# US 2014/0193608 A1 · Structural composite panel with metallic foam core > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0193608 A1 - Document ID: US20140193608A1 - Status: Published application - Kind: A1 - Application number: 13/737,299 - Filed: 2013-01-09 - Published: 2014-07-10 - Earliest claimed: 2013-01-09 - Assignees: GM Global Technology Operations LLC - Applicants: GM Global Technology Operations LLC - Inventors: Joseph M. Polewarczyk; Paul E. Krajewski - Web page: https://patentgrep.com/patent/US20140193608A1 ## CPC - B32B 5/18: characterised by features of a layer {of} foamed material - B29C 70/088: {and with one or more layers of non-plastics material or non-specified material, e.g. supports} - B29D 99/001: {Producing wall or panel-like structures, e.g. for hulls, fuselages, or buildings (articles with hollow walls B29D24/00)} - B29D 99/0021: {provided with plain or filled structures, e.g. cores, placed between two or more plates or sheets, e.g. in a matrix} - B32B 5/245: {another layer next to it being a foam layer} - B32B 37/185: {Laminating sheets, panels or inserts between two discrete plastic layers} - B32B 38/0012: {Mechanical treatment, e.g. roughening, deforming, stretching} - B29K 2705/02: Aluminium - B29K 2715/003: Cellular or porous - B32B 38/10: Removing layers, or parts of layers, mechanically or chemically - B32B 2250/40: Symmetrical or sandwich layers, e.g. ABA, ABCBA, ABCCBA - B32B 2260/023: Two or more layers - B32B 2260/046: Synthetic resin - B32B 2262/106: Carbon fibres, e.g. graphite fibres - B32B 2266/045: Metal - B32B 2266/08: Closed cell foam - B32B 2305/022: Foam - B32B 2305/076: Prepregs - B32B 2307/54: Yield strength; Tensile strength - B32B 2311/00: Metals, their alloys or their compounds - B32B 2607/00: Walls, panels - Y10T 156/10: Methods of surface bonding and/or assembly therefor - Y10T 156/1039: Surface deformation only of sandwich or lamina [e.g., embossed panels] - Y10T 156/1043: Subsequent to assembly - Y10T 156/1052: with cutting, punching, tearing or severing - Y10T 156/1062: Prior to assembly - Y10T 428/24331: including nonapertured component - Y10T 428/24347: From both sides - Y10T 428/24997: Of metal-containing material - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - B29D: PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE (making granules B29B9/00; making preforms B29B11/00) - B29K: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR {MOULDS, } REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A structural panel includes a closed-cell foam core formed of a metallic material; a first carbon-fiber panel bonded to a first side of the closed-cell foam core; and a second carbon-fiber panel bonded to a second side of the closed-cell foam core such that the foam core is disposed between the first carbon-fiber panel and the second carbon-fiber panel. ## Claims ### Claim 1 A structural panel comprising: a closed-cell foam core formed of a metallic material; a first carbon-fiber panel bonded to a first side of the closed-cell foam core; and a second carbon-fiber panel bonded to a second side of the closed-cell foam core, such that the foam core is disposed between the first carbon-fiber panel and the second carbon-fiber panel. ### Claim 2 (depends on 1) The structural panel of claim 1, wherein the foam core includes a perimeter structure and a stiffening rib; and wherein the foam core defines a plurality of weight-reducing voids between the perimeter structure and the stiffening rib. ### Claim 3 (depends on 2) The structural panel of claim 2, wherein the first carbon-fiber panel and the second carbon-fiber panel are drawn into each of the plurality of voids through vacuum forming. ### Claim 4 (depends on 2) The structural panel of claim 2, wherein the perimeter structure of the foam core aligns with, and is interior to the perimeter of each of the first carbon-fiber panel and the second carbon-fiber panel. ### Claim 5 (depends on 1) The structural panel of claim 1, wherein the closed-cell foam core is aluminum. ### Claim 6 (depends on 1) The structural panel of claim 1, wherein the closed-cell foam core includes a porous cellular structure; and wherein the average size of each pore of the porous cellular structure is between approximately 1 mm and approximately 8 mm. ### Claim 7 A method of forming a structural composite panel comprising: positioning a closed-cell foam core between a first carbon-fiber panel and a second carbon-fiber panel, the closed-cell foam core being formed from a metallic material; bonding each of the respective first carbon-fiber panel and second carbon-fiber panel to the closed-cell foam core. ### Claim 8 (depends on 7) The method of claim 7, further comprising machining a plurality of voids in the closed-cell foam core; wherein the machined foam core includes a perimeter structure and a stiffening rib; and wherein the plurality of voids are defined between the perimeter structure and the stiffening rib. ### Claim 9 (depends on 8) The method of claim 8, wherein positioning a closed-cell foam core between a first carbon-fiber panel and a second carbon-fiber panel is such that the perimeter structure of the foam core aligns with, and is interior to the perimeter of each of the first carbon-fiber panel and the second carbon-fiber panel. ### Claim 10 (depends on 8) The method of claim 8, wherein bonding each of the respective first carbon-fiber panel and second carbon-fiber panel to the closed-cell foam core includes: heating each of the respective first and second carbon-fiber panels; and applying pressure to each of the respective first and second carbon-fiber panels such that each of the respective first and second carbon-fiber panels are deformed into each of the plurality of machined voids. ### Claim 11 (depends on 10) The method of claim 10, wherein each of the respective first and second carbon-fiber panels are pre-impregnated panels including a partially cured resin disposed about a fiber sheet; and wherein heating each of the respective first and second carbon-fiber panels is operative to fully cure the partially cured resin. ### Claim 12 (depends on 7) The method of claim 7, wherein the closed-cell foam core is aluminum. ### Claim 13 (depends on 7) The method of claim 7, wherein the closed-cell foam core includes a porous cellular structure; and wherein the average size of each pore of the porous cellular structure is between approximately 1 mm and approximately 8 mm. ### Claim 14 A structural panel comprising: a closed-cell foam core formed of a metallic material, the foam core including a perimeter structure and a stiffening rib, and defining a plurality of voids between the perimeter structure and the stiffening rib; a first carbon-fiber panel bonded to a first side of the closed-cell foam core; and a second carbon-fiber panel bonded to a second side of the closed-cell foam core, such that the foam core is disposed between the first carbon-fiber panel and the second carbon-fiber panel. ### Claim 15 (depends on 14) The structural panel of claim 14, wherein the first carbon-fiber panel and the second carbon-fiber panel are drawn into each of the plurality of voids through vacuum forming. ### Claim 16 (depends on 14) The structural panel of claim 14, wherein the perimeter structure of the foam core aligns with, and is interior to the perimeter of each of the first carbon-fiber panel and the second carbon-fiber panel. ### Claim 17 (depends on 14) The structural panel of claim 14, wherein the closed-cell foam core is aluminum. ### Claim 18 (depends on 14) The structural panel of claim 14, wherein the closed-cell foam core includes a porous cellular structure; and wherein the average size of each pore of the porous cellular structure is between approximately 1 mm and approximately 8 mm.