For major load-bearing structures such as the blade main spar and shear web
The core material is direct-twist roving for winding/weaving, which provides the primary strength and stiffness.
For large-area infusion areas such as blade housings and engine cowlings
By combining chopped strand mat (EEMC series) with continuous filament mat (CFM601 series), rapid impregnation and balanced mechanical properties are achieved.
To improve interlaminar toughness and prevent cracking
Needle mat is incorporated into critical areas; its three-dimensional structure effectively inhibits crack propagation.
For the final surface layers of blade leading edges, housings, etc.
Using surface veil to form a dense, resin-rich layer that provides ultimate protection.
