-section of the condyle.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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5.1 The bending fatigue test described in this test method provides information on the ability of a copper alloy flat sheet and strip of spring material to resist the development of cracks or general mechanical deterioration as a result of a relatively large number of cycles (generally in the range 105 to 108) under conditions of constant displacement.5.2 This test method is primarily a research and development tool which may be used to determine the effect of variations in materials on fatigue strength and also to provide data for use in selecting copper alloy spring materials for service under conditions of repeated strain cycling.5.3 The results are suitable for direct application in design only when all design factors such as loading, geometry of part, frequency of straining, and environmental conditions are known. The test method is generally unsuitable for an inspection test or a quality control test due to the amount of time and effort required to collect the data.1.1 This test method establishes the requirements for the determination of the reversed or repeated bending fatigue properties of copper alloy flat sheet or strip of spring materials by fixed cantilever, constant deflection (that is, constant amplitude of displacement)-type testing machines. This method is limited to flat sheet or strip ranging in thickness from 0.005 in. to 0.062 in. (0.13 mm to 1.57 mm), to a fatigue life range of 105 to 108 cycles, and to conditions where no significant change in stress-strain relations occurs during the test.NOTE 1: This implies that the load-deflection characteristics of the material do not change as a function of the number of cycles within the precision of measurement. There is no significant cyclic hardening or softening.1.2 Units—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.1.3 The following safety hazard caveat pertains only to the test methods(s) described in this test method.1.3.1 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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4.1 Because of wide variations in service conditions, no correlation between these accelerated tests and service performance is given or implied. However, the test methods yield data that can be used to estimate relative service quality of different compounds. They are often applicable to research and development studies.1.1 These test methods may be used to compare the fatigue characteristics and rate of heat generation of different rubber vulcanizates when they are subjected to dynamic compressive strains.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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