Printing methods and systems for additive manufacturing including in situ material regeneration

Abstract

A method and system for 3D printing is provided. [Solution] A method for 3D printing includes the steps of creating at least two separate sections of powder on a substrate, segmenting the substrate to separate the at least two separate sections of powder, compressing the powder on the segment of the substrate, removing loose / uncompressed powder from the segment of the substrate, creating a printed / processed layer by performing one or more of a printing process or processing operation on the segment of the substrate, and transferring the printed / processed layer from the segment of the substrate to a build platform.

Description

[Technical field]

[0001] The present disclosure relates to improved printing methods and systems for additive manufacturing (AM) processes, including performing parts of the process on a continuous substrate and performing parts of the process using segments of the substrate mounted on a carrier frame. The present disclosure also relates to in situ material regeneration methods and systems that enable recovery, reconditioning, and reuse of used materials, such as powders and / or liquids collected from the AM process, thus increasing material utilization efficiency and reducing manufacturing costs. [Background technology]

[0002] In a typical AM operation, layers are built on top of each other, or they are built on a conveyor belt, and in the final stage they are stacked on top of each other. For example, in current binder jet 3D printing, a powder layer of build material is deposited on a powder bed or substrate, followed by jetting a liquid binder onto the deposited powder layer to define the printed pattern. In this process, typically, a large amount of excess unbound build material powder is collected. Build material powder can be expensive, and therefore the collected used powder should preferably not be discarded as waste. Similarly, in inkjet 3D printing or jetted material 3D printing processes, a large amount of used liquids, such as solvents and inks, may be collected, which cannot be discarded as waste. However, reclamation of used powders and / or liquids by external sources can increase both the time and cost for manufacturing. Therefore, there is a need to provide an effective on-site material reclamation system to collect, recondition, and reuse used powders and liquids. There is also a need to provide improved transport of layers of powder individually through the various stations and to facilitate removal of the layers of processed powder from the substrate (base material) to which they are attached after processing at the various stations to provide improved stacking of layers to build a multi-layer stack product. Summary of the Invention

[0003] In one embodiment, a method includes depositing powder on a substrate at a powder deposition station, removing a first portion of the powder to create a clean portion of the substrate between the portions of the deposited powder, moving the portions of the deposited powder remaining on the substrate to a wetting station where the powder is wetted with a wetting agent, passing the wetted portions of the deposited powder through a compression station to compress the powder, cutting the substrate at the clean portions to create substrate segments each including one of the portions of the deposited powder, transferring the substrate segments with the deposited powder mounted thereon to respective carrier frames, transferring the substrate segments with the deposited powder mounted thereon to respective carrier frames, moving the substrate segments to a binder jetting station where a binder is deposited on the powder, and moving the carrier frame with the substrate segments with the layers mounted thereon to a lamination station to laminate the layers individually onto one another to form a multi-layer product.

[0004] In another embodiment, a method for 3D printing includes creating at least two separate sections of powder on a substrate, segmenting the substrate to separate the at least two separate sections of powder, compressing the powder on the substrate segment, removing loose / uncompressed powder from the substrate segment, creating a printed / processed layer by performing one or more of a printing process or processing operation on the substrate segment, and transferring the printed / processed layer from the substrate segment to a build platform.

[0005] In another embodiment, a 3D printing system includes a powder deposition station configured to deposit powder on the continuous substrate; a powder removal station configured to create at least two adjacent individual sections of powder on the continuous substrate separated by a powder-free clean strip of the continuous substrate; a cutting station configured to cut the continuous substrate at the clean strip of the continuous substrate to segment the continuous substrate into individual substrate segments to separate at least two individual sections of powder each formed on adjacent segments of the individual substrate segments; a transfer station configured to transfer each individual substrate segment onto a corresponding individual carrier frame; an inversion station configured to invert the carrier frame such that the two individual sections of powder are suspended from each individual substrate segment on which they are deposited; and a stacking station configured to receive and stack the individual sections of powder from the respective carrier frames.

[0006] The drawings illustrate one or more embodiments in accordance with the present teachings, by way of example only, and not by way of limitation. In the drawings, like reference numbers refer to the same or similar elements. It should also be understood that the drawings are not necessarily to scale. [Brief description of the drawings]

[0007] [Figure 1a] FIG. 1 illustrates an overall printing system for performing a portion of a printing process on a continuous substrate, and a portion of the process performed on a substrate segment supported on a carrier frame, according to an aspect of the present disclosure. [Figure 1b] FIG. 1b illustrates how one or more sensing / monitoring modules are utilized to control the operation of the printing process of FIG. 1a. [Figure 1c] FIG. 1b illustrates how one or more sensing / monitoring modules are utilized to control the operation of the printing process of FIG. 1a. [Diagram 2]FIG. 1 illustrates an overall flow chart of a printing process using powder deposited on a substrate, including in situ powder collection and reclamation, according to an embodiment of the present disclosure. [Diagram 3] FIG. 1 illustrates a flowchart of an in-situ powder collection and reclamation method for multiple printing systems using powder deposition, according to aspects of the present disclosure. [Figure 4] FIG. 3 illustrates a method for in-situ clean powder collection and reclamation at an early stage of a printing system using the powder deposition shown in FIG. 2 according to an embodiment of the present disclosure. [Diagram 5] 3 illustrates a method for in situ collection and reclamation of wetting agent-contaminated powder at an intermediate stage of a printing system using the powder deposition shown in FIG. 2 according to an embodiment of the present disclosure. [Figure 6] 3 illustrates a method for in-situ binder-contaminated powder collection and reclamation at the end of the printing system using powder deposition as shown in FIG. 2 according to an embodiment of the present disclosure. [Figure 7] FIG. 1 illustrates a flow chart of a powder regeneration method for a printing system using powder deposition, according to an aspect of the present disclosure. [Figure 8] FIG. 13 illustrates a flow chart of an alternative powder regeneration method for a printing system using powder deposition, according to an aspect of the present disclosure. [Figure 9] FIG. 1 illustrates an overall flow chart of a printing process using powder deposited on a substrate, including in-situ wetting agent / liquid collection and regeneration, according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] In the following detailed description, numerous specific details are set forth by way of example to provide a thorough understanding of the disclosed subject matter. However, upon reading this disclosure, it may become apparent to one skilled in the art that one or more of the disclosed aspects may be practiced without such details. Furthermore, the description of various exemplary embodiments according to the present disclosure may include references to or to one or more known techniques or operations, and such references may be at a relatively high level to avoid obscuring various concepts, aspects, and features thereof with details that are not specific to the present disclosure and are not necessary to fully understand the present disclosure.

[0009] The present disclosure provides an improved AM system, e.g., a 3D printing system, in which an initial portion of the 3D printing process is performed on a continuous substrate (base material), after which the substrate is cut into segments, each segment including a layer formed of a portion of printed powder mounted thereon, the segments each being mounted on an individual carrier frame, and the layers undergo further processing while mounted on the carrier frame. Following this, the individual layers are transferred from the individual carrier frames to a stack of previously processed layers, e.g., on a build platform.

[0010] Referring to FIG. 1a, an overall system 100 for performing an early portion of a 3D printing process 105 on a continuous substrate and a later portion 110 of the process with individual layers mounted on a carrier frame is shown. As seen in FIG. 1a, the continuous substrate portion 105 of the system 100 includes a powder deposition station 120 where powder is deposited on a moving substrate, and a powder removal station 125 where powder is removed to create a clean strip of substrate separating adjacent sections of powder that will become layers of powder for stacking at a later stage of the process. The clean strip of substrate is used to cut the substrate into segments at a later stage of the process, with each segment having a portion of the powder that will be formed into a powder layer for stacking. The continuous substrate portion of the system can also include a lubrication / wetting station 130, which wets the deposited powder with a wetting agent to prevent the powder from adhering to the calender rollers in the calendering or compacting station 135, which is used in the process to compact the wetted powder before further processing. This allows for high packing densities (e.g., greater than 30%) that cannot be achieved with normal AM systems. The continuous substrate may be formed, for example, from Mylar, although other materials may be used.

[0011] 1a, the next station in the system may be a (laser) cutting / segmenting station 140 that cuts the substrate into segments for further processing individually as layers on segments, rather than processing adjacent portions of powder on a continuous substrate. Although FIG. 1a shows that the cutting station 140 uses laser cutting, other cutting techniques may be used if desired.

[0012] Still referring to FIG. 1a, a later stage 110 of the 3D printing process is performed after the transfer of the individual substrate segments to their corresponding individual carrier frames at the transfer station 145. A suitable carrier frame for this purpose is described in the applicant's related application entitled "Carrier Plate and Method of Use Thereof" (U.S. Patent Application No. 18 / 074,298), filed December 2, 2022. After segmentation, the wetting agent applied at the lubrication / wetting station can be removed at the wetting agent drying station 150. Sections of the layer on the substrate segment are then sent to the binder jetting and drying station 155, where a binder is applied to the individual layers of powder on the substrate segment, followed by drying of the binder at the same station. Alternatively, binder jetting can be performed at one station and binder drying can be performed at another station further downstream in the processing line.

[0013] In the embodiment shown in FIG. 1a, prior to further processing, the carrier frame is inverted at an inversion station 160, which rotates the carrier frame 180 degrees so that the layer of powder mounted on the carrier frame is suspended upside down from the corresponding substrate segment mounted on the carrier frame. In this way, the looser / uncompressed powder is impacted away from the substrate. In the embodiment shown in FIG. 1a, after inverting the carrier frame at the inversion station, excess powder or unpatterned portions of powder (i.e., powder that has not been subjected to binder jetting) can also be removed at a (laser) powder removal station 165. Applicant's related application entitled "Method and Apparatus for Powder Removal in an Additive Manufacturing System" filed on January 11, 2023 (U.S. Patent Application No. 18 / 152,854) describes features of a laser powder removal station for this purpose. In other embodiments, inversion of the carrier frame may not be required or alternative methods for removing unpatterned portions of powder may be utilized.

[0014] Finally, after removing excess powder, the carrier plate with the substrate segments with the individual layers of compressed and patterned powder thereon is passed to other processing stations, such as, for example, the material (ink) jetting and drying station 170. In some embodiments, the carrier frame may be flipped 180 degrees so that the layer of powder being processed faces up. In alternative implementations, the ink jetting and drying steps can be performed in two separate stations. In still other embodiments, the carrier plate with the substrate segments can be passed to other processing stations that are not printing stations. For example, the processing station can pick up and place elements, such as conductive elements, in the individual layers. Finally, the flipped carrier plate is passed to the stacking station 175, where the individual layers of completely processed powder are removed and placed on top of the stack of previously processed layers of powder to form the final product, for example, on a build platform. Suitable procedures for removing the individual layers from their respective carrier plates are described in the applicant's above-mentioned related application (U.S. Patent Application No. 18 / 074,298), as well as in another related provisional application by the applicant entitled "Method and Apparatus to Process and Bond Layers in an Additive Manufacturing System" filed on January 14, 2022 (U.S. Provisional Application No. 63 / 299,863).

[0015] Although FIG. 1a shows an embodiment of a system for performing a 3D printing process partially using a continuous substrate and partially using segments of a substrate mounted on a carrier frame, the specific steps performed using a continuous substrate and the steps performed using substrate segments mounted on a carrier frame can be modified. For example, in an alternative embodiment, the substrate segments with their respective layers of powder can be subjected to operations at a wetting agent drying station and a binder jetting and drying station before being mounted on the carrier frame. Alternatively, the cutting and segmenting stations can be located at a later point in the overall system. Furthermore, any number of processing steps can be performed on any substrate segment in any order.

[0016] FIG. 1b illustrates aspects and embodiments in which one or more sensing / monitoring modules 170 are utilized to control the operation of a continuous production system and a continuous substrate portion 105 providing higher throughput. Utilizing one or more sensing / monitoring modules 170 allows the data to be used to update, enhance, or refine the process, potentially increasing the efficiency of each stage of the process, increasing the automation of the system, and requiring fewer operators to oversee the entire process. In some embodiments, a subset of the sensing / monitoring modules 170 may be utilized, for example, based on which stage of the process experiences the most variation. The sensing / monitoring modules 170 may comprise, for example, one or more image acquisition devices, surface profilers, edge sensors, lubrication / wetting sensors, or other sensing / monitoring devices. In addition to the sensors described above, other sensors now known or later developed may also be incorporated into the continuous production system. A computer system (not shown) may analyze data from the various sensing / monitoring modules 170, determine whether the acquired data is within acceptable limits or below or above a predetermined threshold, and adjust one or more operating parameters of the automated system based on the analysis. In some embodiments, the computer system may orchestrate the operation of the system based on a configuration of rules, policies, or other logic that may be built into the system or input by a user through a user interface.

[0017] The right side of Fig. 1b shows a flow chart of steps of an AM manufacturing process performed on a continuous substrate, corresponding to the operations described above for the continuous substrate portion 105 of Fig. 1a. The left side of Fig. 1b shows a flow chart for data acquisition by various sensors 170 during various stages of the manufacturing process, the data acquisition occurring in association with the AM manufacturing process shown on the right side of Fig. 1b. The dashed arrowed lines indicate points in the AM manufacturing process where data is acquired and / or instructions are sent, according to aspects of the present disclosure.

[0018] In one aspect of the disclosure, a monitoring system, e.g., a vision system 172 associated with the powder deposition system 120, can determine one or more parameters of the thickness, surface profile, or topography of the dispensed powder level at one or more locations in real time. If the value of one or more parameters is determined by the computer system to be outside of a predetermined range or above / below a predetermined threshold, the powder deposition station / apparatus 120 may be adjusted accordingly. One example of a monitoring system that may be utilized for this purpose, e.g., a vision system 172, is described in co-pending application Ser. No. 17 / 842,701, entitled "Three-Dimensional ("3D") Printing Apparatus with Counter-Rotating Rollers." In one embodiment, analysis of the vision system data by the computer system can determine defects in the deposited powder or determine that one or more powder dispensers are not operating in an acceptable manner. In this situation, the computer system may communicate that information to a user via an interface / display and / or may modify the operation of functioning dispensers to compensate for the inadequacy. In another embodiment, if the computer system determines that the deposited powder is unavailable for further processing, the powder removal station 125 may be instructed to remove the entire deposited powder from the substrate. On the other hand, if the computer system determines that there are substantially no defects or that the value of one or more parameters is within an acceptable range or is an acceptable value, the powder removal station 125 may be instructed to create an isolated area of ​​powder, or a section of powder separated by a clean strip (an area from which powder has been removed), that is available for further processing.

[0019] In another aspect of the disclosure, a monitoring / sensing system, e.g., a clean strip / powder area determination system 174, which may be a vision system, can determine whether the powder removal action by the powder removal station 125 between adjacent sections of powder is sufficient. Sufficiency can be determined by the clean strip / powder area determination system 174 in a number of ways, for example, if it is possible to determine an edge of two adjacent powder sections sufficient to allow a cutting action to segment the two adjacent powder sections, if the area of ​​powder remaining on the clean strip, i.e., the "cleaned" section of the substrate, is below a predetermined threshold amount, or if a minimum area of ​​"cleaned" substrate is discernible between the two adjacent powder sections. In some embodiments, in addition to determining whether the powder removal action between adjacent sections of powder is sufficient, data from the same or a different vision system can be utilized to determine whether the two adjacent sections of powder produced are of acceptable form (e.g., not damaged by the powder removal process) and allow proceeding to the next process step without defects or errors or with defects or errors within an acceptable range.

[0020] In a further aspect of the present disclosure, a monitoring / sensing system comprising lubrication / wetting sensors 176 can enable the lubrication / wetting station 130 to control the wetting of the deposited powder layer. These sensors 176 enable an automated in-line monitor to detect quality issues related to the deposition / removal of wetting agents, such as wetting, drying, and steaming, in real time, thus minimizing the production of defective parts. In particular, according to an embodiment of the present disclosure, sensors 176 are provided that, together with intelligent software, can provide immediate feedback to the process control when a wetting quality issue (e.g., excessive wetting or insufficient wetting, both of which adversely affect the outcome of a subsequent compaction operation) is detected, thus minimizing the production of defective parts. An example of a monitoring system that can be utilized for this purpose is described in co-pending application Ser. No. 18 / 074,341, entitled "Wetness Sensor, Method and System for Sensing an Amount of a Wetting Agent," filed Dec. 2, 2022.

[0021] After passing through the lubrication / wetting station 130, the lubricated sections of deposited powder pass through a compaction station 135, which may comprise calender rollers where the powder is compacted. Then, at the (laser) cutting / segmentation station 140, the substrate is cut to separate each section of powder into an individual segment of substrate. In one embodiment, the substrate is segmented to separate at least two separate sections of powder. In one configuration, a monitoring / sensing system comprising an edge sensor 178 can be utilized to determine the position of the edge of the powder section as it exits the calender rollers, or the position of two adjacent edges of the powder as it exits the calender rollers. With this information, in combination with the speed at which the substrate is moving through the station, a computer system can be used to determine where to aim the laser, substantially at the center of the "clean strip" between the two edges of the powder that form the boundary of the two adjacent powder sections. To obtain a substantially straight line across the surface of the substrate that is substantially perpendicular to the edges of the substrate, in one embodiment, based on the speed relative to the moving substrate, the angle of the laser or other cutting device in the (laser) cutting / splitting station 140 can be adjusted to cut the substrate substantially in the middle of two adjacent edges of the powder as it traverses the substrate from one side to the other while it is moving. In another configuration, data indicative of the speed at which the substrate is moving can be utilized in combination with geometric information related to sections and / or "clean strips" of powder to determine where the substrate should be cut, and a computer system can be utilized to direct a cutting mechanism, such as a laser, to cut the substrate accordingly.

[0022] In one embodiment, prior to cutting, the sensor 178 may include a profilometer that may be used to determine the surface profile of the deposited powder, and in some instances to quantify its roughness or flatness and / or determine whether the quality of the surface is acceptable for continuing processing. In some configurations, if the surface roughness exceeds a predetermined threshold or is outside of an acceptable range, the computer system may command the substrate to be moved in a direction to interact with the compaction station 135 for further compaction. In other configurations, if the surface roughness exceeds a predetermined threshold or is outside of an acceptable range, the computer system may command that portion of the substrate be discarded and not subjected to further processing. In some embodiments, the discarding may include separating the compacted powder from the substrate and recovering and reconditioning (or reclaiming) the powder for reuse.

[0023] Once the powder sections are cut by the cutting / segmenting station 140, a profilometer 179 may also be utilized to check the quality of the powder prior to transferring the powder sections to the carrier frame. As also shown in FIG. 1b, if the results of any of the outputs of the various sensors 172, 174, 176, 178, and 179 are not acceptable, operation may be directed to discard or redirect the powder (step 177). In some embodiments, discarding may include recovering and reconditioning (or reclaiming) the powder for reuse.

[0024] FIG. 1c illustrates aspects and embodiments in which one or more sensing / monitoring modules 180 are utilized to control the operation of the carrier frame portion 110 providing a continuous production system and higher throughput. Similar to FIG. 1b, the utilization of one or more sensing / monitoring modules 180 in FIG. 1c allows data to be used to update, enhance, or refine the process, thereby potentially increasing the efficiency of each stage of the process, enhancing the automation of the production system, and allowing fewer operators to oversee the entire process. In some embodiments, a subset of the sensing / monitoring modules can be utilized, for example, based on which stage of the process the most variation occurs. A computer system (not shown) may analyze data from the sensing / monitoring modules and determine whether the acquired data is within acceptable limits or below or above a predetermined threshold, and may adjust one or more operating parameters of the automated system based on the analysis. In some embodiments, the computer system may orchestrate the operation of the system based on a configuration of rules, policies, or other logic that may be built into the system or input by a user through a user interface. The right side of FIG. 1c illustrates a flow chart of steps of the AM manufacturing process performed on the carrier frame, corresponding to the steps illustrated in FIG. 1a. On the left side of Fig. 1c is shown a flow chart for data acquisition by various sensors 180 during various stages of the manufacturing process, with data acquisition occurring in conjunction with the AM manufacturing process shown on the right side of Fig. 1c. The dashed arrowed lines indicate points in the AM manufacturing process where data is acquired and / or instructions are sent, according to embodiments of the present disclosure.

[0025] A monitoring / sensing system comprising wetting / drying sensors 182, 184, and 186 can enable control of the lubrication / wetting of the deposited powder layer by the lubrication / wetting and / or drying station 150, the binder jetting and drying station 155, and the material jetting and drying station 164. These sensors 182, 184, and 186 enable an automated in-line monitor to detect quality issues related to wetting, drying, and deposition / removal of lubrication / wetting agents such as steam, binder, material ink, etc., in real time, thus minimizing production of defective parts. In particular, according to an embodiment of the present disclosure, sensors are provided that, together with intelligent software, can provide immediate feedback to the process control when a wetting quality issue (e.g., excessive wetting or insufficient wetting, both of which adversely affect the outcome of a subsequent compaction operation) is detected, thus minimizing production of defective parts. An example of a monitoring system that can be utilized for this purpose is described in the above-mentioned co-pending application Ser. No. 18 / 074,341, entitled "Wetness Sensor, Method and System for Sensing an Amount of a Wetting Agent," filed on December 2, 2022.

[0026] In some embodiments, a quality determination sensor 188, such as an imaging device, may be incorporated to determine whether all unbound powder deposited on the substrate has been removed after the carrier frame has been flipped (step 160) and the laser (or other cutting device) has been operated (station 162). This may be determined by utilizing a computer system to compare the pattern in the image to an expected pattern at this particular stage of the process. In some embodiments, the expected pattern may be stored in a memory element of the computer system. If, after such a comparison, it is determined that some unbound powder still remains, the computer system may instruct the carrier frame to be flipped again until the remaining unbound powder is removed, redirect the laser (or other powder removal device) in the powder removal station 162 to perform additional powder removal based on the image data, or instruct one or more additional powder removal device(s), e.g., an air knife, to operate and remove the remaining unbound powder based on the amount and location of the remaining powder. An example of a powder removal system that may be utilized for this purpose is described in co-pending application Ser. No. 18 / 152,854, filed Jan. 11, 2023, entitled "Method and Apparatus for Powder Removal in an Additive Manufacturing System." In this regard, the surface profiler 187 may also be used to monitor the material (ink) jetting and drying station 164.

[0027] A quality determination sensor 188, such as an imaging device, may also interface with the computer system to verify the pattern created by the binder deposition to ensure that the pattern is expected and not an incorrect pattern. Based on whether the results are acceptable or not, as shown in FIG. 1c, the carrier frame may proceed to the next stage of processing, be stacked at the stacking station 165, redirected, or discarded accordingly, as shown by module 167. The stacking station 165 may also be monitored by a position sensor 189 to ensure that the layers are properly aligned.

[0028] The present disclosure also provides improved AM methods and systems, e.g., 3D printing systems, including an in-situ material reclamation system, where the material reclamation includes powder and / or liquid reclamation. The left side of FIG. 2 shows a flow chart of the steps of the AM process associated with a powder reclamation apparatus. FIG. 9 shows a flow chart of the AM process associated with a liquid reclamation apparatus. Specifically, FIG. 2 shows an example of a 3D printing system and process 200 that uses powder deposition on a moving substrate for a series of initial steps of the printing process, and then cuts the substrate into segments and mounts the segments, each with a layer of deposited powder, on individual carrier frames for the remaining steps of the printing process. More specifically, the right side of FIG. 2 shows a flow chart of a powder collection and reclamation process 210 that operates in conjunction with the 3D printing process 205 shown on the left side of FIG. 2. The dashed arrow line indicates a point in the 3D printing process 205 where a portion of the powder is collected for reclamation by the reclamation process 210 according to an embodiment of the present disclosure. It should be noted that these portions of powder collected in steps 220, 235, 250, and 280 may be a portion of the powder or all of the powder (e.g., an entire section of powder) present at the time of removal (including powder that has been treated with wetting agents, binders, or inks and is therefore no longer simply powder). In other words, any portion of the powder remaining at the time of collection, between 0% and 100%, may be collected in accordance with the present disclosure. Figures 4-6 show a more detailed flow chart of the 3D printing process steps of Figure 2, as well as specific points in the 3D printing process where powder (either clean or contaminated powder, depending on the stage of processing) is collected for reclamation.

[0029] The regeneration method and system 210 shown on the right side of FIG. 2 allows for the recovery, reconditioning and reuse of used powder, regardless of whether the powder is clean or contaminated. According to the present disclosure, as shown in FIG. 2, used clean powder can be collected first after powder deposition 215 followed by quality control rejection 220. Quality control can include, for example, height or thickness of the deposited powder, removal of excess deposited powder. In this case, a first portion of powder is removed, which is clean powder, i.e., powder that has not yet been "contaminated" by lubricants, wetting agents, binders, material inks, solvents, or other substances. The clean powder is stored in a first collection container, the clean powder container 225 of the classification system, as shown in FIG. 2. Additionally, during powder removal 230 to create sections of powder (segmenting the powder into adjacent layers of powder separated by clean portions of the substrate used for cutting later in the manufacturing process, as described below with respect to FIG. 6), the used clean powder, which may also be considered a first portion of the powder, is collected (step 235) and stored in clean powder container 225. Clean powder removal, collection, and reclamation are discussed further below with respect to FIG.

[0030] Still referring to FIG. 2, the used powder contaminated with wetting agent (step 240), referred to as the second portion of powder, can also be removed and collected after the compaction process 245 following quality control rejection 250, and is stored in a second collection container, the wetting agent contaminated powder container 255, as described below with reference to FIG. 5. Later in the printing process 205, after the laser cutting / segmenting step 260 (similar to steps 140, 150, and 155 in FIG. 1a), the wetting agent drying step 265, and the binder jetting and drying step 270, during the (laser) powder removal process 275 (similar to step 165 in FIG. 1a), a third portion of powder, which is the used unbound powder contaminated by binder, is removed and collected in step 280, and then stored in a third collection container, the binder contaminated powder container 285, for reclamation (step 290) and powder reuse (step 295). The printed layer on the substrate segment continues with material (ink) jetting and drying 277 and segment transfer and lamination 279. Removal, collection, and reclamation of binder-contaminated powder is discussed further below with respect to FIG.

[0031] Following powder collection and sorting at the various stages described above with reference to FIG. 2, the collected powder may be reconditioned by a powder regeneration system (step 290) and fed back for reuse in process step 205 shown on the left side of FIG. 2 (step 295). The regeneration of the powder in step 290 may be accomplished, for example, by sieving, drying, burnout, high temperature treatment, and spray drying processes. Furthermore, the type of regeneration depends on whether the powder is clean, contaminated with a wetting agent, or contaminated with a binder material, as described in more detail below. One or more of the regeneration steps may be performed in situ or at a location remote from the printing system.

[0032] In another embodiment, multiple 3D printing systems 300(1), 300(2), 300(3)...300(n) can be used in 3D printing manufacturing or other types of AM processes, as shown in Figure 3. Used powder is collected from each printing system (steps 310(1), 310(2), 310(3)...310(n), respectively), stored in centralized sorted powder storage bins for clean powder, wetting agent contaminated powder, and binder contaminated powder (225, 255, and 285, respectively), reconditioned or regenerated by a centralized powder reclamation system (step 290), and fed back to each printing system for reuse (step 295).

[0033] FIG. 4 illustrates a process 400 for the collection and reclamation of clean powder at an early point in the 3D printing process 205 shown in FIG. 2. In particular, as shown in FIG. 4, clean powder is collected after the powder deposition step 215. The thickness of the deposited powder is then checked in a quality control step (QC) 405. If, in step 410, the deposited powder layer fails this quality control check by not being within a predetermined thickness range, the entire powder layer is removed (step 415) and sent to the clean powder container 225. At this point, the process of FIG. 2 returns to the deposition of a new layer of powder (which can be drawn from the clean powder container 225 shown in FIGS. 2 and 4, if necessary).

[0034] As also shown in FIG. 4, clean powder is also collected in step 420, for example, during powder removal by vacuum from the nozzle configuration used to generate clean portions of the powder-free substrate. These clean portions of the substrate can be used to cut the substrate without disrupting the powder deposit on the substrate to create segments of the substrate, as described below. A suitable three-nozzle configuration for forming these clean sections is described in Applicant's related application, U.S. Patent Application No. 18 / 074,173, filed December 2, 2022, entitled "Apparatus and Method to Remove Powder with Flexible Scraper Blade and Adjustable Side Nozzles."

[0035] The clean powder from the clean powder container of FIG. 2 or FIG. 3 may be fed back directly for reuse. In some implementations, the clean powder is blended with virgin powder before being sent back for reuse. In other embodiments, the clean powder is reconditioned or regenerated by sieving, for example ultrasonic sieving, if powder agglomeration occurs during printing. In other embodiments, if there is significant moisture uptake in the powder during printing, the clean powder is first reconditioned by low temperature (e.g., <300° C.) drying using a convection or vacuum oven, followed by sieving to remove any large agglomerates that may have formed from drying. In yet other embodiments, if the powder reacts with components of air, such as carbon dioxide, to form carbonate by-products, the clean powder is reconditioned by high temperature (e.g., >300° C.) treatment to purify the powder by decomposing the carbonate by-products.

[0036] In other cases, there may be a significant increase in powder particle size and changes in powder particle shape caused by partial sintering from the high temperature treatment. In this case, the high temperature treated powder is reconditioned by grinding or milling to reduce the particle size. Grinding techniques to reduce particle size can include air classifier mills, pin mills, hammer mills, jet mills, and ball mills. After grinding, the high temperature treated powder is further reconditioned to restore the particle shape. For example, the high temperature treated and milled powder is further processed by spray drying to restore the spherical shape. One or more of these reconditioning methods can be applied sequentially or simultaneously, depending on the complexity of the reconditioning required.

[0037] FIG. 5 illustrates a process 500 for collecting and recovering powder contaminated with a wetting agent after wetting the powder at a wetting station (e.g., 130 in FIG. 1a) in process step 240 shown in FIG. 2. In this embodiment, as shown in FIG. 5, the powder is collected after a compaction step 245, e.g., a calendering step, which is performed after the powder is wetted to improve the calendering operation. Specifically, as described above with respect to FIG. 2 and in the applicant's related application entitled "Apparatus and Method to Provide Conditioning to a Deposited Powder" filed on December 2, 2022 (U.S. Patent Application No. 18 / 074,236), the powder is wetted to reduce undesirable adhesion of the powder to the calender rollers. The purpose of the calendering step 245 is to compact the powder and provide a compacted powder of uniform thickness. This allows for high packing densities (e.g., greater than 30%) that cannot be achieved with conventional AM systems. 5, the thickness of the compressed powder layer is checked in a second quality control (QC) step 510 after the powder layer passes through the calendering rollers. If the compacted powder layer does not meet specifications in this quality control inspection (step 515), for example, if the thickness of the compacted powder layer is not within a second predetermined range, the entire powder layer is removed and sent to wetting agent contaminated powder container 255. If step 515 determines that the thickness is within the predetermined range, the compacted powder layer is passed to the next step in the process shown in FIG.

[0038] In some implementations, the collected wetting agent contaminated powder is reconditioned or reclaimed in step 290 by sieving, e.g., ultrasonic sieving, blended with virgin powder, and then returned to the process shown in Figure 2 for reuse. In other embodiments, the wetting agent contaminated powder is reconditioned by first drying at low temperature (e.g., <300°C) to remove the wetting agent, and then sieving to remove any large agglomerates that may have formed from drying. One or more of these reconditioning methods can be applied sequentially or simultaneously, depending on the complexity of the reconditioning required.

[0039] FIG. 6 illustrates a process 600 for the collection and reclamation of binder-contaminated powder collected in step 610 at a later stage of the 3D printing process 210 shown in FIG. 2. In one embodiment, as shown in FIG. 6, the powder is collected in step 610 during the (laser) powder removal process 275 and stored in a binder-contaminated powder container 285. As also shown in FIG. 6, prior to the (laser) powder removal 275, the substrate with the deposited powder is cut in step 260 in the cleaned areas described above with respect to FIG. 2 and FIG. 4 to create individual substrate segments, each having a layer of compressed powder. After cutting, the substrate segments are transferred to a carrier frame in step 615. Next, in step 265, the powder layer on the individual substrate segments is dried to remove any residual wetting agent (applied to reduce powder adhesion to rollers in the calendering operation, as described above with respect to FIG. 5).

[0040] Each substrate segment is transferred to its own individual carrier frame in step 615 where it is secured in a locked position for further processing, such as, for example, binder application and drying. A suitable carrier frame system for this purpose is described in the applicant's related application (U.S. Patent Application Serial No. 18 / 074,298) referenced above. It should be noted that each individual carrier frame may have a unique identifier (e.g., an RFID tag, etc.) that associates the carrier frame with the particular individual layer mounted thereon.

[0041] As also shown in Figure 6, each individual carrier frame having a substrate segment with a layer attached thereto can then be inverted in step 620 to separate the layer from its corresponding substrate segment for stacking the layer on a stack of other layers to form a multi-layer product. This is part of the "segment transfer and stacking step" shown in Figure 2. This removal process of individual layers from substrate segments mounted on their respective carrier frames is also discussed in detail in the above-referenced related application by the same applicant (U.S. Patent Application Serial No. 18 / 074,298).

[0042] During this flipping process of the carrier frames in step 620, some of the powder (contaminated by binder) in the layer mounted on each carrier frame may fall off. Other binder-contaminated powder is removed in (laser) powder removal process 275 as discussed in the applicant's above-mentioned related applications (U.S. Patent Application No. 18 / 074,173 and U.S. Provisional Patent Application No. 63 / 299,776). All of this removed binder-contaminated powder is collected in binder-contaminated powder collection step 610 and deposited in binder-contaminated powder container 285 for powder reclamation, as shown in FIG. 2 and FIG. 6.

[0043] In some embodiments, the binder-contaminated powder is reconditioned by sieving, e.g., ultrasonic sieving, in step 290, blended with virgin powder, and then returned to the process shown in FIG. 2 for reuse. In other embodiments, the binder-contaminated powder is reconditioned by high-temperature (e.g., >300° C.) treatment to purify the powder by decomposing the binder. There may be a significant increase in powder particle size and changes in powder particle shape caused by partial sintering from this high-temperature treatment. In this case, the high-temperature treated powder is reconditioned by grinding or milling to reduce the particle size. Grinding techniques to reduce particle size can include air classifier mills, pin mills, hammer mills, jet mills, and ball mills. After grinding, the high-temperature treated powder is further reconditioned to restore the particle shape. For example, the high-temperature treated and ground powder can be further processed by spray drying to restore the spherical shape of the powder particles. One or more of these reconditioning methods can be applied sequentially or simultaneously, depending on the complexity of the reconditioning required.

[0044] FIG. 7 illustrates an example of a process 700 for collecting powder from various stages of the printing process described in FIG. 2 to generate powder that can be used in a subsequent printing process. In particular, as shown in FIG. 7, a regenerated powder mixture 710 is blended in step 712 for subsequent use. The regenerated powder mixture 710 includes one or more virgin powders 715, collected clean powder 720, regenerated clean powder 725, contaminated powder (1), 730, contaminated powder (2), 732, and a mixture of regenerated contaminated powders 735 and 740 (e.g., contaminated powder (1) may be a powder contaminated with a wetting agent, and contaminated powder (2) may be a powder contaminated with a binder). The virgin powder 715, i.e., a powder that has not yet been used in the printing process or has not undergone processing, may be added to the collected clean powder 720 (e.g., collected as described above with reference to FIG. 2) before undergoing regeneration, or may be added directly to the regenerated powder mixture 710. Although FIG. 7 shows only two types of contaminated powders 730 and 732, it will be apparent that any number of contaminated powders may be utilized and the form of regeneration performed will vary based on the process by which the contamination occurs.

[0045] There are numerous ways in which virgin powder 715, clean powder 720, regenerated clean powder 725, contaminated powders 730 and 732, and regenerated contaminated powders 735 and 740 can be combined to form the regenerated powder mixture 710. For example, referring to FIG. 7, B% may be 100% and 0% virgin, contaminated, or regenerated contaminated powders are used. Alternatively, C% and E% may both be 0% and only virgin and regenerated powders are combined to form the regenerated powder mixture. The values ​​of A%, B%, C%, D%, E% and F% may vary from 0 to 100%, with the percentages representing the percentages of the regenerated powder mixture. The percentages may be determined by the application in which the regenerated powder mixture is used. In some cases, when a particular powder purity is desired, it may be necessary to use, for example, a minimum of 20% to 30% virgin powder, 0% contaminated powder, and no more than 5% regenerated contaminated powder.

[0046] FIG. 8 shows an example of an alternative process 800 for collecting powder from various stages of the printing process described in FIG. 2 and FIG. 7 to generate powder that can be used in a subsequent printing process. In this embodiment, one or more portions of contaminated powder and regenerated contaminated powder varying in percentage from 0 to 100% are mixed or blended with classified clean powder 729 (which can be optionally premixed with virgin powder 715) in step 810, and then the entire mixture undergoes a regeneration process in step 820 to form a regenerated powder mixture 825, which can then be used in a subsequent process (step 830). Also, as shown in FIG. 8, a portion of the unused powder 715 can also be added to the regenerated powder mixture 825 before using the mixed powder in a subsequent process.

[0047] 7 and 8 show examples of the many ways in which virgin powder, clean powder, regenerated clean powder, contaminated powder, and regenerated contaminated powder can be combined to form a regenerated powder mixture, it will be apparent that the same methods are equally applicable to forming a regenerated liquid.

[0048] In some embodiments, an in-situ recycling system 900 may be included to allow recovery, reconditioning, and / or reuse of removed liquid, as shown in Figure 9. The left side of Figure 9 shows a flow chart of steps of an AM process using steps described above with reference to Figure 2 (e.g., steps 215-279). The right side of Figure 9 shows a flow chart of a wetting agent / liquid collection and reclamation process that operates in conjunction with the 3D printing process shown on the left side of Figure 9. The dashed arrow line indicates the point in the 3D printing process where the wetting agent / liquid is collected for reclamation, according to an embodiment of the present disclosure.

[0049] In one embodiment, the recovered liquid may be returned and used directly by the printing system. In some embodiments, the recovered liquid is collected and stored in a container before being fed back for reuse without reconditioning. In some embodiments, the recovered liquid is mixed with virgin liquid before being returned for reuse. During certain processes, different liquid mixtures may be generated and stored in classified liquid storage containers. To function properly, the liquid mixtures need to be purified or regenerated by additional processes. For example, wetting agents used for lubrication / wetting that become contaminated with powder need to be cleaned by an appropriate method, for example by filtration, to remove the powder contaminants before reuse. Similarly, liquids contaminated with binders or printing inks contaminated with other materials need to be purified before reuse.

[0050] 9, in process 910 during lubrication / wetting process 240, clean excess wetting agent can be collected and stored in a first collection container, clean wetting agent container 915. Excess vapor and / or condensed liquid can be collected from the wetting station in step 910, for example, with the aid of a hydrophilic material that provides a mechanism for transporting the condensed water to the wetting agent storage container 915 via one or more ports in the bottom of the wetting station.

[0051] Similarly, excess wetting agent may be collected in step 920 during the drying stage 265 of the printing process and stored in the same clean wetting agent container 915. During the binder jetting operation 270, excess liquid binder may be collected in step 925 from the binder jetting station, for example, using vacuum and / or differential pressure through a semi-permeable membrane, and stored in a second collection container, contaminated binder container 930. The liquid collected from the binder jetting may contain various resin binders, including monomers, polymers, and hardeners, solvents, and powder contaminants, and may be collected in the contaminated binder container 930. Additional solvent may be collected during a drying operation performed on the deposited binder in the same binder jetting station or a separate drying station, and stored in a fourth collection container, recovered solvent container 935.

[0052] 9, during the material (ink) jetting operation 277, excess ink can be collected in a process 940. In addition, used ink can be collected after quality control rejection (not shown). Solvent contained in the deposited ink can be collected during a drying operation performed on the deposited ink in the same material (ink) jetting station or a separate drying station and stored in a recovered solvent container 935, which can be the same or different container used for the solvent recovered from the binder jetting and drying operations. In some embodiments, a liquid removal operation can be performed on the deposited ink, for example, using a vacuum and / or differential pressure through a semi-permeable membrane to accelerate the drying process. The excess and used ink collected from the material (ink) jetting operation 277 and the liquid collected from the liquid removal operation 940 can be stored in separate containers or combined into a mixture, which is stored in a third collection container, the contaminated material ink container 945. The mixture can contain jetting materials such as metals, ceramics, and polymers, binders including monomers, polymers, and hardeners, solvents, and powder contaminants. Following storage of the various liquids in collection vessels 915 , 930 , 935 and 945 , the collected liquids may be regenerated in step 950 and then reused in step 955 .

[0053] There are numerous methods available for implementing the liquid reclamation process 900. For example, the process 900 can include filtration to remove solid materials, such as powders, from the liquid. In another example, distillation or evaporation can be applied to separate a liquid, such as a solvent, from solid particulates in a heterogeneous mixture. Distillation can also be applied to separate a liquid, such as a solvent, from a solute in a homogeneous mixture. Distillation can also be used to separate the solvent contained in the liquid after separation from the solids.

[0054] In this case, separation occurs due to differences in the physical properties of each component, especially the heat of vaporization. Solid-liquid based purification methods such as column chromatography, ion exchange chromatography, or other similar chromatographic methods can be utilized. This can include one or more additional steps such as centrifugation, or selective adsorption using additives such as high surface area carbon, molecular sieves, and other suitable adsorbent materials, where one particular component in the mixture has a higher affinity for the additive, and is then filtered to separate the components once absorbed by the additive. Alternatively, or additionally, liquid-liquid based purification methodologies may be used to separate the components of a mixture based on their solubility in two liquids, such as two or more solvents.

[0055] In another example, the mixture may be treated with some additional material, such as a compound or additive designed to induce crystallization or induce a chemical reaction that allows for the selective purification of one component in said mixture. Alternatively, or in addition, the mixture may be treated in other ways, such as pyrolysis or electrolysis, where one component undergoes some chemical transformation that allows for separation.

[0056] In some embodiments, a chemical composition analysis is performed on the recovered liquid to determine if reconditioning or regeneration is required to restore the composition of the liquid. In some implementations, the recovered liquid is regenerated by replenishing components consumed in the printing process. When multiple printing stations or systems are employed, the recovered liquid from each printing station or system is collected, mixed, and stored in a container, and the mixed liquid in the container is fed back for reuse by one or more of the multiple printing stations.

[0057] It should be noted that while the above description has been presented primarily with respect to removing and reclaiming powder or liquid on a substrate having a deposited layer in an additive manufacturing environment such as 3D printing, the methods and systems of the present disclosure are not limited to only such methods and systems, but may be used in any situation in which it is desirable to remove and reclaim powder and / or liquid from a substrate having an attached deposited layer.

[0058] It should also be noted that while specific examples of processing steps for a 3D printing operation have been shown and described, the order of processing steps can be changed as desired and / or additional processing steps can be added prior to the final stacking of layers. For example, the substrate can be segmented and layers on the substrate can be transferred to the carrier frame earlier in the overall process as desired. Also, a binder can be applied to layers on the segments of the substrate before the segments are mounted on the carrier frame. Also, the layers can be compressed after being mounted on the carrier frame, or as described above, an initial compression can be followed by further compression once the layers are mounted on the carrier frame.

[0059] Further features, characteristics and advantages of the present application are described by headings below.

[0060] Item 1: A method comprising: depositing powder on a substrate at a powder deposition station; removing a first portion of the powder to create a clean portion of the substrate between the portions of the deposited powder; moving the portions of the deposited powder remaining on the substrate to a wetting station where the powder is wetted with a wetting agent; passing the wetted portions of the deposited powder through a compression station to compress the powder; cutting the substrate at the clean portions to create substrate segments each including one of the portions of the deposited powder; transferring the substrate segments with the deposited powder mounted thereon to respective carrier frames; moving the substrate segments to a binder jetting station where a binder is deposited on the powder; and moving the carrier frame with the substrate segments with layers mounted thereon to a lamination station to laminate the layers individually onto one another to form a multi-layer product.

[0061] Item 2: The method of item 1, further comprising depositing the removed first portion of powder in a clean powder collection container.

[0062] Item 3: The method of items 1 or 2, further comprising inverting the carrier frame to separate the layer from the substrate segment.

[0063] Item 4: The method of any one of items 1 to 3, further comprising inverting the carrier frame to impact the loose / uncompressed powder away from the substrate.

[0064] Item 5: The method of any one of items 1 to 4, further comprising removing loose / uncompressed powder by a laser powder removal station after inverting the carrier frame.

[0065] Item 6: The method of any one of items 1 to 5, wherein the compression station includes a calender roller.

[0066] Item 7: The method of any one of items 1 to 6, further comprising determining, with a monitoring system coupled to the powder deposition station, one or more parameters of a thickness of the deposited powder, a level of the deposited powder, a surface profile of the deposited powder, or a topography.

[0067] Item 8: The method according to any one of items 1 to 7, wherein the surveillance system is a vision system.

[0068] Item 9: The method of any one of items 1 to 8, further comprising determining using a clean strip / powder area determining sensor whether powder removal between the portions of the deposited powder is sufficient to enable a cutting operation to segment the portion of the deposited powder into two adjacent powder sections.

[0069] Item 10: The method of any one of items 1 to 9, further comprising sensing a degree of wetting of the deposited powder by the wetting station using a wetting sensor, and providing feedback to control operation of the wetting station based on the measured degree of wetting of the deposited powder by the wetting station.

[0070] Item 11: The method of any one of items 1 to 10, further comprising using an edge sensor to determine a position of at least one edge of the powder section as the powder section leaves the compression station.

[0071] Item 12: The method of any one of items 1 to 11, wherein the edge sensor further includes a profilometer configured to determine a surface profile of the deposited powder by quantifying at least one of roughness, flatness, and / or quality of the surface profile of the deposited powder.

[0072] Item 13: The method according to any one of items 1 to 12, further comprising inspecting the quality of the powder using a profilometer after cutting the substrate with clean sections to create substrate segments and before transferring the portions of deposited powder to the carrier frame.

[0073] Item 14: A method according to any one of items 1 to 13, further comprising performing one or more printing processes or processing operations on the segment of the substrate, and drying the powder deposited on the segment of the substrate after the printing process or processing operation using a material jetting and drying station.

[0074] Item 15: The method according to any one of items 1 to 14, further comprising controlling the lubrication / wetting of the deposited powder layer by the wetting station, the binder application station, and the material jetting station and the drying station using a wetting / drying sensor.

[0075] Item 16: A method for 3D printing, comprising: generating at least two separate sections of powder on a substrate; segmenting the substrate to separate the at least two separate sections of powder; compressing the powder on the substrate segments; removing loose / uncompressed powder from the substrate segments; generating a printed / processed layer by performing one or more printing processes or processing operations on the substrate segments; and transferring the printed / processed layer from the substrate segments to a build platform.

[0076] Item 17: The method of item 16, wherein the individual sections of powder are lubricated / wetted prior to compression.

[0077] Item 18: The method of items 16 or 17, wherein the segmented substrate is transferred to a carrier frame before the binder is applied.

[0078] Item 19: The method of any one of items 16 to 18, wherein the carrier frame is inverted to affect loose / uncompressed powder that is separated from the substrate.

[0079] Item 20: The method of any one of items 16 to 19, further comprising depositing the removed loose / uncompressed powder in a contaminated powder collection container and reclaiming the powder from the contaminated powder collection container for reuse.

[0080] Item 21: A 3D printing system comprising: a powder deposition station configured to deposit powder on a continuous substrate; a powder removal station configured to generate at least two adjacent separate sections of powder on the continuous substrate separated by a powder-free clean strip of the continuous substrate; a cutting station configured to cut the continuous substrate at the clean strip of the continuous substrate to segment the continuous substrate into individual substrate segments and separate at least two separate sections of powder formed on adjacent segments of the individual substrate segments, respectively; a transfer station configured to transfer each of the individual substrate segments onto a corresponding individual carrier frame; an inversion station configured to invert the carrier frame such that the two separate sections of powder are suspended from the respective individual substrate segments on which they are deposited; and a stacking station configured to receive and stack the separate sections of powder from the respective carrier frames.

[0081] Item 22: The system of item 21, further comprising a compression station configured to compress individual sections of powder, and a laser powder removal station configured to remove loose / uncompressed powder from the substrate segments after transferring the substrate segments to the carrier frame.

[0082] Item 23: The system of items 21 or 22, further comprising depositing powder from the powder removal station into a first collection container, depositing loose / uncompacted powder from the laser powder removal station into a second collection container different from the first collection container, and regenerating powder from each of the first and second collection containers for reuse.

[0083] Although various embodiments have been described, the description is intended to be illustrative rather than limiting, and it is understood that many more embodiments are possible that are within the scope of the embodiments. Although many possible combinations of features are shown in the accompanying drawings and discussed in this detailed description, many other combinations of the disclosed features are possible. Any feature of any embodiment may be used in combination with or in place of any other feature or element in any other embodiment, unless specifically limited thereto. Thus, it will be understood that any of the features shown and / or discussed in this disclosure may be implemented together in any suitable combination.

[0084] While the above has described what is believed to be the best mode and / or other examples, it will be understood that various modifications can be made therein and that the subject matter disclosed herein can be embodied in a variety of forms and examples and that the teachings can be applied to numerous applications, only a few of which are described herein.

[0085] Unless otherwise indicated, all measurements, values, ratings, positions, dimensions, sizes, and other specifications set forth herein are approximate and not exact, and are intended to have a reasonable range consistent with the functions to which they relate and that which is customary in the art to which they pertain.

[0086] It will be understood that the terms and expressions used herein have the ordinary meanings given to such terms and expressions with respect to their corresponding respective fields of study and research, unless a specific meaning is otherwise set forth herein. Relative terms such as first and second may be used merely to distinguish one entity or action from another without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements may include other elements not expressly listed or inherent to such process, method, article, or apparatus, rather than including only those elements. An element preceded by "a" or "an" does not, without further constraints, preclude the presence of additional identical elements in the process, method, article, or apparatus that includes that element.

Claims

1. 1. A method comprising: depositing powder onto a substrate at a powder deposition station; removing a first portion of the powder to form a clean portion of the substrate between portions of deposited powder; moving the portion of the deposited powder remaining on the substrate to a wetting station where the powder is wetted with a wetting agent; passing the wetted portion of the deposited powder through a compression station to compress the powder; cutting the substrate at the clean portion to create substrate segments each including one of the portions of the deposited powder; transferring the substrate segment with the deposited powder thereon to a carrier frame; moving the substrate segment to a binder jetting station and applying a binder to the powder at the binder jetting station; and moving the carrier frame with the substrate segments with layers thereon to a stacking station to stack the layers individually on top of each other to form a multi-layer product.

2. 10. The method of claim 1, further comprising depositing the removed first portion of the powder in a clean powder collection container.

3. The method of claim 1 , further comprising inverting the carrier frame to separate the layer from the substrate segment.

4. The method of claim 1 , further comprising the step of inverting the carrier frame to affect loose / uncompressed powder away from the substrate.

5. 5. The method of claim 4, further comprising removing the loose / uncompressed powder with a laser powder removal station after inverting the carrier frame.

6. The method of claim 1 or 3, wherein the compression station comprises calender rollers.

7. 4. The method of claim 1 or 3, further comprising determining, with a monitoring system coupled to the powder deposition station, one or more parameters of a thickness of the deposited powder, a level of the deposited powder, a surface profile or a topography of the deposited powder.

8. The method of claim 7 , wherein the surveillance system is a vision system.

9. 4. The method of claim 1 or 3, further comprising determining using a clean strip / powder area determining sensor if powder removal between the portions of the deposited powder is sufficient to enable a cutting operation to segment the portions of the deposited powder into two adjacent powder sections.

10. 4. The method of claim 1 or 3, further comprising: sensing a degree of wetting of the deposited powder by the wetting station using a wetting sensor; and providing feedback to control operation of the wetting station based on the measured degree of wetting of the deposited powder by the wetting station.

11. 4. The method of claim 1 or 3, further comprising using an edge sensor to determine a position of at least one edge of the powder section as it leaves the compaction station.

12. 12. The method of claim 11 , wherein the edge sensor further comprises a profilometer configured to determine a surface profile of the deposited powder by quantifying at least one of a roughness, a flatness, and / or a quality of the surface profile of the deposited powder.

13. 4. The method of claim 1 or 3, further comprising inspecting a quality of the powder using a surface profilometer after cutting the substrate with the cleaned portion to create substrate segments and before transferring the deposited powder portion to the carrier frame.

14. 4. The method of claim 1 or 3, further comprising: performing one or more of a printing process or processing operation on the segment of the substrate; and drying the powder deposited on the segment of the substrate after the printing process or processing operation using a material jetting and drying station.

15. 15. The method of claim 14, further comprising controlling lubrication / wetting of the deposited powder layer by the wetting station, the binder application station, and the material jetting and drying stations using wetting / drying sensors.

16. 1. A method for 3D printing, comprising: creating at least two separate sections of powder on a substrate; segmenting the substrate to separate the at least two distinct sections of powder; compressing the powder on the segments of the substrate; removing loose / uncompressed powder from the segments of the substrate; - creating a printed / processed layer by performing one or more of the printing processes or processing operations on a segment of the substrate; and transferring the printed / processed layer from the segment of substrate to a build platform.

17. 17. The method of claim 16, wherein the discrete sections of powder are lubricated / wetted prior to compression.

18. The method of claim 16 , wherein the segmented substrate is transferred to a carrier frame before a binder is applied.

19. 20. The method of claim 18, further comprising inverting the carrier frame to act to move the loose / uncompressed powder away from the substrate.

20. 20. The method of claim 19, further comprising depositing the removed loose / uncompressed powder in a contaminated powder collection container and reclaiming the powder from the contaminated powder collection container for reuse.

21. 1. A three-dimensional printing system comprising: a powder deposition station configured to deposit powder onto a continuous substrate; a powder removal station configured to generate at least two adjacent distinct sections of powder on the continuous substrate, the sections being separated by a clean, powder-free strip; a cutting station configured to cut the continuous substrate at the clean strip of continuous substrate to segment the continuous substrate into individual substrate segments and to separate at least two distinct sections of powder respectively formed on adjacent segments of the individual substrate segments; a transfer station configured to transfer each individual substrate segment onto a corresponding individual carrier frame; an inversion station configured to invert the carrier frame such that two separate sections of powder are suspended from each respective substrate segment on which they are deposited; and a stacking station configured to receive and stack individual sections of powder from each carrier frame.

22. a compression station configured to compress the individual portions of the powder; 22. The apparatus of claim 21, further comprising a laser powder removal station configured to remove loose / uncompressed powder from the segments of the substrate after transferring the segments of the substrate to the carrier frame.

23. depositing powder from the powder removal station into a first collection container; depositing the loose / uncompacted powder from the laser powder removal station into a second collection container different from the first collection container; and reclaiming the powder from each of the first and second collection vessels for reuse.

Images