  Self-sensing composites performance largely relies on the sensing fillers
property and interface. Our previous work demonstrates that the microwires can
enable self-sensing composites but with limited damage detection capabilities.
Here, we propose an optimization strategy capitalizing on dual interfaces
formed between glass-coat and metallic core (inner interface) and epoxy matrix
(outer interface), which can be decoupled to serve different purposes when
experiencing stress; outer interfacial modification is successfully applied
with inner interface condition preserved to maintain the crucial circular
domain structure for better sensitivity. We found out that the damage detection
capability is prescribed by periodical structural integrity parameterized by
cracks number and location in the case of damaged wires; it can also be
optimized by stress transfer efficiency with silane treated interface in the
case of damaged matrix. The proposed self-sensing composites enabled by a
properly conditioned dual-interfaces are promising for real-time monitoring in
restricted and safety-critical environments.
