The influence of interlaminar microstructure on the induction heating patterns of CFRP laminates

Abstract

The impact of interlaminar microstructure on the induction heating patterns of CFRP laminates is investigated using thermography technique. Different consolidation methods were used to obtain the varying interlaminar distances. When excited by a circular induction coil, the induction heating pattern of laminates shifted from a circular to a rectangular shape as the interlaminar distance increased. The shift in the heating patterns is caused by the increase in fiber separations at the interface, which leads to fewer electrical contacts. The effect of varying interlaminar distance was modeled as an effective through-thickness electrical conductivity in the numerical model. When the separation between the fibers increased from 8 ± 3.6 μm to 15.3 ± 3.8 μm, the ratio of junction heating to fiber heating increased from 60% to 135%.