Study of structure of carbon fiber- and metal-reinforced plastics during change in temperature and pressure

Conclusions

• 1. Studies on the microstructure of CMP by optical and electron microscopic x-ray diffraction methods showed that during thermal loading in the 20-1000°C range, at a constant heating rate, an increase in argon pressure to 1.5 MPa does not cause structural changes in the filling of the composite, i.e., graphitized cloth and tungsten wire mesh.

• 2. The carrier for the structural transformations in CMP with increase in temperature and pressure is the matrix, the phenol resin. It was shown that increase in pressure of a neutral gaseous medium favors the contraction of the CMP samples irrespective of the direction of cut-out. By the optical method it was found that the porosity of the composite samples decreases under pressure by 70–75%, compared with the initial state.

• 3. From an analysis of the regularities of thermal deformation of CMP, confirmed by gravimetric and structural studies, it was found that increase in pressure from 0.025 to 1.5 MPa when the samples are heated at constant rate slows the thermal degradation processes in carbon fiber- and metal-reinforced plastic. On repeated thermal loading in an argon atmosphere of CMP samples previously tested under pressure, the thermal degradation processes in the material develop more intensely the higher the pressure was during the first heating.