1.1 目的- 本规程涵盖了使用振动声学热成像技术对部件进行检查所需的程序。 1.2 应用程序- 振动声学热成像工艺已用于飞机、发电、汽车和其他行业的部件检查，用于测试新的和维修的部件，包括涂层和未涂层的部件。目前的应用主要针对金属部件，但复合材料和陶瓷部件的应用正在开发中( 1. ). 2. 1.3 背景- 振动声学热成像是主动热成像领域的一项新技术。该技术于1979年由Henneke等人首次发表( 2. )Favro等人对其进行了扩展和推广( 3. ). 在测试过程中，红外摄像机检测到由通常在15 kHz至40 kHz范围内的超声波能量短脉冲引起的缺陷热响应。 耦合到被测部件中的超声波可以激活具有接触区域的缺陷中的热响应，这些接触区域可以相互移动，即裂纹和分层。根据需要和能力，通常使用不同的通电和耦合技术。这些变化和向下选择过程不包括在程序中，应通过实验为每个新组件应用开发/优化。 注1: 振动声学热成像通常对紧密的平面缺陷敏感( 4. ). 体积缺陷，如孔隙、夹杂物、开口破裂或大开口区域中的裂纹，通常不会导致显示。因此，应采用增强方法来检测体积缺陷。（参见术语 E1316 .) 注2: 振动声学热成像是一种表面检查，但已证明对次表面缺陷（包括薄部件的后壁缺陷）具有检测灵敏度( 5. ), ( 6. ). 在开发振动声学热成像以检测地下缺陷时，应小心。 1.4 警告: 1.4.1 警告- 振动声学热成像法要求用振动能量给试样通电。通电期间，整个部件可能会被振动声（振动）能量激发长达数秒。为新应用开发此测试需要特殊测量、预防措施和注意组件响应。熟悉该技术的部件设计工程师和无损检测工程专家应确信试验不会造成损坏或缩短使用寿命。 1.4.2 警告- 与任何其他无损检测技术一样，振动声学热成像技术需要对每种应用进行彻底的开发和测试，包括明确定义检查目标，以及开发客观手段，以区分可拒绝的指示和不应导致拒绝的条件。 不完整的开发和应用将导致不当拒绝的高发生率和缺陷“遗漏”的高发生率许多振动声学热成像检查产生的图像可能会导致检查员疲劳和无效评估。 1.5 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。 1.6 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。

1.1 Purpose— This practice covers procedures required to conduct an examination of components using vibroacoustic thermography. 1.2 Application— The vibroacoustic thermography process has been used for component inspections in the aircraft, power generation, automotive, and other industries for testing new and serviced components, both coated and uncoated. Current applications are mostly targeting metallic components, but composite and ceramic component applications are under development ( 1 ). 2 1.3 Background— Vibroacoustic thermography is a new technique within the area of active thermography. The technique was first published by Henneke, et al. in 1979 ( 2 ) and has been expanded on and popularized by Favro, et al. ( 3 ). During the test, a defect thermal response resulting from a short burst of ultrasonic energy typically in the range of 15 kHz to 40 kHz is detected by an infrared camera. The ultrasound coupled into the component being tested can activate a thermal response in defects with contact areas that can move against each other, that is, cracks and delamination. There are different energizing and coupling techniques that are commonly used depending on the needs and capabilities. These variations and the down selection process are not included in the procedure and should be developed/optimized by experimentation for each new component application. Note 1: Vibroacoustic thermography is typically sensitive to tight planar defects ( 4 ). Volumetric defects such as porosity, inclusions, open ruptures, or cracks in wide-open areas, will not typically result in an indication. Therefore, an augmenting method should be conducted to detect volumetric defects. (See Terminology E1316 .) Note 2: Vibroacoustic thermography is a surface examination but has demonstrated detection sensitivity for subsurface defects including back wall defects for thin components ( 5 ), ( 6 ). Care should be taken when developing vibroacoustic thermography for the detection of subsurface defects. 1.4 Warnings: 1.4.1 Warning— Vibroacoustic thermography requires the energization of the test article with vibrational energy. During energization, the complete component may be excited with vibroacoustic (vibration) energy for as long as several seconds. The development of this test for a new application requires special measurements, precautions, and attention to component response. The component design engineer and the NDE engineering specialist knowledgeable of this technique should be satisfied that the test will not cause damage or reduction of service life. 1.4.2 Warning— Vibroacoustic thermography, like any other NDT technology, requires thorough development and testing for each application, including clear definition of the inspection objective, as well as development of objective means to distinguish between rejectable indications and conditions that should not be cause for rejection. Incomplete development and application will result in high incidence of improper rejections and high incidence of defect "misses." The images produced by many vibroacoustic thermography inspections can otherwise lead to inspector fatigue and ineffective evaluations. 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.