1.1 这些测试方法包括断裂韧性， K 集成电路 ，在环境温度下测定高级陶瓷。方法决定 K Ipb （预裂梁试样）， K Isc公司 （弯曲中的表面裂纹），以及 K Ivb公司 （V形切口梁试样）。使用带有尖锐裂纹的梁试样确定断裂韧性值。裂纹要么是通过桥弯曲（pb）形成的直通裂纹，要么是通过努氏压痕（sc）形成的半椭圆表面裂纹，要么是在人字形缺口（vb）中形成和扩展的，如所示 图1 . 1.6 这些试验方法中表示的数值符合国际单位制（SI）和 IEEE/ASTM SI 10 . 1.7 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.8 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。 1.9 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 断裂韧性， K 集成电路 ，是衡量脆性材料中裂纹扩展阻力的指标。这些试验方法可用于材料开发、材料比较、质量评估和表征。 5.2 pb和vb断裂韧性值提供了包含大尖锐裂纹的高级陶瓷的断裂阻力信息，而sc断裂韧性值提供了与自然断裂源大小相当的小裂纹的信息。sc法可使用不同尺寸的裂纹。如果断裂韧性值随裂纹尺寸的变化而变化，则可以预计 K Isc公司 将不同于 K Ipb 和 K Ivb公司 . 表1 列出每种方法的优点、缺点和适用性。

1.1 These test methods cover the fracture toughness, K Ic , determination of advanced ceramics at ambient temperature. The methods determine K Ipb (precracked beam test specimen), K Isc (surface crack in flexure), and K Ivb (chevron-notched beam test specimen). The fracture toughness values are determined using beam test specimens with a sharp crack. The crack is either a straight-through crack formed via bridge flexure (pb), or a semi-elliptical surface crack formed via Knoop indentation (sc), or it is formed and propagated in a chevron notch (vb), as shown in Fig. 1 . 1.6 Values expressed in these test methods are in accordance with the International System of Units (SI) and IEEE/ASTM SI 10 . 1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 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. ====== Significance And Use ====== 5.1 Fracture toughness, K Ic , is a measure of the resistance to crack extension in a brittle material. These test methods may be used for material development, material comparison, quality assessment, and characterization. 5.2 The pb and the vb fracture toughness values provide information on the fracture resistance of advanced ceramics containing large sharp cracks, while the sc fracture toughness value provides this information for small cracks comparable in size to natural fracture sources. Cracks of different sizes may be used for the sc method. If the fracture toughness values vary as a function of the crack size it can be expected that K Isc will differ from K Ipb and K Ivb . Table 1 tabulates advantages, disadvantages, and applicability of each method.