2021 Volume 57 Issue 4 Pages 139-144
In situ analysis of the residual stress in a glass fiber-reinforced resole-type phenolic resin and aluminum
foil composite material during curing and thermal-cycle testing was performed via X-ray diffraction
measurements of Al（422）-plane using the sin2 Ψ method. In the curing process, the residual stress at the
resin and aluminum interface changed due to the difference in the magnitude of the thermal expansion and
contraction between them, which arose by the difference in the coefficient of the thermal expansion（ CTE）,
and a cure-shrinkage of the resin. Additionally, the behavior of the stress change was greatly influenced by the
glass-transition of the resin which involved a large CTE change of the resin. The stress-free temperature was
successfully determined by the stress-change during the thermal cycle, in which the resin-aluminum interface
in the investigated composite was in a stress-free state at 160 ℃. The continuous stress change during curing
showed that the residual stress in the cured composite was strongly affected by the stress state before curing,
suggesting that the stress-free temperature could be controlled by the composite molding process.
