# US 10,118,226 B2 · Method for manufacturing an asymmetric component using additive manufacturing > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,118,226 B2 - Document ID: US10118226B2 - Status: Granted - Kind: B2 - Application number: 14/783,584 - Filed: 2014-04-01 - Published: 2016-03-03 - Granted: 2018-11-06 - Earliest claimed: 2013-04-10 - Assignees: Safran Aircraft Engines - Applicants: Safran Aircraft Engines - Inventors: Cyrille Baudimont - Web page: https://patentgrep.com/patent/US10118226B2 ## CPC - B29C 64/153: using layers of powder being selectively joined, e.g. by selective laser sintering or melting - B22F 3/24: After-treatment of workpieces or articles {(B22F3/1146 takes precedence)} - B22F 10/28: Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM] - B22F 10/40: Structures for supporting workpieces or articles during manufacture and removed afterwards - B22F 10/80: Data acquisition or data processing - B23K 26/342: Build-up welding - B29C 64/40: Structures for supporting 3D objects during manufacture and intended to be sacrificed after completion thereof - B33Y 40/20: Post-treatment, e.g. curing, coating or polishing - B22F 5/04: of turbine blades - B22F 10/368: Temperature or temperature gradient, e.g. temperature of the melt pool - B22F 2003/247: {Removing material: carving, cleaning, grinding, hobbing, honing, lapping, polishing, milling, shaving, skiving, turning the surface} - B33Y 10/00: Processes of additive manufacturing - Y02P 10/25: Process efficiency - 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) - B22F: WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER (making alloys by powder metallurgy C22C); APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER - B23K: SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM - 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 - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract A method of fabricating a part by additive fabrication, in particular by melting or sintering particles of powder by means of a high energy beam. The method includes supplying a digital model of a part to be fabricated; orienting the model relative to a construction direction for constructing the part; modifying the model by adding a sacrificial balancing fraction configured so as to balance the residual stresses that appear in the part while it is being fabricated; making a rough part layer by layer using an additive fabrication technique on the basis of the model as modified in this way, the layers being stacked in the construction direction; and using a material-removal method to eliminate the sacrificial portion from the rough part as results from the sacrificial balancing fraction of the model, thereby obtaining the part that is to be fabricated. ## Claims ### Claim 1 A method of fabricating a part by additive fabrication, the part to be fabricated possessing an asymmetrical portion, the method comprising: supplying a digital model of a part to be fabricated; orienting the digital model relative to a construction direction for constructing the part; modifying the digital model by adding a sacrificial balancing fraction configured so as to balance residual stresses that appear in the part while fabricating the part; making a rough part layer by layer using an additive fabrication technique based on the modified digital model, said layers being stacked in the construction direction, the rough part including a sacrificial portion corresponding to the sacrificial balancing fraction of the modified digital model; and eliminating the sacrificial portion from the rough part using a material removal method to obtain said part that is to be fabricated; wherein the sacrificial balancing fraction is configured in such a manner that the sacrificial portion of the rough part possesses mass lying in a range 70% to 130% of a mass of the asymmetrical portion. ### Claim 2 (depends on 1) A method according to claim 1, wherein the sacrificial balancing fraction is configured so that the sacrificial portion of the rough part possesses mass lies in a range 90% to 110% of the mass of the asymmetrical portion. ### Claim 3 (depends on 2) A method according to claim 2, wherein the sacrificial balancing fraction is added over a height substantially equivalent to a height of the asymmetrical portion. ### Claim 4 (depends on 2) A method according to claim 2, wherein the sacrificial balancing fraction is configured in such a manner that the resulting sacrificial portion is constructed opposite from the asymmetrical portion relative to the rough part. ### Claim 5 (depends on 2) A method according to claim 2, wherein the sacrificial balancing fraction is added so as to provide the model with at least one additional element of symmetry. ### Claim 6 (depends on 2) A method according to claim 2, wherein the sacrificial balancing fraction is configured in such a manner that the sacrificial portion of the rough part is symmetrical to the asymmetrical portion relative to a plane, said plane being a plane of symmetry of the rough part. ### Claim 7 (depends on 2) A method according to claim 2, wherein the modifying the digital model includes a step of defining an equilibrium plane parallel to the construction direction and corresponding to a plane of symmetry that the digital model would have if the digital model did not have its asymmetrical portion corresponding to the asymmetrical portion of the part. ### Claim 8 (depends on 7) A method according to claim 7, wherein the modifying the digital model includes adding a balancing segment to the digital model in each layer perpendicular to the construction direction, the balancing segment restoring symmetry to the layer under consideration of the digital model relative to the equilibrium plane. ### Claim 9 (depends on 7) A method according to claim 7, wherein the part to be fabricated is a blading part having a leading edge, a trailing edge, and an airfoil; the digital model of the blading part is oriented in such a manner that its leading edge or its trailing edge faces towards the construction table; and the equilibrium plane of the blading part intersects the blading part substantially halfway along the airfoil. ### Claim 10 (depends on 1) A method according to claim 1, wherein said additive fabrication technique is a method of fabrication by selecting melting or selecting sintering of beds of powder, or a method of fabrication by powder projection. ### Claim 11 (depends on 1) A method according to claim 1, wherein during the orienting, the model is oriented so as to minimize at least one of a number of fabrication supports and sizes of the fabrication supports. ### Claim 12 (depends on 1) A method according to claim 1, wherein the part to be fabricated is a blade comprising an airfoil and a root provided at an end of the airfoil, the airfoil including a leading edge and a trailing edge, and wherein the root of the blade is the asymmetric portion.