5.1 Plastics are viscoelastic and therefore are likely to be sensitive to changes in velocity of the mass falling on their surfaces. However, the velocity of a free-falling object is a function of the square root of the drop height. A change of a factor of two in the drop height will cause a change of only 1.4 in velocity. Hagan et al (2) found that the mean-failure energy of sheeting was constant at drop heights between 0.30 and 1.4 m. This suggests that a constant mass-variable height method will give the same results as the constant height-variable mass technique. On the other hand, different materials respond differently to changes in the velocity of impact. While both constant-mass and constant-height techniques are permitted by these methods, the constant-height method is to be used for those materials that are found to be rate-sensitive in the range of velocities encountered in falling-weight types of impact tests.5.2 The test geometry FA causes a moderate level of stress concentration and can be used for most plastics.5.3 Geometry FB causes a greater stress concentration and results in failure of tough or thick specimens that do not fail with Geometry FA (3). This approach can produce a punch shear failure on thick sheet. If that type of failure is undesirable, Geometry FC is to be used. Geometry FB is suitable for research and development because of the smaller test area required.5.3.1 The conical configuration of the 12.7-mm diameter tup used in Geometry FB minimizes problems with tup penetration and sticking in failed specimens of some ductile materials.5.4 The test conditions of Geometry FC are the same as those of Test Method A of Test Method D1709. They have been used in specifications for extruded sheeting. A limitation of this geometry is that considerable material is required.5.5 The test conditions of Geometry FD are the same as for Test Method D3763.5.6 The test conditions of Geometry FE are the same as for ISO 6603-1.5.7 Because of the nature of impact testing, the selection of a test method and tup must be somewhat arbitrary. Although a choice of tup geometries is available, knowledge of the final or intended end-use application shall be considered.5.8 Clamping of the test specimen will improve the precision of the data. Therefore, clamping is recommended. However, with rigid specimens, valid determinations can be made without clamping. Unclamped specimens tend to exhibit greater impact resistance.5.9 Before proceeding with this test method, reference the specification of the material being tested. Table 1 of Classification System D4000 lists the ASTM materials standards that currently exist. Any test specimens preparation, conditioning, dimensions, or testing parameters or combination thereof covered in the relevant ASTM materials specification shall take precedence over those mentioned in this test method. If there are no relevant ASTM material specifications, then the default conditions apply.1.1 This test method covers the determination of the threshold value of impact-failure energy required to crack or break flat, rigid plastic specimens under various specified conditions of impact of a free-falling dart (tup), based on testing many specimens.1.2 The values stated in SI units are to be regarded as the standard. The values 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. Specific hazard statements are given in Section 8.NOTE 1: This test method and ISO 6603-1 are technically equivalent only when the test conditions and specimen geometry required for Geometry FE and the Bruceton Staircase method of calculation are used.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 relative simplicity of the test method makes it applicable for a wide range of materials (4, 5). The technique is capable of fast measurements, making it possible to take data before the materials suffer thermal degradation. Alternatively, it is possible to study the effect of compositional changes such as chemical reaction or aging (6). Short measurement times permit generation of large amounts of data with little effort. The line-source probe and the accompanying test specimen are small in size, making it possible to subject the sample to a wide range of test conditions. Because this test method does not contain a numerical precision and bias statement, it shall not be used as a referee test method in case of dispute.1.1 This test method covers the determination of the thermal conductivity of plastics over a temperature range from –40 to 400°C. It is possible to measure the thermal conductivity of filled and unfilled thermoplastics, thermosets, and rubbers in the range from 0.08 to 2.0 W/m.K.1.2 The values stated in SI units shall be regarded as standard.1.3 This standard does not purport to address the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish proper safety and health practices and determine the applicability of regulatory limitations prior to use.NOTE 1: There is no known ISO equivalent to this test method.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 This test method provides a rapid means of determining the steady-state thermal transmission properties of thermal insulations and other materials with a high level of accuracy when the apparatus has been calibrated appropriately.4.2 Proper calibration of the heat flow meter apparatus requires that it be calibrated using specimen(s) having thermal transmission properties determined previously by Test Methods C177, or C1114.NOTE 1: Calibration of the apparatus typically requires specimens that are similar to the types of materials, thermal conductances, thicknesses, mean temperatures, and temperature gradients as expected for the test specimens.4.3 The thermal transmission properties of specimens of a given material or product may vary due to variability of the composition of the material; be affected by moisture or other conditions; change with time; change with mean temperature and temperature difference; and depend upon the prior thermal history. It must be recognized, therefore, that the selection of typical values of thermal transmission properties representative of a material in a particular application should be based on a consideration of these factors and will not apply necessarily without modification to all service conditions.4.3.1 As an example, this test method provides that the thermal properties shall be obtained on specimens that do not contain any free moisture although in service such conditions may not be realized. Even more basic is the dependence of the thermal properties on variables, such as mean temperature and temperature difference. These dependencies should be measured or the test made at conditions typical of use.4.4 Special care shall be taken in the measurement procedure for specimens exhibiting appreciable inhomogeneities, anisotropies, rigidity, or especially high or low resistance to heat flow (see Practice C1045). The use of a heat flow meter apparatus when there are thermal bridges present in the specimen may yield very unreliable results. If the thermal bridge is present and parallel to the heat flow the results obtained may well have no meaning. Special considerations also are necessary when the measurements are conducted at either high or low temperatures, in ambient pressures above or below atmospheric pressure, or in special ambient gases that are inert or hazardous.4.5 The determination of the accuracy of the method for any given test is a function of the apparatus design, of the related instrumentation, and of the type of specimens under test (see Section 10), but this test method is capable of determining thermal transmission properties within ± 2 % of those determined by Test Method C177 when the ambient temperature is near the mean temperature of the test (T (ambient) = T (mean) ± 1°C), and in the range of 10 to 40°C. In all cases the accuracy of the heat flow meter apparatus can never be better than the accuracy of the primary standards used to calibrate the apparatus.4.5.1 When this test method is to be used for certification testing of products, the apparatus shall have the capabilities required in A1.7 and one of the following procedures shall be followed:4.5.1.1 The apparatus shall have its calibration checked within 24 h before or after a certification test using either secondary transfer standards traceable to, or calibration standards whose values have been established by, a recognized national standards laboratory not more than five years prior to the certification date. The average of two calibrations shall be used as the calibration factor and the specimen(s) certified with this average value. When the change in calibration factor is greater than 1 %, the standard specimen shall be retested and a new average calculated. If the change in calibration factor is still greater than 1 % the apparatus shall be calibrated using the procedure in Section 6.4.5.1.2 Where both the short and long term stability of the apparatus have been proven to be better than 1 % of the reading (see Section 10), the apparatus may be calibrated at less frequent intervals, not exceeding 30 days. The specimens so tested cannot be certified until after the calibration test following the test and then only if the change in calibration factor from the previous calibration test is less than 1 %. When the change in calibration is greater than 1 %, test results from this interval shall be considered void and the tests repeated in accordance with 4.5.1.1.4.5.2 The precision (repeatability) of measurements made by the heat flow meter apparatus calibrated as in Section 6.6 normally are much better than ±1 % of the mean value. This precision is required to identify changes in calibration and is desirable in quality control applications.1.1 This test method covers the measurement of steady state thermal transmission through flat slab specimens using a heat flow meter apparatus.1.2 The heat flow meter apparatus is used widely because it is relatively simple in concept, rapid, and applicable to a wide range of test specimens. The precision and bias of the heat flow meter apparatus can be excellent provided calibration is carried out within the range of heat flows expected. This means calibration shall be carried out with similar types of materials, of similar thermal conductances, at similar thicknesses, mean temperatures, and temperature gradients, as expected for the test specimens.1.3 This a comparative, or secondary, method of measurement since specimens of known thermal transmission properties shall be used to calibrate the apparatus. Properties of the calibration specimens must be traceable to an absolute measurement method. The calibration specimens should be obtained from a recognized national standards laboratory.1.4 The heat flow meter apparatus establishes steady state one-dimensional heat flux through a test specimen between two parallel plates at constant but different temperatures. By appropriate calibration of the heat flux transducer(s) with calibration standards and by measurement of the plate temperatures and plate separation. Fourier’s law of heat conduction is used to calculate thermal conductivity, and thermal resistivity or thermal resistance and thermal conductance.1.5 This test method shall be used in conjunction with Practice C1045. Many advances have been made in thermal technology, both in measurement techniques and in improved understanding of the principles of heat flow through materials. These advances have prompted revisions in the conceptual approaches to the measurement of the thermal transmission properties (1-4).2 All users of this test method should be aware of these concepts.1.6 This test method is applicable to the measurement of thermal transmission through a wide range of specimen properties and environmental conditions. The method has been used at ambient conditions of 10 to 40°C with thicknesses up to approximately 250 mm, and with plate temperatures from –195°C to 540°C at 25-mm thickness (5, 6).1.7 This test method may be used to characterize material properties, which may or may not be representative of actual conditions of use. Other test methods, such as Test Methods C236 or C976 should be used if needed.1.8 To meet the requirements of this test method the thermal resistance of the test specimen shall be greater than 0.10 m2·K/W in the direction of the heat flow and edge heat losses shall be controlled, using edge insulation, or a guard heater, or both.1.9 It is not practical in a test method of this type to try to establish details of construction and procedures to cover all contingencies that might offer difficulties to a person without pertinent technical knowledge. Thus users of this test method shall have sufficient knowledge to satisfactorily fulfill their needs. For example, knowledge of heat transfer principles, low level electrical measurements, and general test procedures is required.1.10 The user of this method must be familiar with and understand the Annex. The Annex is critically important in addressing equipment design and error analysis.1.11 Standardization of this test method is not intended to restrict in any way the future development of improved or new methods or procedures by research workers.1.12 Since the design of a heat flow meter apparatus is not a simple matter, a procedure for proving the performance of an apparatus is given in Appendix X3.1.13 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.14 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.1.15 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 Plastics are viscoelastic and it is possible that they are sensitive to changes in velocity of weights falling on their surfaces. However, the velocity of a free-falling object is a function of the square root of the drop height. A change of a factor of two in the drop height will cause a change of only 1.4 in velocity. Hagan, et al (2) found that the mean-failure energy of sheeting was constant at drop heights between 0.30 and 1.4 m. Different materials respond differently to changes in the velocity of impact.5.2 The test conditions used in Geometry GA are the same as those used in Geometry FA of Test Method D5628 (see Table 1).5.3 The test conditions of Geometry GB are equivalent to the geometry used for the Gardner Variable Height Impact Test (3).5.4 The test conditions of Geometry GC cause a punch-shear type of failure because the support-plate hole is close to the diameter of the striker.5.5 The test conditions of Geometry GD are the same as those in Test Method D3763.5.6 The test conditions of Geometry GE are the same as those in Test Method D4226, impactor head configuration H.25.5.7 Because of the nature of impact testing, the selection of a test method and striker must be somewhat arbitrary. Consider the end use environment and requirements when choosing from the available striker geometries. The selection of any one of the striker geometries is permitted.NOTE 2: Material processing can have a significant affect on the development of a plastic's physical properties. Consult relevant material standards for processing guidelines1.1 This test method covers the determination of the relative ranking of materials according to the energy required to crack or break flat, rigid plastic specimens under various specified conditions of impact of a striker impacted by a falling weight.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.NOTE 1: There is no known ISO equivalent to this standard.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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3.1 This test method is designed to measure the apparent torsional modulus3 of a leather specimen. Experience has shown that the torsion modulus of leather is directly related to the characteristic known as stiffness when felt in a glove.41.1 This test method describes the use of a torsional apparatus for measuring the relative stiffness of gloving leathers. This test method does not apply to wet blue.1.2 The values stated in SI units are to be regarded as the standard. The values shown in parentheses are provided 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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