Micromechanical analysis of fatigue and crack growth in carbon-fiber epoxy composites based on mechanical testing

Abstract

The paper presents static and dynamic tests of carbon/epoxy composite materials with fiber orientation at 0?/90? and ?45?. The main tensile properties were determined as a basis for subsequent dynamic tests, in which permanent dynamic strength, crack growth, and crack growth rate in the material due to the action of fatigue load were assessed. Comparisons were made regarding the structure of the tested specimens. Samples were obtained from prepregs with a specific density of 1600 kg/m3. The tests were performed at room temperature. Scanning electron microscopy (SEM) was used to analyze the damage in the material during these tests, the mechanisms of their further damage progression and, the impact on the growth and growth rate of the initial crack in the material. The analysis of numerical results and micromechanical analysis confirmed the dominant role of the reinforcing structural element in the material in all performed tests. The obtained results are of great importance in the application of composite materials of such structures under different operating conditions and load regimes. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 451-03-68/2020-14/200135]

Comparison of Tensile Properties of Carbon/Epoxy Composite Materials with Different Fiber Orientation Using Digital Image Correlation

“…Known for its high stiffness to weight ratio and high strength to weight ratio [1][2][3][4][5][6][7], composite materials have a broad range of applications in aerospace [8][9][10], transportation [11,12], construction [13][14][15], energy [16,17], maritime [18,19], military [20,21], and civil applications [22][23][24][25][26][27]. Carbon fiber reinforced polymer (CFRP) has proved to be the most attractive for a wide variety of applications in recent years due to its remarkable properties and plain formability [28,29].…”