1.1 本试验方法包括在环境温度下测定高级陶瓷的动态弹性性能。这些材料的试样具有特定的机械共振频率，该频率由试样的弹性模量、质量和几何形状决定。因此，如果可以测量材料的适当（矩形、圆柱形或圆盘几何形状）试样的几何形状、质量和机械共振频率，则可以计算材料的动态弹性特性。弯曲和扭转中的共振频率是通过使用冲击工具（第2.1.1节）在奇异弹性冲击的支撑模式下激发试样的振动来测量的 4. 和 图1 ，图3和图4）。动态杨氏模量是使用弯曲振动模式中的共振频率确定的。动态剪切模量或刚度模量是通过扭转共振找到的。动态杨氏模量和动态剪切模量用于计算泊松比。 图1 典型试验装置框图 1.2 尽管本文没有具体描述，但根据试验方法第9.2、9.3和10.4小节的规定，也可以在低温和高温下进行本试验方法，并对设备进行适当的修改和计算进行适当的修改，以补偿热膨胀 C1198 . 1.3 有材料- 具体ASTM标准，包括通过声波共振或振动冲击激励确定特定材料的共振频率和弹性特性。试验方法 C215型 , C623 , C747 , C848 , C1198 , E1875 和 E1876 可能在几个方面与本试验方法不同（例如，样品尺寸、尺寸公差、样品制备、计算细节等）。这些材料的测试应符合适当的材料特定标准。在可能的情况下，本标准中的程序、样品规格和计算与其他试验方法一致。 1.4 本试验方法使用棒材、棒材和圆盘几何形状的试样。 主体部分描述了杆和杆的几何形状。圆盘几何形状见 附件A1 . 1.5 该测试方法的修改可用于质量控制和无损评估，使用共振频率的变化来检测试样几何形状、质量和内部缺陷的变化。（参见 5.5 .) 1.6 以国际单位制表示的数值应视为标准值。括号中给出的非国际单位制数值仅供参考，不被视为标准值。 1.7 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.8 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 该试验方法可用于材料开发、表征、设计数据生成和质量控制目的。 5.2 本试验方法特别适用于测定弹性、均匀和各向同性高级陶瓷的模量 ( 1. ) . 4. 5.3 本试验方法涉及在室温下测定细长杆（矩形横截面）和杆（圆柱形）的动态弹性模量。 也可以类似地测量平板和圆盘，但本文不讨论确定模量所需的方程。 5.4 这种动态测试方法与静态加载技术和需要连续激励的共振技术有几个优点和区别。 5.4.1 该试验方法本质上是无损的，可用于为其他试验准备的试样。试样承受微小应变；因此，在应力-应变曲线原点处或附近测量模量，断裂可能性最小。 5.4.2 冲击激励试验使用冲击工具和试样的简单支架。不需要复杂的支持系统，需要精心设置或对齐。 5.5 该技术可单独用于测量谐振频率，用于质量控制和验收规则形状和复杂形状的试样。确定具有特定几何形状和质量的试样的可接受共振频率范围。试样尺寸或质量和内部缺陷（裂纹、分层、不均匀性、孔隙度等）的偏差将改变该试样的共振频率。任何共振频率低于规定频率范围的样品均被拒收。只要已知所选频率范围的极限包括试样必须具有的共振频率（如果其几何形状、质量和内部结构在规定公差范围内），则无需确定每个试样的实际模量。 该技术特别适用于具有复杂几何形状（平行六面体、圆柱体/杆或圆盘除外）的试样，这些几何形状不适合通过其他程序进行测试。这类似于指南中描述的评估方法 E2001年 . 5.6 如果热处理或环境暴露影响试样的弹性响应，则本试验方法可适用于确定热历史、环境暴露等的特定影响。试样描述应包括试样已接受的任何特定热处理或环境暴露。

1.1 This test method covers determination of the dynamic elastic properties of advanced ceramics at ambient temperatures. Specimens of these materials possess specific mechanical resonant frequencies that are determined by the elastic modulus, mass, and geometry of the test specimen. The dynamic elastic properties of a material can therefore be computed if the geometry, mass, and mechanical resonant frequencies of a suitable (rectangular, cylindrical, or disc geometry) test specimen of that material can be measured. The resonant frequencies in flexure and torsion are measured by excitation of vibrations of the test specimen in a supported mode by a singular elastic strike with an impulse tool (Section 4 and Fig. 1 , Fig. 3, and Fig. 4). Dynamic Young’s modulus is determined using the resonant frequency in the flexural mode of vibration. The dynamic shear modulus, or modulus of rigidity, is found using torsional resonant vibrations. Dynamic Young’s modulus and dynamic shear modulus are used to compute Poisson’s ratio. FIG. 1 Block Diagram of Typical Test Apparatus 1.2 Although not specifically described herein, this test method can also be performed at cryogenic and high temperatures with suitable equipment modifications and appropriate modifications to the calculations to compensate for thermal expansion, in accordance with Subsections 9.2, 9.3, and 10.4 of Test Method C1198 . 1.3 There are material-specific ASTM standards that cover the determination of resonance frequencies and elastic properties of specific materials by sonic resonance or by impulse excitation of vibration. Test Methods C215 , C623 , C747 , C848 , C1198 , E1875 , and E1876 may differ from this test method in several areas (for example, sample size, dimensional tolerances, sample preparation, calculation details, etc.). The testing of those materials should be done in compliance with the appropriate material-specific standards. Where possible, the procedures, sample specifications, and calculations in this standard are consistent with the other test methods. 1.4 This test method uses test specimens in bar, rod, and disc geometries. The rod and bar geometries are described in the main body. The disc geometry is addressed in Annex A1 . 1.5 A modification of this test method can be used for quality control and nondestructive evaluation, using changes in resonant frequency to detect variations in specimen geometry and mass and internal flaws in the specimen. (See 5.5 .) 1.6 The values stated in SI units are to be regarded as standard. The non-SI unit values given in parentheses are for information only and are not considered standard. 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. ====== Significance And Use ====== 5.1 This test method may be used for material development, characterization, design data generation, and quality control purposes. 5.2 This test method is specifically appropriate for determining the modulus of advanced ceramics that are elastic, homogeneous, and isotropic ( 1 ) . 4 5.3 This test method addresses the room temperature determination of dynamic moduli of elasticity of slender bars (rectangular cross section) and rods (cylindrical). Flat plates and discs may also be measured similarly, but the required equations for determining the moduli are not addressed herein. 5.4 This dynamic test method has several advantages and differences from static loading techniques and from resonant techniques requiring continuous excitation. 5.4.1 The test method is nondestructive in nature and can be used for specimens prepared for other tests. The specimens are subjected to minute strains; hence, the moduli are measured at or near the origin of the stress-strain curve, with the minimum possibility of fracture. 5.4.2 The impulse excitation test uses an impact tool and simple supports for the test specimen. There is no requirement for complex support systems that require elaborate setup or alignment. 5.5 This technique can be used to measure resonant frequencies alone for the purposes of quality control and acceptance of test specimens of both regular and complex shapes. A range of acceptable resonant frequencies is determined for a specimen with a particular geometry and mass. Deviations in specimen dimensions or mass and internal flaws (cracks, delaminations, inhomogeneities, porosity, etc.) will change the resonant frequency for that specimen. Any specimen with a resonant frequency falling outside the prescribed frequency range is rejected. The actual modulus of each specimen need not be determined as long as the limits of the selected frequency range are known to include the resonant frequency that the specimen must possess if its geometry and mass and internal structure are within specified tolerances. The technique is particularly suitable for testing specimens with complex geometries (other than parallelepipeds, cylinders/rods, or discs) that would not be suitable for testing by other procedures. This is similar to the evaluation method described in Guide E2001 . 5.6 If a thermal treatment or an environmental exposure affects the elastic response of the test specimen, this test method may be suitable for the determination of specific effects of thermal history, environment exposure, etc. Specimen descriptions should include any specific thermal treatments or environmental exposures that the specimens have received.