| 摘要 |
A method of structural health monitoring a composite structure 11 comprising at least one thermal element 18, comprises the steps of applying a stimulus to cause heating of said thermal element, removing the stimulus, and measuring the electrical resistance of said element as a function of time, to provide a thermal decay profile. The thermal decay profile may be monitored and compared to a library of reference thermal decay profiles, any changes being indicative of cracks, delamination, debonding or material changes. The thermal element is preferably electrically isolated from the fibre plys and may be an electrically and thermally conductive tow such as carbon fibre or metal wire. A detector element 20 may be located proximate to the thermal element; the electrical resistance of the detector element as a function of time providing a detector element thermal decay profile. Preferably, the thermal element and detector element may be located either side of a bonded joint line 16. A composite material comprising at least one thermal element electrically isolated from at least one fibre ply and encapsulated in cured resin binder matrix is also provided. |
