Impact protection structures with layered honeycomb and corrugated designs and methods for making the same
Presented are multilayer, fiber-reinforced impact protection structures with honeycomb-core or corrugated-layer designs, methods for making/using such structures, and vehicles with traction battery packs supported on skid plates fabricated from such structures. A multilayer impact protection structure includes a first layer with continuous fibers embedded in a polymeric matrix, and a second layer that is attached to the first layer and includes an elastomeric polymer. A third layer, which is attached to one side of the first layer opposite that of the second layer, includes a fiber-reinforced polymer honeycomb and/or corrugated structure. An optional fracture detection circuit is attached to the first or third layer, and is configured to detect a break in the impact protection structure. The corrugated structure may include multiple reinforcement ribs that are interposed within and substantially orthogonal to a series of mutually parallel, elongated ridges. Comparatively, the honeycomb structure includes a lattice of adjoining polygonal cells.
1. A multilayer impact protection structure, comprising:
a first layer including continuous fibers embedded in a polymeric matrix;
a second layer attached to a first side of the first layer and including an elastomeric polymer;
a third layer attached to a second side of the first layer, opposite the first side, and including a fiber-reinforced polymer (FRP) honeycomb and/or corrugated structure; and
a fracture detection circuit attached to the first layer or the third layer and configured to detect a break in the impact protection structure.
2. The impact protection structure of claim 1 , wherein the fracture detection circuit includes an engineered pattern of electrical wires laminated to or embedded within the first layer.
3. The impact protection structure of claim 1 , wherein the third layer includes the FRP corrugated structure, the FRP corrugated structure including a series of elongated, mutually parallel ridges.
4. The impact protection structure of claim 3 , wherein the series of elongated, mutually parallel ridges has a sinusoidal-waveform profile or a polygonal-waveform profile.
5. The impact protection structure of claim 3 , wherein each ridge in the series of mutually parallel ridges has a height of approximately 10-30 mm and a width of approximately 15-50 mm.
6. The impact protection structure of claim 3 , wherein the FRP corrugated structure further includes a plurality of reinforcement ribs interposed within and substantially orthogonal to the ridges.
7. The impact protection structure of claim 3 , wherein the FRP corrugated structure includes chopped fibers with a volume fraction of fiber of approximately 20-60%.
8. A multilayer impact protection structure comprising:
a first layer including continuous fibers embedded in a polymeric matrix;
a second layer attached to a first side of the first layer and including an elastomeric polymer; and
a third layer attached to a second side of the first layer, opposite the first side, and including a fiber-reinforced polymer (FRP) honeycomb structure, the FRP honeycomb structure including a lattice of adjoining polygonal cells.
9. The impact protection structure of claim 8 , further comprising a fracture detection circuit attached to the first layer or the third layer and configured to detect a break in the impact protection structure.
10. The impact protection structure of claim 8 , wherein the FRP honeycomb structure has an aerial weight of about 2.0 kg/m 2 to about 4.0 kg/m 2 and honeycomb walls with a variable wall thickness.
11. The impact protection structure of claim 8 , wherein the FRP honeycomb structure further includes a plurality of flanges projecting from discrete sections of the lattice of adjoining polygonal cells and adhered or welded to the first layer.
12. The impact protection structure of claim 8 , further comprising a fourth layer attached to the third layer on a side opposite that of the first layer and including continuous carbon and/or glass fibers embedded in a polymer matrix.
13. The impact protection structure of claim 12 , wherein the first layer has a first thickness about 50-500% thicker than a fourth thickness of the fourth layer.
14. The impact protection structure of claim 1 , wherein the first and third layers are simultaneously formed as a unitary, single-piece structure.
15. A multilayer impact protection structure, comprising:
a first layer including continuous fibers embedded in a polymeric matrix;
a second layer attached to a first side of the first layer and including an elastomeric polymer; and
a third layer attached to a second side of the first layer, opposite the first side, and including a fiber-reinforced polymer (FRP) honeycomb and/or corrugated structure,
wherein the first and third layers are formed as a unitary, single-piece structure.
16. The impact protection structure of claim 15 , further comprising a fracture detection circuit attached to the first layer or the third layer and configured to detect a break in the impact protection structure.
17. The impact protection structure of claim 15 , wherein the third layer includes the FRP corrugated structure, the FRP corrugated structure including a series of elongated, mutually parallel ridges.
18. The impact protection structure of claim 17 , wherein the series of elongated, mutually parallel ridges has a sinusoidal-waveform profile or a polygonal-waveform profile.
19. The impact protection structure of claim 15 , wherein the third layer includes the FRP honeycomb structure, the FRP honeycomb structure including a lattice of adjoining polygonal cells.
20. The impact protection structure of claim 19 , further comprising a fourth layer attached to the third layer on a side opposite that of the first layer, the fourth layer including continuous carbon and/or glass fibers embedded in a polymer matrix.