Russian scientists have developed an innovative approach to studying the structure of composite materials that changes under external influence in real time. This methodology provides important data from miniature samples, which can now be tested in a scanning electron microscope chamber. The results obtained are used for reliable strength calculations, which will save costs in the production and testing of automotive and aerospace components.
In modern aviation and space exploration, materials with high specific strength, lightweight, durability, and resilience to failure are especially valued. One such material is carbon fiber reinforced plastic, but designing products from it is challenging due to its heterogeneous composite nature: the combination of carbon fibers and a polymer matrix. Specifically, failure processes are much more complex than in metal alloys. Engineers require new computational-experimental approaches.
Traditional testing methods for carbon fiber composites use large samples. Moreover, failure analysis is conducted on composites that have already been deformed after testing, thus missing details about the interaction between fibers and the matrix and the distribution of internal stresses.
Using an electron microscope, scientists from NUST MISIS, Skoltech, and MAI tracked changes occurring in miniature samples of carbon fiber reinforced polymer directly under mechanical load by stretching material plates that are 0.5 mm thick.
“To ensure the stability of the properties of carbon composites, it was proposed to begin their study at the micro level and then transfer the data to larger objects through computer modeling and experimentation. This will eliminate the need to use large samples each time. We were able to study micro-deformation processes affecting the mechanical behavior of the composite in real time. In situ method recorded the dynamics of deformation, crack formation, and the interaction between fibers and the matrix during stretching,” said Evgeny Statnik, an associate professor at the Department of Physical Chemistry and a member of the Laboratory of Accelerated Particles “LUCh” at NUST MISIS.
All changes and disruptions in the structure of polymer composites at the level of individual fibers and epoxy matrix are captured by researchers using digital cameras. By employing algorithms that analyze video data, scientists observed nuances of deformations and identified types of defects that could degrade the properties of the studied material.
“The results of our research will help predict the emergence and development of damage in composites, which, in turn, will reduce costs and improve the development of components for aircraft, transportation, space technology, construction materials, and sports equipment made from carbon fiber composites,” added Evgeny Statnik.
Details of the research have been published in the scientific journal Fracture and Structural Integrity (Q2). The work was carried out with support from the Ministry of Science and Higher Education of Russia (project No.
