The objective of this project is to develop a hybrid, multifunctional composite material that improves the thermal and chemical stability, and surface durability of traditional carbon fiber reinforced polymer (CFRP) composites. By using a standard prepreg lay-up process, in which a flexible conductive ceramic thin layer is bonded directly onto the outmost layer of polymer composites to ensure the material integrity, a hybrid composite will be manufactured following the same procedure as standard CFRP composites without increasing extra manufacturing cost. The prepreg lay-up manufacturing steps to produce such a hybrid multifunctional composite material are listed as below: (1) spray release agent on the tooling surface; (2) apply the flexible thermally-conductive ceramic composite layer on the tooling surface over release agent; (3) prepreg multiple layers of carbon fiber sheets over the flexible ceramic composite layer; (4) co-cure the hybrid composite using the standard autoclave method. The produced hybrid composites can be used in harsher environment, (e.g., high temperature, moisture under load, ultraviolet radiation, corrosive chemicals). The manufacturing procedure is readily scalable. During experiment, we will implement process optimization/control during scale-up (size and geometric complexity) from coupon size to full-scale article according to application requirements.
Benefit: In this project, a hybrid multifunctional composite material will be created where the ceramic composite comprises the exterior layer of the material, for enhanced thermal/chemical stability and surface durability. The ceramic thin layer exhibits a high tensile strength (536 MPa) and has good flexibility. It can be bended 180 degree after 1000 times while the flexural strength and modulus are maintained at the similar value. From SEM images, no apparent cracks appear on the surface of the flexible ceramic composites after the flexibility test. For complex-shaped CFRP substrate geometry, the flexibility ensures that the ceramic thin layer contours to any curvature without crack or breakage. On another side, the ceramic thin layer has anisotropic thermal property the in plane thermal conductivity is 87 W/(mK) while the through thickness value is 2 W/(mK). The minimum surviving temperature is 1000oC. Therefore, environmental impacts (e.g., heat flow, corrosive fluid, etc.) will be quickly dissipated to surrounding area along the ceramic composite surface instead of penetrating deeper inside the carbon fiber reinforced polymer (CFRP) substrate. Such hybrid multifunctional composite materials can be applied in higher temperature and harsher environment, and can be utilized especially in naval and marine parts for enhanced strength and durability (e.g., salty and high moisture environment). Application examples are such as engines exhaust washer/nozzle section, with hot flow impact and pollution emissions (e.g., carbon monoxide, partially burned hydrocarbons, and nitric oxides), the ceramic composite skin layer provides good protection due to its high strength and high thermal conductivity properties.
Keywords: skin, skin, Ceramic matrix composites (CMC), heat flow, sand blasting, Polymers, carbon fiber reinforced polymer (CFRP), Ceramics, corrosive fluid
