Effect of different ceramic fillers filled with GF/PTFE on the tensile and compressive properties of the composites

Abstract

In this article, six ceramic-filled glass fiber (GF)/PTFE-based composites were fabricated using 15 wt.% mass fraction GF and 80 wt.% PTFE as matrix materials and 5 wt.% mass fraction ceramic materials such as Al2O3, MoS2, TiO2, BaSO4, hollow glass beads (HGB), and solid glass beads (SGB) as filler materials, respectively, at 44 MPa molding pressure and sintering temperature of 370°C. The tensile strength, elongation at break, and compressive strength at room temperature and 250°C were investigated for six composites. Finally, the surface morphology of the composites was characterized using the ultradeep field electron microscope. The results show that MoS2 has the best synergistic strengthening effect with GF in PTFE matrix, but the toughening effect is less obvious, so MoS2/GF/PTFE exhibits the maximum hardness (66) and tensile strength (18.16 MPa) and the minimum elongation at break (94.72%), while HGB/GF/PTFE composites exhibit the minimum hardness (61) and tensile strength (15.04 MPa) and the maximum elongation at break (360.36%). In addition, the MoS2/GF/PTFE exhibited the maximum compressive strength (9.29 MPa) at 250°C, but then the SGB/GF/PTFE composite exhibited the maximum compressive strength (24.28) at room temperature. A comprehensive analysis of the modification mechanism shows that the type, morphology, particle size, strength, and interfacial bonding with the PTFE matrix of the ceramic filler all influence the filling effect of the composite.