Effect of Carbonization Heating Rate, Microstructure, and Lay-Up on the Interlaminar Tensile Properties of a Two-Dimensional Carbon-Carbon Composite

Abstract

A study of the effect of the carbonization heating rate, initial phenolic microstructure, and lamination lay-up on the interlaminar tensile (ILT) stiffness and strength (matrix-dominated properties) of two-dimensional carbon-carbon was performed. It was found that the heating rate (2-50°C/hr) during first carbonization did not have any appreciable effect on the final ILT strength of the composite. The quasi-isotropic lay-up produced thicker, less dense laminate than warp-aligned due to less efficient packing of the weaves but yield higher interlaminar tensile strength; probably due to formation of better matrix microstructure than warp-aligned laminates. Overall, the initial laminate quality (porosity) was found to be not important on the final properties; the carbonization and densification processes was found to heal significant amounts of original defects.