In September 2017, the international standard ISO 20407:2017 "Fine ceramics (advanced ceramics, advanced technical ceramics) — Test method for interfacial tensile and shear fatigue properties of ceramic joining loaded in constant amplitude at room temperature," mainly drafted and promoted by CTC, was officially published at ISO headquarters. This is the seventh ISO international standard successfully published by CTC, following ISO 13124, the first international standard in China's building materials industry transformed from independent intellectual property technology, and was independently completed by the Central Research Institute led by Chief Scientist Bao Yiwang. We persist in exploring the development path of "technology patenting, patent standardization, and standard internationalization." To date, CTC has cumulatively successfully published 9 international standards, including 7 ISO international standards and 2 IEC international standards.

With the rapid development of materials science and engineering mechanics, welding and bonding between high-performance ceramics and other solid materials have become increasingly important. Many ceramic materials are used as ceramic/ceramic and ceramic/metal bonded components, such as thermal protection layers for spacecraft, coatings with good wear resistance, and laminated components of ceramic-to-metal welding. The quality and reliability of welded interfaces are closely related to the intrinsic strength, interfacial bonding strength, and interfacial fatigue properties of structural solid materials. Accurately evaluating the interfacial fatigue properties of ceramic materials is crucial for the safety and reliability design of ceramic material structural components and material optimization. This international standard proposes a simple method for testing the interfacial tensile strength and shear strength of brittle materials under high-temperature environments, effectively solving the difficulty of testing the bonding interface strength of materials such as ceramics and glass, and breaking through the technical bottleneck that there was no evaluation method for high-temperature interfacial fatigue strength during the application of ceramic materials as high-temperature structural materials.

The international standard was officially approved as a project in ISO/TC 206 in January 2016. After more than one year, it went through multiple stages including NP, WD, CD, DIS, and FDIS. After multiple international meeting discussions, a large number of opinions from international industry experts and competitors were received. Through detailed summarization, analysis, and calculation of various opinions, and a large amount of experimental verification of the influence of various test factors, it finally obtained unanimous recognition from international experts.

ISO 20407, based on the cross-cross method, establishes a test method for testing the interfacial tensile and shear fatigue properties of ceramic materials under constant amplitude conditions. Its successful publication can not only accurately evaluate the interfacial tensile and shear fatigue properties of ceramic materials under constant amplitude conditions, but also more accurately obtain the physical properties of the ceramic material bonding interface. It is conducive to giving play to the actual role of ceramic materials, guiding timely replacement after failure, and reducing the incidence of safety accidents. It is of great significance for ensuring the safety and reliability of the entire structure, optimizing production processes, and especially for military products and national defense construction. At the same time, it also demonstrates CTC's innovation capability and core competitiveness as a high-tech service industry in inspection and certification. In the future, CTC will continue to focus on scientific research and innovation capabilities, and strive for more international discourse power for the development of China's building materials testing industry!