# US 11,440,246 B1 · Methods and systems for inspecting hierarchical powders and verifying the functionalization of powder surfaces > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,440,246 B1 - Document ID: US11440246B1 - Status: Granted - Kind: B1 - Application number: 17/121,627 - Filed: 2020-12-14 - Granted: 2022-09-13 - Earliest claimed: 2020-02-14 - Assignees: HRL Laboratories, LLC - Applicants: HRL Laboratories, LLC - Inventors: Darby Laplant; John H. Martin; Jacob Hundley; Julie Miller; Zak Eckel - Web page: https://patentgrep.com/patent/US11440246B1 ## CPC - B29C 64/153: using layers of powder being selectively joined, e.g. by selective laser sintering or melting - B33Y 70/00: Materials specially adapted for additive manufacturing - B22F 10/34: of powder characteristics, e.g. density, oxidation or flowability - B22F 1/052: characterised by a mixture of particles of different sizes or by the particle size distribution - B22F 1/054: Nanosized particles - B22F 1/102: Metallic powder coated with organic material - B22F 1/145: Chemical treatment, e.g. passivation or decarburisation - B22F 1/16: Metallic particles coated with a non-metal (coated with lubricating or binding agents or with organic material B22F1/10) - B22F 1/17: Metallic particles coated with metal - B22F 2999/00: Aspects linked to processes or compositions used in powder metallurgy - 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) - 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 - 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 - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract The present disclosure provides a methodology in which nanoparticle-coated microparticles are rapidly quality-checked for verification of surface functionalization of a commercial quantities of hierarchical powder. Some variations provide a method for inspecting surface-functionalized microparticles, comprising: selecting samples of hierarchical powders comprising microparticles and surface-coated nanoparticles; subjecting the hierarchical powders to a sample particle-size measurement; comparing the sample particle-size measurement to a baseline measurement; and determining the relative concentration of free nanoparticles, based on particle-size distributions. If the sample particle-size measurement is statistically equivalent to the baseline measurement, that is verification of complete surface functionalization. If the sample particle-size measurement is statistically different than the baseline measurement, then the baseline measurement is subtracted from the sample particle-size measurement, to determine the content of free nanoparticles. Optionally, the surface-coated nanoparticles are removed from the sample and additional particle-size distributions measured, to determine the content of original surface-coated nanoparticles, for additional quality control. ## Claims ### Claim 1 A method for inspecting surface-functionalized microparticles, said method comprising: (a) selecting at least one sample of hierarchical particle assemblies comprising microparticles and microparticle-surface-coated nanoparticles, wherein said microparticle-surface-coated nanoparticles are chemically and/or physically attached to said microparticles, and wherein, when surface functionalization is not complete, said sample further comprises free nanoparticles that are not chemically or physically attached to said microparticles; (b) obtaining a baseline particle-size measurement of nanoparticle-free microparticles, thereby providing a microparticle particle-size distribution; (c) subjecting said hierarchical particle assemblies to a sample particle-size measurement, thereby providing a sample particle-size distribution; (d) comparing said sample particle-size measurement to said baseline particle-size measurement; (e) if said sample particle-size measurement is statistically equivalent to said baseline particle-size measurement, then providing verification that there is complete surface functionalization due to the absence of said free nanoparticles; (f) if said sample particle-size measurement is statistically different than said baseline particle-size measurement, then subtracting said baseline particle-size measurement from said sample particle-size measurement, to calculate a free-nanoparticle particle-size distribution; and (g) determining a relative concentration of said free nanoparticles within said sample, based at least on said free-nanoparticle particle-size distribution. ### Claim 2 (depends on 1) The method of claim 1, wherein said sample particle-size measurement and said baseline particle-size measurement utilize a particle-size measurement technique selected from the group consisting of laser diffraction, dynamic light scattering, diffusing wave spectroscopy, static optical imaging, and dynamic optical imaging. ### Claim 3 (depends on 2) The method of claim 2, wherein said particle-size measurement technique is laser diffraction. ### Claim 4 (depends on 1) The method of claim 1, wherein said sample particle-size measurement and said baseline particle-size measurement are conducted in a gas. ### Claim 5 (depends on 1) The method of claim 1, wherein said sample particle-size measurement and said baseline particle-size measurement are conducted in a liquid media. ### Claim 6 (depends on 1) The method of claim 1, wherein a relative concentration of said microparticle-surface-coated nanoparticles is determined by subtracting said relative concentration of said free nanoparticles from a known or estimated concentration of total nanoparticles within said sample, wherein said microparticle-surface-coated nanoparticles are chemically and/or physically attached to said microparticles. ### Claim 7 (depends on 1) The method of claim 1, wherein a relative concentration of said surface-coated nanoparticles is determined by additional steps of: (h) subjecting said sample to a surface defunctionalization to detach said microparticle-surface-coated nanoparticles from said microparticles, thereby generating disassembled microparticles and disassembled nanoparticles; (i) subjecting said disassembled microparticles and said disassembled nanoparticles to a disassembled-particle-size measurement, thereby providing a disassembled-particle-size distribution; (j) subtracting said microparticle particle-size distribution and said free-nanoparticle particle-size distribution from said disassembled-particle-size distribution, to calculate a disassembled-nanoparticle particle-size distribution that characterizes particle sizes of said disassembled nanoparticles; and (k) determining a relative concentration of said microparticle-surface-coated nanoparticles within said sample, based at least on said disassembled-nanoparticle particle-size distribution obtained in step (j), wherein said microparticle-surface-coated nanoparticles are chemically and/or physically attached to said microparticles. ### Claim 8 (depends on 7) The method of claim 7, wherein in step (h), said surface defunctionalization detaches essentially all of said microparticle-surface-coated nanoparticles from said microparticles. ### Claim 9 (depends on 7) The method of claim 7, wherein in step (h), said surface defunctionalization detaches less than all of said microparticle-surface-coated nanoparticles from said microparticles; and wherein nanoparticle removal efficiency of said surface defunctionalization is known or estimated. ### Claim 10 (depends on 7) The method of claim 7, wherein said surface defunctionalization is carried out in a vapor defunctionalization media. ### Claim 11 (depends on 7) The method of claim 7, wherein said surface defunctionalization is carried out in a liquid defunctionalization media. ### Claim 12 (depends on 11) The method of claim 11, wherein in step (b), said baseline particle-size measurement of nanoparticle-free microparticles is conducted in said liquid defunctionalization media. ### Claim 13 (depends on 11) The method of claim 11, wherein said liquid defunctionalization media contains water, an organic solvent, an inorganic solvent, an ionic liquid, or a combination thereof. ### Claim 14 (depends on 13) The method of claim 13, wherein said liquid defunctionalization media further contains a salt, a surfactant, an organic additive, an inorganic additive, or a combination thereof. ### Claim 15 (depends on 7) The method of claim 7, wherein said surface defunctionalization utilizes agitation, sonication, or a combination thereof. ### Claim 16 (depends on 7) The method of claim 7, wherein said surface defunctionalization utilizes centrifugation, decantation, or a combination thereof. ### Claim 17 (depends on 7) The method of claim 7, wherein said surface defunctionalization utilizes filtration, membrane separation, or a combination thereof. ### Claim 18 (depends on 7) The method of claim 7, wherein said surface defunctionalization is carried out in a liquid defunctionalization media, and wherein said disassembled microparticles and said disassembled nanoparticles are dried for further analysis. ### Claim 19 (depends on 1) The method of claim 1, wherein said at least one sample includes at least two distinct samples from a batch of said hierarchical particle assemblies. ### Claim 20 (depends on 1) The method of claim 1, wherein said at least one sample includes at least three distinct samples from a batch of said hierarchical particle assemblies.