# US 12,179,425 B2 · Metal plated additively manufactured plastic rotor shrouds and their method of manufacturing > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,179,425 B2 - Document ID: US12179425B2 - Status: Granted - Kind: B2 - Application number: 18/104,514 - Filed: 2023-02-01 - Published: 2024-08-01 - Granted: 2024-12-31 - Earliest claimed: 2023-02-01 - Assignees: Hamilton Sundstrand Corporation - Applicants: Hamilton Sundstrand Corporation - Inventors: Brent J. Merritt; Viktor Kilchyk - Web page: https://patentgrep.com/patent/US12179425B2 ## CPC - B29C 64/165: using a combination of solid and fluid materials, e.g. a powder selectively bound by a liquid binder, catalyst, inhibitor or energy absorber - F01D 5/282: {Selecting composite materials, e.g. blades with reinforcing filaments} - B29C 64/30: Auxiliary operations or equipment - B33Y 40/20: Post-treatment, e.g. curing, coating or polishing - B33Y 70/10: Composites of different types of material, e.g. mixtures of ceramics and polymers or mixtures of metals and biomaterials - B33Y 80/00: Products made by additive manufacturing - F01D 5/288: {Protective coatings for blades} - F01D 25/24: Casings (modified for heating or cooling F01D25/14); Casing parts, e.g. diaphragms, casing fastenings (casings for rotary machines or engines in general F16M {; special arrangements in stators dealing with breaking-off of part of rotor F01D21/045}) - F04D 29/023: {especially adapted for elastic fluid pumps} - F04D 29/4226: {Fan casings} - B29K 2305/00: Use of metals, their alloys or their compounds, as reinforcement - B29K 2995/0012: having particular thermal properties - B29L 2031/7504: {Turbines} - F05D 2220/323: for aircraft propulsion, e.g. jet engines - F05D 2230/30: with deposition of material - F05D 2230/31: Layer deposition - F05D 2230/90: Coating; Surface treatment - F05D 2300/43: Synthetic polymers, e.g. plastics; Rubber - F05D 2300/603: Composites; e.g. fibre-reinforced - F05D 2300/614: Fibres or filaments - 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) - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - B33Y: ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING - F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02) - 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 - B29L: INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract In one aspect, a rotor shroud for a rotary machine includes a disk portion extending along and oriented about a central axis of the rotary machine, a transition portion extending from the disk portion, and a flared portion extending axially from the transition portion. The disk portion, the transition portion, and the flared portion include a plastic substrate and metal plating disposed on at least apportion of an outer surface of the plastic substrate. The plastic substrate has a matrix material and fibers embedded in the matrix material. The fibers have a first coefficient of thermal expansion. The metal plating has a second coefficient of thermal expansion. The fibers are selected such that a bulk coefficient of thermal expansion of the plastic substrate at the outer surface of the plastic substrate substantially matches the second coefficient of thermal expansion of the metal plating. ## Claims ### Claim 1 A rotor shroud for a rotary machine comprising: a disk portion extending along and oriented about a central axis of the rotary machine; a transition portion extending from the disk portion; and a flared portion extending axially from the transition portion, the disk portion, the transition portion, and the flared portion together comprising: a plastic substrate, the plastic substrate comprising: a matrix material; and fibers embedded in the matrix material, the fibers having a first coefficient of thermal expansion; and a metal plating disposed on at least a portion of an outer surface of the plastic substrate, the metal plating having a second coefficient of thermal expansion, wherein the fibers are selected such that a bulk coefficient of thermal expansion of the plastic substrate at the outer surface of the plastic substrate matches the second coefficient of thermal expansion of the metal plating. ### Claim 2 (depends on 1) The rotor shroud of claim 1, wherein the matrix material has a third coefficient of thermal expansion, the third coefficient of thermal expansion greater than the first coefficient of thermal expansion of the fibers. ### Claim 3 (depends on 2) The rotor shroud of claim 2, wherein the first coefficient of thermal expansion of the fibers is less than the second coefficient of thermal expansion of the metal plating. ### Claim 4 (depends on 1) The rotor shroud of claim 1, wherein the fibers are selected from the group consisting of carbon, para-aramid, glass, metal, and combinations thereof. ### Claim 5 (depends on 4) The rotor shroud of claim 4, wherein the metal plating and the fibers are the same material. ### Claim 6 (depends on 1) The rotor shroud of claim 1, wherein a fiber density of the fibers embedded in the matrix material varies within the plastic substrate. ### Claim 7 (depends on 6) The rotor shroud of claim 6, wherein the plastic substrate comprises: a first region having a reduced fiber density; and one or more second regions having an increased fiber density, wherein the one or more second regions is a deflection region, a stress region, and/or an energy containment region of the rotor shroud, the deflection region subject to deflections during operation of the rotary machine, the stress region adapted to withstand higher stress than other regions of the rotor during operation of the rotary machine, and the energy containment region configured to contain energy of failed components of the rotary machine. ### Claim 8 (depends on 7) The rotor shroud of claim 7, wherein the stress region and the deflection region are a flange extending axially outward from the disk portion of the rotor shroud. ### Claim 9 (depends on 7) The rotor shroud of claim 7, wherein the stress region is a region surrounding a plurality of bolt holes through a radially outer portion of the disk portion of the rotor shroud, and/or wherein the stress is a region of the transition portion adjacent to the flared portion of the rotor shroud. ### Claim 10 (depends on 7) The rotor shroud of claim 7, wherein the energy containment region is a region of the transition portion adjacent a first side and a radially inner end of the rotor shroud. ### Claim 11 (depends on 6) The rotor shroud of claim 6, wherein an outer region disposed adjacent to the metal coating has an increased fiber density. ### Claim 12 (depends on 11) The rotor shroud of claim 11, wherein the fibers of the outer region protrude through the outer surface of the plastic substrate. ### Claim 13 (depends on 11) The rotor shroud of claim 11, wherein fibers of the outer region are angled with respect to the outer surface of the plastic substrate. ### Claim 14 A method of forming a rotor shroud for a turbomachine, the method comprising: forming, by an additive manufacturing process, a plastic substrate having an outer surface; impregnating, by the additive manufacturing process, the plastic substrate with fibers having a first coefficient of thermal expansion; and applying a metal plating to at least a portion of the outer surface of the plastic substrate, the metal plating having a second coefficient of thermal expansion; wherein the fibers are selected such that a bulk coefficient of thermal expansion of the plastic substrate at the outer surface of the plastic substrate matches the second coefficient of thermal expansion of the metal plating, wherein the plastic substrate and the metal plating together form the rotor shroud having a disk portion extending along and oriented about a central axis of the rotary machine, a transition portion extending from the disk portion, and a flared portion extending axially from the transition portion. ### Claim 15 (depends on 14) The method of claim 14, wherein the additive manufacturing process is 3D printing. ### Claim 16 (depends on 15) The method of claim 15, wherein the step of impregnating comprises selectively printing the fibers to vary a fiber density in the plastic substrate. ### Claim 17 (depends on 16) The method of claim 16, wherein the step of impregnating comprises: selectively printing fibers to form a region of increased fiber density adjacent to the portion of the outer surface of the plastic substrate to which the metal plating is applied; and/or selectively printing fibers at an angle relative to the portion of the outer surface to which the metal plating is applied. ### Claim 18 The method of 16, wherein the plastic of the plastic substrate has a third coefficient of thermal expansion, the third coefficient of thermal expansion greater than the first coefficient of thermal expansion of the fibers. ### Claim 19 The method of 18, wherein the first coefficient of thermal expansion of the fibers is less than the second coefficient of thermal expansion of the metal plating. ### Claim 20 (depends on 19) The method of claim 19, wherein the fibers are selected from the group consisting of carbon, para-aramid, glass, metal, and combinations thereof.