fig5

Figure 5. (A) Surface microstructures of domes, pyramids, or micro columns^[54]; (B) Multi-layer interlocking sandwich structure^[28]; (C) Filamentous mastoid structure array^[55]; (D) Gradient pyramid meta-surface structure^[56]; (E) Dynamic mechanical interlock interface^[57]; (F) Interfacial mechanical interlocking microstructure^[58].