Effect of PyC coating on mechanical properties of C_f/AZ91D composites

Abstract

The microstructure of high strength PAN-based T700 carbon fibre (C f ) with pyrolytic carbon (PyC) coating was characterised. Effects of PyC coating on the surface of carbon fibres, interface characteristics, and mechanical properties of C f /AZ91D composites were evaluated. The results showed that the carbon fibres with PyC coating had higher surface roughness and higher graphitisation which were beneficial to ease hazardous interface reaction. C f -PyC/ AZ91D composites with an optimal PyC coating that is about 150 nm thick and has low texture exhibited ultimate tensile strength of 416 MPa, which demonstrated 35% improvement compared with the C f /AZ91D composites. The increase of mechanical properties of C f -PyC/AZ91D composites could be ascribed to a synergistic effect of the rough C f surface interlocking, an optimum interfacial bonding between fibres and matrix, and protection of fibres from a corrosive attack of the aluminium element in the matrix.

Surface Coatings of Reinforcement Phases in Magnesium Matrix Composites: A Review

“…The fine and uniform precipitates and the nanocrystalline formed in the Mg matrix are beneficial to enhancing the MMCs. The coarse interfaces of the PyC adjust the stress on the interfaces and provide the desired bonding strength, which obviously improves the mechanical properties by more than 80% [23,60,61]. In addition, PyC coatings could improve the damping performance of AZ91-based MMCs between room temperature and 170 degrees [62].…”

Effect of pyrocarbon interphase texture and thickness on tensile damage and fracture in T‐700™ carbon fiber–reinforced silicon carbide minicomposites

“…PyC interphase is not only conducive to the toughening and strengthening of carbon fiber bundles, but can also significantly improve the mechanical properties of composites. [11][12][13][14] Ma et al investigated the microstructure and mechanical behavior of T-700™ C/SiC composites via precursor infiltration and pyrolysis. 15 The mechanical properties of C/SiC composite with PyC interphase were improved with higher flexural strength, flexural modulus, and shear strength.…”