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Miniature specimen testing techniques are used to characterize the mechanical behavior of UHMWPE stock materials and surgical implants after manufacture, sterilization, shelf aging, radiation crosslinking, thermal treatment, and implantation (1). Furthermore, experimental UHMWPE materials can be evaluated after accelerated aging and hip or knee wear simulation. Consequently, the small punch test makes it possible to examine relationships between wear performance and mechanical behavior of UHMWPE. This test method can also be used to rank the mechanical behavior of UHMWPE relative to a reference control material (such as the NIST Ultra-High Molecular Weight Polyethylene Reference Material #8456).Small punch testing results may vary with specimen preparation and with the speed and environment of testing. Consequently, where precise comparative results are desired, these factors must be carefully controlled.1.1 This test method covers the determination of mechanical behavior of ultra-high molecular weight polyethylene (UHMWPE) by small punch testing of miniature disk specimens (0.5 mm in thickness and 6.4 mm in diameter). The test method has been established for characterizing UHMWPE surgical materials after ram extrusion or compression molding (1,2) ; for evaluating as-manufactured implants after radiation crosslinking and sterilization (3,4); as well as for testing of implants that have been retrieved (explanted) from the human body (5,6).1.2 The parameters of the small punch test, namely the peak load, ultimate displacement, ultimate load, and work to failure, provide metrics of the yielding, ultimate strength, ductility, and toughness of UHMWPE under multiaxial loading conditions. Because the mechanical behavior of UHMWPE is different when loaded under uniaxial and multiaxial loading conditions (3), the small punch test provides a complementary mechanical testing technique to the uniaxial tensile testing specified for medical grade UHMWPE by Specification F 648.1.3 In addition to its use as a research tool in implant retrieval analysis, the small punch test can be used as a laboratory screening test to evaluate new UHMWPE materials, such as those created by gamma or electron beam irradiation (1). The test method is also well suited for characterization of UHMWPE before and after accelerated aging (for example, Guide F 2003), and in that regard it can provide ranking of the mechanical degradation of different UHMWPE samples after oxidative degradation (4,7).1.4 The small punch test has been applied to other polymers, including polymethyl methacrylate (PMMA) bone cement, polyacetal, and high density polyethylene (HDPE) (8,9). However, the small punch testing of polymers other than UHMWPE is beyond the scope of this standard.1.5 The values stated in SI units are to be regarded as standard. The units in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered 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 and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 The induction period may be used as an indication of the oxidation and storage stability of middle distillate fuel.5.2 Compared to some other oxidation and storage stability test methods, this method uses a small sample and gives a result in a short time period.1.1 This laboratory test method covers a quantitative determination of the stability of middle distillate fuels such as diesel fuels and heating oils, with up to 100 % biodiesel, under accelerated oxidation conditions, by an automatic instrument.NOTE 1: This test method is technically equivalent to test method EN 160911.2 This test method is designed for products complying with Specification D975 on Diesel Fuel, Grades No. 1D and 2D; Specification D396 on Burner Fuel, Grades No. 1 and No. 2; Specification D6751 on Biodiesel, B100, and Specification D7467 on Diesel Fuel Oil, B6 to B20.1.3 This test method measures the induction period, under specified conditions, which can be used as an indication of the oxidation and storage stability of middle distillate fuels.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 The test method is intended to be used by sUAS manufacturers, sUAS operators, and CAAs to assess the safety of sUA impacts to people on the ground during operations involving flight over people.5.2 The test method provides a framework for creating new designs and evaluating existing designs to determine the sUA’s blunt force trauma injury potential to the head or neck, or both, during a collision with a person on the ground.5.3 Applicants can determine whether to use Methods A, B, C, or D based upon their specific sUA characteristics, flight operations, and CAA requirements. In some cases, sUA with low impact KE below 54 ft-lbf [73 J] may not require rigorous testing to ensure safety to the nonparticipating public and can use Method A. Vehicles with higher impact KEs should conduct impact testing using Method B, Method C, or Method D. Method B is simpler than Method C and, therefore, less costly for the applicant. Method B results may be more conservative since the test setup is more rigid and can result in an increase in the amount of energy transferred during the impact than the injury metrics established using a full ATD. Method C testing is costlier and schedule-intensive, but provides a higher level of certainty of the injury potential of the sUA and is more directly comparable to established automotive injury metrics and injury metrics derived from ATD testing and used by the governing CAA. Method D allows for the direct comparison to energy-based requirement of some CAAs.5.4 The output of Method A is a verification that the sUA or sUA with mitigation does not exceed the 54 ft-lbf impact KE throughout its flight envelope based upon flight test data as means of obtaining approval for flight over people for Category 2 or 3 operations for the FAA. Other governing CAAs may only require a weight metric or other impact energy metric in lieu of the 54 ft-lbf impact KE.5.5 The output from Methods B and C is a characterization of the forces (measured in acceleration of the head form or ATD) expected during an MPWC head impact as a function of sUA KE. For Method B, this result is compared to the minimum impact energy resulting in a skull fracture based solely upon peak acceleration to determine the impact KE associated with this injury based upon energy transfer. Method C testing is more rigorous and may be correlated to other standards for both head and neck injury (such as the FMVSS 208 or other automotive standards) to determine whether the sUA is sufficiently safe to operate in Category 2 and 3 Operations.8 By evaluating sUA KE in the MPWC orientation and a variety of ATD impacts, the applicant should assess the sUA for injury potential using the governing CAA injury thresholds. The limiting impact KE may establish the operational limits that correspond to that specific value. This test method proposes the use of the standards called out in the ASSURE impact tests conducted as part of Task A14.95.6 The output from Method D is a verification that the sUA does not exceed the comparison metrics associated with the transfer of energy resulting from the impact of a rigid object at a specified impact KE for the rigid impactor. The impact KE of the rigid impactor is determined by the CAA for different categories of operations over people. For example, an sUA meets this standard if its impact test results are lower than the rigid object test results.5.7 Outputs from Methods A, B, C, and D may be used in conjunction with governing CAA’s metrics for certifying the sUA for flight over people.1.1 This test method is applicable to small unmanned aircraft (sUA) that are limited in the United States in accordance with 14 CFR § 107.3 to be less than 55 lbf. The test method provides a standardized method for assessing the safety of sUA impacts with a person on the ground. Results from testing using Methods A, B, C, or D are intended to be used to support an applicant in obtaining permission from the governing Civil Aviation Authority (CAA) for flight over people. Approval of reports for the conduct of tests and the decision to grant permission rests with the governing CAA based upon adherence to the methodologies outlined in this test method.1.2 This test method is based on methods researched by the FAA Center of Excellence for Unmanned Aircraft Systems (UAS) supported by the Alliance for System Safety of UAS through Research Excellence (ASSURE). These methods expand on extensive research and testing conducted by the automotive industry to support quantitative automotive passenger safety standards and testing and test data on sUA collected by ASSURE.1.3 The purpose of this test method is to define a method to establish confidence in the overall injury potential of a particular sUA configuration under probable failure conditions. This testing is not meant to simulate the worst possible impact for the most conservative set of the population. It is expected that CAAs should determine what injury thresholds are acceptable under their public policy and determine operational limitations for various operations by using the data from this testing in conjunction with the specific concept of operations proposed by the applicant.1.4 The test method provides four methods for evaluating the potential for impact injury: a simple analytical method, a simplified test, a more rigorous test, and a test method normed to approximate energy transfer values with appropriate safety margins applied to each approach to address uncertainty in each of the approaches.1.5 The applicant should understand the actual operating characteristics of their sUA before starting the process outlined in this test method. It is assumed that the applicant is able to substantiate the most probable, worst-case (MPWC) impact orientation of the sUA; typical and maximum operating heights and speeds; and terminal velocity of their sUA as a function of altitude to compare the results of the impact analysis with the proposed operation for the sUA. This test method is intended to supplement the verification requirements of Specification F3298 and Specification F3322, as well as a supplement to Specification F2910. This test method should not be used as a stand-alone document without consideration of other ASTM UAS standards.1.6 These methods assume that a blunt force head impact is the most likely injury mechanism leading to serious injury or fatalities. The level of blunt force injury to the head may be adjusted for various applications (such as sUA operations around first responders with helmets) and compared with the amount of force or load factor that the sUA transfers during a collision.1.7 Method B is not appropriate for foam-built fixed-wing sUA due to the stiffness of the FAA Hybrid III ATD Head and Neck. Until a different impactor can be developed for Method B, these sUA should use Method C or D for evaluation.1.8 Units—The values stated in either International System (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.1.9 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.10 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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3.1 A number of laboratory procedures are used to evaluate the effectiveness of fire-retardant and fire-resistant treatments and coatings. In general, these methods measure the three stages of fire development: (1) ignition; (2) flame spread (rate of growth of the fire); and (3) conflagration extent. While all three are of extreme importance, flame spread has been recognized as the main factor associated with testing fire-retardant coatings.3.2 Flame spread ratings based upon Test Method E84 have acquired common acceptance by regulatory agencies, but such large-scale tests are seldom practical during the development or modification of a fire-retardant coating.3.3 This test method provides the relative flame spread of experimental coatings using small test specimens under the conditions established in the 2-foot tunnel. By experimentally calibrating the 2-foot tunnel with similar Test Method E84-rated fire-retardant paint, results obtained by this test method can be used to screen coatings for suitability for testing in the Test Method E84 tunnel.3.3.1 This test method is intended as an experimental tool in evaluating experimental coatings for further development. No direct correlation of results from this test method and the Test Method E84 tunnel have been made or are implied.3.3.2 The results obtained by this test method do not in themselves act as an accurate predictor of performance in Test Method E84 and shall not be used for the purpose of certification to any class of flame spread performance.1.1 This test method determines the protection a coating affords its substrate, and the comparative burning characteristics of coatings by evaluating the flame spread over the surface when ignited under controlled conditions in a small tunnel. This establishes a basis for comparing surface-burning characteristics of different coatings without specific consideration of all the end-use parameters that might affect surface-burning characteristics under actual fire conditions.1.2 In addition to the experimental flame spread rate, the weight of panel consumed, time of afterflaming and afterglow, char dimensions and index, and height of intumescence can be measured in this test. However, a relationship should not be presumed among these measurements.1.3 This standard is used to determine certain fire-test responses of materials, products, or assemblies to heat and flame under controlled conditions by using results obtained from fire-test response standards. The results obtained from using this standard do not by themselves constitute measures of fire hazard or fire risk.1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.5 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.1.6  Fire testing is inherently hazardous. Adequate safeguards for personnel and property shall be employed in conducting these tests.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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5.1 Test Methods A, B, and C provide a means of evaluating the tensile modulus of geogrids and geotextiles for applications involving small-strain cyclic loading. The test methods allow for the determination of cyclic tensile modulus at different levels of prescribed or permanent strain, thereby accounting for possible changes in cyclic tensile modulus with increasing permanent strain in the material. These test methods shall be used for research testing and to define properties for use in specific design methods.5.2 In cases of dispute arising from differences in reported test results when using these test methods for acceptance testing of commercial shipments, the purchaser and supplier should conduct comparative tests to determine if there is a statistical bias between their laboratories. Competent statistical assistance is recommended for the investigation of bias. As a minimum, the two parties should take a group of test specimens which are as homogeneous as possible and which are from a lot of material of the type in question. The test specimens should then be randomly assigned in equal numbers to each laboratory for testing. The average results from the two laboratories should be compared using Student’s t-test for unpaired data and an acceptable probability level chosen by the two parties before the testing began. If a bias is found, either its cause shall be found and corrected or the purchaser and supplier shall agree to interpret future test results in light of the known bias.5.3 All geogrids can be tested by Test Method A or B. Some modification of techniques may be necessary for a given geogrid depending upon its physical makeup. Special adaptations may be necessary with strong geogrids, multiple-layered geogrids, or geogrids that tend to slip in the clamps or those which tend to be damaged by the clamps.5.4 Most geotextiles can be tested by Test Method C. Some modification of clamping techniques may be necessary for a given geotextile depending upon its structure. Special clamping adaptations may be necessary with strong geotextiles or geotextiles made from glass fibers to prevent them from slipping in the clamps or being damaged as a result of being gripped in the clamps.5.5 These test methods are applicable for testing geotextiles either dry or wet. It is used with a constant rate of extension type tension apparatus.5.6 These test methods may not be suited for geogrids and geotextiles that exhibit strengths approximately 100 kN/m (600 lbf/in.) due to clamping and equipment limitations. In those cases, 100-mm (4-in.) width specimens may be substituted for 200-mm (8-in.) width specimens.1.1 These test methods cover the determination of small-strain tensile properties of geogrids and geotextiles by subjecting wide-width specimens to cyclic tensile loading.1.2 These test methods (A, B, and C) allow for the determination of small-strain cyclic tensile modulus by the measurement of cyclic tensile load and elongation.1.3 This test method is intended to provide properties for design. The test method was developed for mechanistic-empirical pavement design methods requiring input of the reinforcement tensile modulus. The use of cyclic modulus from this test method for other applications involving cyclic loading should be evaluated on a case-by-case basis.1.4 Three test methods (A, B, and C) are provided to determine small-strain cyclic tensile modulus on geogrids and geotextiles.1.4.1 Test Method A—Testing a relatively wide specimen of geogrid in cyclic tension in kN/m (lbf/ft).1.4.2 Test Method B—Testing multiple layers of a relatively wide specimen of geogrid in cyclic tension in kN/m (lbf/ft).1.4.3 Test Method C—Testing a relatively wide specimen of geotextile in cyclic tension in kN/m (lbf/ft).1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses are provided for information only and are not considered 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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4.1 Due to the variety of small bone fractures, plates used for the fixation of these fractures come in a variety of shapes and configurations. Table 1 categorizes the plate types for each anatomical area. Flat plates are the simplest; see Fig. 2 for an example of a basic flat plate. Many other plates have features to accommodate specific anatomies, such as condylar, complex (such as cuneiform), pre-contoured (such as metatarsophalangeal joint (MPJ)), step, orbital, orthognathic step, and wedge plates. Other plates, such as mesh-based and burr hole plates, are generally flat but are designed to be used in specific anatomical regions, so their designs are not the same as conventional straight plates. If test data is used from one type of plate for justification of the mechanical properties of another type of plate, this justification shall be described in the final report.4.2 Most of the testing described herein is focused on a “functional unit,” which can be described as a single-line fracture being spanned by a plate with one screw hole on each side of the fracture. This configuration allows for the simplest determination of worst-case size if the strut geometry is the determining factor for the worst case. If a worst-case size cannot be isolated to a functional unit/strut geometry, perhaps due to irregular screw hole patterns or the shape of the plate, it is understandable that some tests would need to be modified, or possibly removed from test consideration, to accommodate the shape of the plate or the screw hole. Any test modifications or omissions shall be described in the final report with a rationale related to the plate’s anatomical use, indications, and functional requirements.1.1 This standard is intended to provide guidance for the static testing of small bone metallic plates used for fracture fixation. Small bone plates referred to in this standard would be used in minimally load-bearing anatomical areas of the far extremities, such as the fingers and toes, and in the cranium and upper face. Lower face/mandible, wrist, and ankle fixation plates would generally be larger and carry a substantial amount of load and should not be evaluated under this standard.1.2 ASTM Specification F382 and ISO 9585 are currently available for the testing of metallic bone plates as well, so the user can choose to use any of the tests in these standards for small bone plates. However, due to plate size, Specification F382 and ISO 9585 test setup and execution difficulty can be increased for small bone plates. Thus, this standard offers alternative test methods that are more appropriate for metallic bone plates used in small bone fracture fixation.1.3 This standard is not intended to address the mechanical performance of the plating construct or accessory components (for example, screws and wires).1.4 This standard is intended to provide a basis for the mechanical comparison of small bone plates. Due to the complex and varying biomechanics found in the areas of the body where these plates are used, this standard should only be used to compare the in vitro mechanical performance of small bone plates and not used to infer in vivo performance characteristics.1.5 This standard describes static tests by specifying load types and specific methods of applying these loads. Tests for evaluating and characterizing these loads include the following: static torsion, static cantilever beam bending, static lateral bending, and static three-point bending.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.7 Multiple tests are cited in this standard. However, it must be noted that the user is not obligated to test using all of the described methods. Instead, the user should only select test methods that are appropriate for a particular device design.1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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定价: 590元 / 折扣价: 502 加购物车

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定价: 590元 / 折扣价: 502 加购物车

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定价: 590元 / 折扣价: 502 加购物车

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定价: 590元 / 折扣价: 502 加购物车

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