INVESTIGATION OF THE COMPOSITE MATERIAL MICROSTRUCTURE AT THE STAGE OF CARBON-FIBER-REINFORCED POLYMER OBTAINING
The paper presents methods of the structure studying, methods of thin section preparations. A list of equipment and software used for thin sections preparation is described. The investigation object is the carbon fiber material. Material is obtained by press molding tabbed-tissue-piercing laying carcass previously impregnated by thermosetting phenol formaldehyde binder with followed polymerization. The studies of microstructure were conducted with metallographic inverted microscope METAM LP-42 for carbon fiber reinforced polymer samples in the reflected light by analogy with method applied in metallurgy at 50 <sup>x</sup>-1000 <sup>x</sup> magnification. The sample's microstructure photographing held a digital camera CAM V200 with a resolution of 1296×972. The compact digital camera for computer microscopes is installed in place of the microscope eyepiece without any additional devices and connected to a computer. This unit can be connected to all microscopes with eyepiece diameter 23,2 mm (mono, binocular, trinocular) without special adapters. The result of experimental research is qualitative analysis of the material structure. The research showed that the samples had a dense and uniform stacking of carbon filaments. In the structure there are also a small number of medium-sized elongated pores between threads (macropores) filled with binder. Macropores are distributed uniformly over the sample thickness. Distribution of the binder inside material is not uniform. Inside the material throughout the volume there are regions with not tight laying filaments. The space between threads is filled with a binder partially. There are numerous micropores free of binder.