Without the use of carbon fiber reinforced plastics, it is difficult to imagine the development of today's aviation, aerospace, and automotive industries. These composite materials are widely used due to their unique properties. In fact, this material is not as good as other composite materials in terms of crack resistance. A scientist at the Southern Ural National University and a Belgian colleague demonstrated a crack-resistant material. This research represents the latest step in solving the problem of crack-resistant pseudoplastic composites. Articles about this research were published in one of the most famous journals "Composite Structures" (Scopus Q1)
Cracks in durable composites
Carbon fiber composite materials have been used for decades. Their use in the aerospace field is very popular. In these areas, materials that are lightweight but still have sufficient strength are valued. Carbon fiber materials meet this requirement: they have high temperature resistance, corrosion resistance, robustness, and good rigidity. However, they have lower crack resistance than other materials, such as fiberglass. If you try to apply a force beyond the bearing capacity of the structure made of this material, the structure will collapse almost immediately. Therefore, for scientists studying composite materials, it is important to check the overload capacity of each material and determine its crack resistance.
Professor Sergey Sapozhnikov of Southern Ural National University (SUSU) conducted corresponding research on new carbon composite materials. This unique hybrid material is designed on the basis of ultra-high modulus and high-strength carbon fiber. So far, there is no unified opinion between them, and there is no subject in the scientific literature concerning the critical energy of the development of this hybrid crack.
This work was carried out with colleagues from the Catholic University of Leuven, Belgium. Based on his theoretical development, Sergey Sapozhnikov made a new type of carbon composite material with the highest quality Japanese parts. In the first stage, scientists simulated a situation where every sample of the composite material had artificial cracks. For this purpose, when creating a composite material, a thin aluminum foil is placed inside. Then continue this "crack" to the desired length and wedge the sample. Through testing, the transverse shear crack resistance of the material was determined. Scanning electron microscopy and microcomputer X-ray tomography were used to demonstrate the strong crack resistance detected due to the adhesion of contact surfaces made of various composite materials.
"The development of cracks is undesirable in practice, because if the crack reaches a critical length, the complete structure will be destroyed. In this case, when the crack appears and develops, the external deformation may not be visible. We proceed The test is necessary for future use on carbon fiber structural elements that may crack. Our research provides a basis for preparing pseudoplastic composite materials with high shear crack resistance from the materials studied. These materials are expensive , Light, durable, and almost insensitive to stress concentrators. "Sergey Sapozhnikov said.
Future Research Foundation
Transverse shear fracture toughness is not directly included in the design calculations. Therefore, the professor explained that the study has no direct practical application. However, the team of scientists refers to this work as basic work, which provides an excellent opportunity to produce modern materials with unique characteristics from known and relatively easily available components that do not have such characteristics. Articles written by the scientists of the above group on the characteristics of the new pseudoplastic carbon fiber are currently being printed. Similarly, experts who have previously checked the performance of mixed composites under single load intend to study the performance of this material under cyclic loading. In other words, this topic will be developed in the study of fatigue strength of polymer composites.
In addition, Professor Sapozhnikov and colleagues from Leuven are planning to participate in the European Composites Conference and Exhibition. The team will submit three reports on modern materials (pseudoplastic carbon fiber and its characteristics).
Multidisciplinary research in the field of materials science is one of the three strategic directions of scientific and academic activities, digital industry and ecological development of Southern Ural National University.
The Southern Ural State University (SUSU) is a participant in the "5-100" project, which aims to increase the competitiveness of Russian universities in the world's leading research and academic centers.