Thermal response and pyrolysis behavior of carbon fiber/phthalonitrile composites under one-sided butane flame heating: Experimental and numerical analysis

The present work innovatively investigates the one-sided flame heating thermal response and pyrolysis behavior of carbon fiber/phthalonitrile (Cf/PN) composite laminates. The effectiveness of the Abaqus/UMATHT subroutine in studying the temperature and reaction mechanism-dependent material thermal performance is proved. A numerical model which accounts for the correction of pyrolysis depth and multi-stage pyrolysis kinetics parameters is established to generate massive data to replace repeated experiments. By analyzing the temperature and temperature rise rate distribution, the total mass loss ratio, and the post-heating micromorphology in the thickness section, the pyrolysis characteristics of the material are discussed. Finally, the rear surface temperatures corresponding to different surface heat flux, specimen thickness and heating time are numerically predicted to provide potential engineering guidance for the application of phthalonitrile composite materials in thermal protection and load-bearing integrated structures.