1.1 本规程涵盖了使用传统超声波脉冲回波探伤设备测量材料中超声波速度的测试程序，其中结果显示在a扫描显示器中。本规程描述了一种方法，通过使用超声波速度准确已知的参考材料进行比较测量来确定材料样品中的未知超声波速度。 1.2 本程序适用于5 mm（0.2 mm）的固体材料 英寸。）厚或更大。垂直于能量传播方向的表面应至少平行于±3°。速度测量的表面光洁度应为3.2μm（125μin）均方根（rms）或更平滑。 注1: 在本实践中，使用米/秒的基本单位引用声波速度，在许多情况下提供英寸/秒作为参考。 对于某些计算，以毫米/微秒为单位考虑速度是很方便的。虽然这些单位在计算中表现良好，但在本实践中，在表格中选择了更自然的单位。通过将小数点向左移动三位，可以简单地将数值从m/s转换为mm/s，即3500 m/s变为3.5 mm/s。 1.3 超声波速度测量有助于确定几个重要的材料特性。如果已知密度，则可以计算具有超声波速度的固体材料的杨氏弹性模量、泊松比、声阻抗和其他几个有用的特性和系数（参见 附录X1 ). 1.4 使用更专业的超声波设备、辅助设备和专业技术，可以获得比使用该方法获得的结果更准确的结果。 中描述了一些补充技术 附录X2 . （材料包含在 附录X2 仅供参考。） 注2: 包括技术、设备、材料类型和操作员变量在内的因素将导致绝对速度读数的变化，有时高达±5 %. 预计上述因素的单一组合的相对结果会更加准确（可能在1%以内） % 公差）。 1.5 单位- 以国际单位制表示的数值应视为标准值。国际单位制后括号中给出的值仅供参考，不被视为标准值。 1.6 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。 1.7 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 本实施规程描述了一种试验程序，用于应用常规超声波方法，通过使用超声波速度准确已知的参考材料进行比较测量来确定材料样品中的未知超声波速度。 5.2 虽然本实施规程中描述的所有方法并非同等或普遍适用于不同材料中的所有速度测量，但它确实为用户之间建立合同标准提供了灵活性和基础，并且可以用作为特定应用准备详细程序或规范的一般指南。 5.3 本规程旨在使用适当的声波形式确定纵波和横波速度。本规程还概述了测定弹性模量的方法，可用于接触和浸入模式。

1.1 This practice covers a test procedure for measuring ultrasonic velocities in materials with conventional ultrasonic pulse echo flaw detection equipment in which results are displayed in an A-scan display. This practice describes a method whereby unknown ultrasonic velocities in a material sample are determined by comparative measurements using a reference material whose ultrasonic velocities are accurately known. 1.2 This procedure is intended for solid materials 5 mm (0.2 in.) thick or greater. The surfaces normal to the direction of energy propagation shall be parallel to at least ±3°. Surface finish for velocity measurements shall be 3.2 μm (125 μin.) root-mean-square (rms) or smoother. Note 1: Sound wave velocities are cited in this practice using the fundamental units of meters per second, with inches per second supplied for reference in many cases. For some calculations, it is convenient to think of velocities in units of millimeters per microsecond. While these units work nicely in the calculations, the more natural units were chosen for use in the tables in this practice. The values can be simply converted from m/s to mm/μs by moving the decimal point three places to the left, that is, 3500 m/s becomes 3.5 mm/μs. 1.3 Ultrasonic velocity measurements are useful for determining several important material properties. Young's modulus of elasticity, Poisson's ratio, acoustic impedance, and several other useful properties and coefficients can be calculated for solid materials with the ultrasonic velocities if the density is known (see Appendix X1 ). 1.4 More accurate results than those obtained using this method can be obtained with more specialized ultrasonic equipment, auxiliary equipment, and specialized techniques. Some of the supplemental techniques are described in Appendix X2 . (Material contained in Appendix X2 is for informational purposes only.) Note 2: Factors including techniques, equipment, types of material, and operator variables will result in variations in absolute velocity readings, sometimes by as much as ±5 %. Relative results with a single combination of the above factors can be expected to be much more accurate (probably within a 1 % tolerance). 1.5 Units— The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units 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. ====== Significance And Use ====== 5.1 This practice describes a test procedure for the application of conventional ultrasonic methods to determine unknown ultrasonic velocities in a material sample by comparative measurements using a reference material whose ultrasonic velocities are accurately known. 5.2 Although not all methods described in this practice are applied equally or universally to all velocity measurements in different materials, it does provide flexibility and a basis for establishing contractual criteria between users, and may be used as a general guideline for preparing a detailed procedure or specification for a particular application. 5.3 This practice is directed towards the determination of longitudinal and shear wave velocities using the appropriate sound wave form. This practice also outlines methods to determine elastic modulus and can be applied in both contact and immersion mode.