386 results about "Powder bed" patented technology

The invention belongs to the technical field of cable processing, and relates to a preparation method and application of a flexible superconducting coaxial cable outer conductor. The preparation method comprises the following steps: mixing Nb powder and Ti powder by adopting a vibrating ball mill to prepare NbTi composite powder; a substrate of laser powder bed melting equipment is preheated, the NbTi composite powder is spread on the substrate of the laser powder bed melting equipment, a melting powder layer is scanned through the laser powder bed melting technology, a three-dimensional communicated grid structure is formed through interlayer staggered scanning, finally, the NbTi net-shaped alloy pipe is placed in a strong acid solution to be soaked for a short time, redundant metal powder is removed, and the NbTi net-shaped alloy pipe is obtained. And finally, the preparation of the flexible superconducting coaxial cable outer conductor for the quantum computer is realized.

The invention discloses a TiAl alloy electron beam selective melting and shot peening strengthening in-situ compounding manufacturing method and device, and relates to the technical field of additive manufacturing. The method comprises the following steps: establishing a three-dimensional digital model of a to-be-printed part, and performing slicing and layering to obtain layered scanning data; under the vacuum condition, TiAl alloy powder is spread on the preheated base plate according to the set thickness, and a powder bed is formed; according to the layered scanning data, scanning and melting the powder bed through a focused electron beam, completing single-layer scanning and melting, completing scanning and melting layer by layer until the part is printed and cooled, and recovering unmelted TiAl alloy powder; and under the vacuum condition, the surface of the printed part is scanned and heated through a defocusing electron beam, TiAl alloy powder is adopted as shot blasting powder, the surface of the heated part is subjected to microparticle shot blasting strengthening treatment, after the treatment is finished, cooling is conducted, scattered shot blasting powder is recycled, and the finished TiAl alloy part is obtained. By means of the collaborative process design of electron beam selective melting and in-situ high-temperature microparticle shot blasting and device integration, the problems that in TiAl alloy additive manufacturing, cracking is prone to occurring, and the strengthening effect is poor are solved.

A method of three-dimensional printing can include iteratively applying a polymer build material as individual layers to a powder bed, where the polymer build material includes from about 80 wt % to 100 wt % polymeric particles, and based on a three-dimensional object model, selectively applying a coalescing agent onto individual layers of the polymer build material. The coalescing agent can include an aqueous liquid vehicle and a coalescing solvent that depresses a melting point of the polymeric particles. The method can include exposing the powder bed to heat to selectively coalesce portions of individual layers of the polymer build material in contact with the coalescing solvent. The heat may not be sufficient to coalesce the polymer build material that is not in contact with the coalescing solvent and may be sufficient to fuse the polymeric particles in contact with the coalescing solvent together to form a three-dimensional object.

Provided is an ultrafast laser shock forging assisted laser powder bed fusion (LPBF) method with an ultrafast laser to allow on-line control of a stress field for an additive-manufactured component. Technical points of the present disclosure: During a LPBF-based additive manufacturing process, ultra-high-pressure shock waves induced byan ultrafast laser are allowed to forge a molten layer on-line, and a stress field distribution of a molten layer can be accurately controlled layer by layer, so as to reduce a residual stress level of an additive-manufactured component and improve the mechanical properties of an additive-manufactured component, thereby allowing the high-performance LPBF-based additive manufacturing. The present disclosure has the following advantages: Due to the layer-by-layer shock forging mode, the method can control a stress field with a high accuracy and a better effect, will not cause secondary pollution or destruction, and exhibits excellent technical applicability.

The present disclosure relates to a fabrication and evaluation process for testing new metallic alloy chemistries and compositions for laser powder bed fusion (L-PBF). The new methodology is efficient and effective for new compositions with a minimal investment of generating large quantities of powder feedstock for required in conventional AM processing. The method allows for subsurface melting of the new alloy composition by varying the depth of penetration by a control of the input power level, power deposition rate, and rastering scan strategy. Post-mortem analysis of the subsurface microstructure permits an analysis of the durability and suitability of the new metallic alloy for this manufacturing mode. The method utilizes available infrastructure, technology, and characterization techniques.

The invention discloses a composite powder spreading device for large-size multi-electron-beam selective melting forming. The composite powder spreading device comprises a powder falling device, a powder falling opening partition plate, a composite scraper mounting frame, a rear rolling shaft, a powder collecting device and a scraper blade. The upper end of the powder falling device is connected with the powder conveying channel; the powder collecting device moves to the position below the powder falling device when receiving the powder, leaves the position below the powder falling device after receiving the powder, and moves along the forming area to spread the powder; the powder falling opening partition plate is opened when the powder collecting device receives the powder and is closed after the powder is received; a rear rolling shaft and a scraper blade are mounted on the composite scraper mounting frame; the scraper blade and the rear rolling shaft synchronously move along with the powder collecting device, the scraper blade is used for scraping the powder in the powder laying process, and the rear rolling shaft is used for compacting the scraped powder. According to the method, the powder spreading state of the powder bed can be improved, the powder spreading uniformity of the large-amplitude powder bed is improved, pores among powder are reduced, the stability of the electron beam selective melting process is optimized, and the printing success rate is increased.

The embodiment of the invention discloses a preheating process parameter optimization method for inhibiting powder blowing of an electron beam powder bed, relates to the technical field of additive manufacturing, and aims to solve the problems that the development of preheating process parameters of the electron beam powder bed is difficult and the period is long. The preheating process parameter optimization method for suppressing powder blowing of the electron beam powder bed comprises the following steps: acquiring a preheating current gradient growth mode and bottom plate preheating process parameters adopted by a target process; determining target powder bed preheating key parameters based on the preheating current gradient growth mode and the bottom plate preheating process parameters; and the target powder bed preheating key parameters have no powder blowing phenomenon in the printing process. By means of the technological parameter development process, preheating technological parameters can be rapidly obtained, and the development progress of melting forming of the electron beam powder bed is shortened.

The invention discloses an additive manufacturing powder bed preheating system and method based on hot air-partition radiation synergy. The additive manufacturing powder bed preheating system comprises a preheating outer box, a powder bed, a hot air circulating system, a partition radiation heating system and a layering synergy controller. The method has the beneficial effects that an upper-layer steady-state optimization and lower-layer dynamic compensation framework is adopted, wherein the upper layer aims at energy efficiency and temperature uniformity, and the temperature and the air speed of a hot air inlet are optimized; and the lower layer is based on real-time temperature feedback, the partition radiation power is adjusted through a feedback + feedforward decoupling algorithm, local temperature disturbance is compensated, hot air rapidity and partition radiation accuracy are fused, the problems of response lag, space coupling and laser preheating cooperation deficiency are solved, rapid, uniform and dynamic regulation and control of the temperature field of the powder bed are achieved, the additive manufacturing quality is improved, and the production efficiency is improved. The method is suitable for high-precision manufacturing of various high polymer materials.

Systems, methods, and programs for detecting and removing defects on a part during laser powder bed fusion manufacturing are described. A sensor may detect defects on the part during manufacturing of the part. A controller may obtain the sensor data and determine the defect and control a short-pulse laser to remove the defect. Furthermore, processes of manufacture and material properties of the part may be evaluated to determine a likelihood of a defect and the short-pulse laser may be operated to reduce the likelihood of the defect. Furthermore, the short-pulse laser may be operated to reduce stress in layers of the part.

The invention belongs to the technical field of titanium alloy additive manufacturing, and particularly relates to an electron beam additive manufacturing method for oxygen-enriched titanium alloy. According to the method, circulating titanium alloy coarse powder with the oxygen content being 0.25 wt.%-0.30 wt.% is adopted, the circulating titanium alloy coarse powder is dried and then subjected to printing forming, and a powder layer is obtained; according to the method, electron beam powder bed cladding is conducted on a powder layer under the environment that the vacuum degree is 10 <-3 > Pa to 10 <-5 > Pa, a BCC phase is reserved by means of a steady-state thermal field formed by electron beam powder bed cladding at a preheated substrate at the temperature of 700 DEG C to 800 DEG C, in the deformation process, transformation from BCC to HCP and transformation from HCP to FCC are induced by stress, and the high-toughness oxygen-enriched titanium alloy is obtained; the excellent performance matching of the tensile strength of 1220 MPa and the elongation percentage of 14.5% is realized, and meanwhile, the uniform elongation percentage of 8.1% is kept.

The invention discloses a laser powder bed molten high-strength, high-plasticity and high-work-hardening titanium alloy and a preparation method and application thereof.The preparation method comprises the steps that two kinds of titanium alloy powder with different Mo equivalents are mixed according to a certain mass ratio to form mixed powder, and the mixed powder is put into laser powder bed melting equipment; the titanium alloy is finally obtained through layer-by-layer forming by laser powder bed melting equipment according to a slicing path and process parameters of a three-dimensional model, the microstructure of the prepared titanium alloy comprises hexagonal martensite alpha 'and orthorhombic martensite alpha', and in a preferable scheme, under the condition that heat treatment is not needed, the yield strength of the titanium alloy is larger than or equal to 950 MPa, the tensile strength is larger than or equal to 1250 MPa, and the tensile strength is larger than or equal to 1250 MPa. The alloy has the advantages of high strength, high plasticity and excellent work hardening capacity, can meet the requirements of forming and high mechanical properties of titanium alloy components in complex shapes, and is especially suitable for the fields of aerospace, automobiles, weapon armors, ships, oceans and the like, and the ductility is greater than or equal to 14%, and the work hardening capacity is greater than or equal to 250 MPa.

A molten pool image processing method in the laser powder bed melting process comprises the steps that the center of a nominal molten pool is positioned, a region of interest is extracted, an optimal gray threshold value is calculated through a self-adaptive threshold value algorithm, binary processing is conducted on a gray image, and a binary molten pool image is obtained; performing edge detection on the binary molten pool image to obtain an edge image, constructing an edge point polar coordinate sequence, and calculating a polar angle difference matrix and a polar radius difference matrix; calculating the number of contours in the edge image, and judging whether the edge image has splashing points or not; calculating a polar angle difference value of adjacent edge points, and judging whether the contour of the molten pool is closed; on the premise of ensuring that the contour of the molten pool is closed, based on the shape symmetry assumption of the molten pool, the distance between symmetric points of the molten pool is calculated, basic geometrical characteristics of the molten pool are extracted, and physical values of the basic geometrical characteristics of the molten pool are calculated. Based on the gray level and spatial distribution difference of the molten pool and the background noise, the challenge of tracking the morphology of the molten pool under any processing condition in the actual production process can be relieved.

The invention discloses an electron beam additive manufacturing method for an integrated copper-chromium contact-conducting rod assembly, and belongs to the technical field of copper-chromium contact manufacturing. The electron beam additive manufacturing method comprises the steps that S1, a special powder system is designed and prepared, specifically, contact area powder and conducting rod area powder are prepared and subjected to drying treatment; s2, digital modeling and support design: establishing an integrated copper-chromium contact-conducting rod assembly model by using three-dimensional software and slicing; S3, fusing and integrally forming by using an electron beam powder bed: printing an integrated copper-chromium contact-conducting rod assembly in a vacuum chamber of the electron beam powder bed, and S4, a printing post-treatment process is carried out, specifically, returning treatment, hot isostatic pressing treatment and machining treatment are carried out on the integrated copper-chromium contact-conducting rod assembly printed piece. According to the printing post-treatment process, the residual stress of the integrated copper-chromium contact-conducting rod assembly can be effectively eliminated through the printing post-treatment process; and the problems of macroscopic cracks and part warping caused by high residual thermal stress can be effectively avoided.

The invention belongs to the technical field of 3D printing, and particularly relates to a continuous pulse mixed type patterning laser powder bed light path system and method.Laser powder is preheated to be close to a melting point but not molten through set continuous-period light emitting, the preheated laser powder is completely molten through pulse-period light emitting, and in other words, the continuous pulse mixed type patterning laser powder bed light path system and method are obtained; continuous light is only used for preheating powder for a short time, so that the powder is close to a melting point but not molten; then peak energy is rapidly provided through microsecond pulsed light, powder melting is completed instantly, in this way, the effective heating time is shortened, the heat radiation range of heating is controlled, the heating time of a system is far shorter than the heating time of traditional continuous light, melting and solidification are completed when heat is not diffused out of a preset pattern in time, and the production efficiency is greatly improved. Therefore, the fusion area is limited within the pattern range, the subsequent part forming precision is improved, and laser loss caused by too high peak power due to short time is reduced through pulse light emitting and continuous light emitting.

The invention discloses an electron beam powder bed lap joint process parameter development method and device, and belongs to the technical field of electron beam selective melting. Comprising the following steps: performing partition segmentation on a forming section printed by an electron beam powder bed to obtain a plurality of adjacent partitions, and determining key process parameter types of lap joint areas between the adjacent partitions; wherein the key process parameter type comprises a lap joint distance and a random offset distance; based on existing typical line length filling parameters, designing an orthogonal test of a lap joint distance and a random offset distance, printing a test block, carrying out visual inspection and metallographic dissection, and determining a candidate parameter interval by taking no hole defect as a target; and obtaining candidate parameter intervals corresponding to the plurality of different typical line lengths, and determining the optimal value of the key process parameter type in the plurality of different candidate parameter intervals. The metallurgical quality effect of the lap joint area in the filling process can be guaranteed, and the metallurgical quality and consistency of the filling area can be improved.

Provided is an ultrafast laser shock forging assisted laser powder bed fusion (LPBF) method capable of inhibiting formation of thermal cracks in a high-strength aluminum alloy. Technical points of the present disclosure: During a LPBF process of an aluminum alloy, a molten layer is subjected to shock forging with a mechanical effect of ultra-high-pressure shock waves induced by an ultrafast laser to reduce a stress level of the molten layer, and a stress level is controlled layer by layer to eliminate the local stress concentration, thereby inhibiting the formation of thermal cracks. Advantages of the present disclosure: During a LPBF-based additive manufacturing process, a stress field is controlled to inhibit the formation of thermal cracks, and there is no need to add an alloying element or adopt a post-treatment, resulting in a simple and reliable process. A thermal crack density is accurately and efficiently controlled layer by layer.

The utility model discloses a powder spreading mechanism based on a 3D printer and a 3D printing device, and the powder spreading mechanism comprises a translation cross beam frame capable of performing translation motion; the powder spreading roller body is arranged on the translation cross beam frame in a switching assembly manner; and two end parts of the driving rope body are positioned, and the driving rope body is assembled on the powder spreading roller body in a winding manner. According to the mechanism and the device, the powder spreading roller body can be effectively driven to translate corresponding to the powder spreading bed through the translating cross beam frame, and meanwhile, smooth low-vibration powder spreading can be effectively realized by utilizing the roller body transmission part based on the driving rope body under the friction driving action of the rope wheel, so that the stability of the flattening function of the powder bed is remarkably enhanced, and the functional practicability is improved.

The present invention relates to a method for powder-bed fusion additive manufacturing of a radiofrequency device, comprising a depowdering step, during which the powder residue is discharged through a through-hole (10, 20) made in the manufacturing support (S) and / or in a wall of the radiofrequency device (1) adjacent to the manufacturing support (S) without the manufactured radiofrequency device (1) having to be separated from the manufacturing support (S) during the step of discharging the powder residue. The invention also relates to a manufacturing support comprising at least one through-hole (10) allowing a powder residue to be discharged during a depowdering step. (Fig. 2)

The invention belongs to the technical field of additive manufacturing, and particularly relates to a powder bed sintering method for PAEKs and a composite material thereof, which is particularly suitable for inhibiting buckling deformation caused by crystallization shrinkage in a low-temperature sintering process of PEEK, PEKK and a composite material thereof. Comprising the following steps that the size of a base is designed for a to-be-sintered sample piece, the x-y size of the base is larger than the projected area of the sample piece, and the thickness is smaller than 1 mm; the base is divided into n layers according to the thickness, and n is larger than or equal to 3 and smaller than or equal to 6; pAEKs and a composite material thereof are subjected to powder spreading and preheating in powder bed sintering equipment, and preparation work before sintering is completed; sintering the base structure layer by layer to form a constraint base with certain elasticity; the sample piece is sintered on the base, shrinkage deformation of the material is restrained through mechanical constraint of the base on the sample piece, and the sample piece sintering operation is completed.

A powder bed container (20) and an additive manufacturing apparatus (1) and method utilizing the powder bed container (20) are provided. The powder bed container (20) comprises a container body (200), a guide part (201) and a pushing and pressing part (202), the guide part (201) is installed in the container body (200) and makes contact with a base table (203) used for forming a powder bed (102) above the guide part (201), and the guide part (201) is used for guiding the base table (203) to move; the pushing and pressing part (202) is used for pushing the supporting component (3) in the movement direction and driving the base table (203) to move synchronously by utilizing the supporting component (3); wherein the support member (3) is formed synchronously when the target member (2) is formed. According to the application, the base station (203) is designed to move unidirectionally along the set direction, so that the overall size of the guide part (201) is designed to be close to the actual stroke, thereby reducing the equipment size and reducing the occupied space.

Methods of three-dimensional printing can include iteratively applying a polymer build material as individual layers to a powder bed, where the polymer build material includes from about 80 wt % to 100 wt % polymer build particles, and based on a three-dimensional object model, selectively applying a binder agent including an aqueous liquid vehicle and polymer binder particles onto the individual layers of the polymer build material. The polymer binder particles have or are capable of having a melting temperature lower than a melting temperature of the polymer build particles. The methods can include exposing the powder bed to heat at a temperature less than a melting point of the polymer build particles but greater than a melting temperature of the polymer binder particles. The heat causes the polymer binder particles to melt to adhere the polymer build particles together to form a three-dimensional object.

The invention discloses a laser powder bed sheet pattern distortion real-time correction system and method based on a phase type light valve, and relates to the technical field of metal additive manufacturing. The system comprises a polarization laser, a beam expanding and collimating unit, a reflecting mirror, a phase-type spatial light modulator, a reflecting mirror, a relay optical system, a galvanometer / field lens system, a movable spectroscope, a reference plane mirror and a forming cylinder. A double-loop correction system with a position sensitive detector as an absolute reference and a wavefront sensor as direct feedback is constructed, information of the position sensitive detector and the wavefront sensor is unified in a phase domain through a frequency domain fusion algorithm, and a comprehensive compensation phase diagram capable of completing pattern generation and distortion correction at the same time is generated. And loading to a phase type light valve to carry out high-power laser patterning modulation, and melting metal powder of a powder bed.

A method of determining instructions to be executed by a powder bed fusion apparatus, in which an object is built in a layer-by-layer manner by selectively irradiating each of a plurality of successively formed powder layers with an energy beam. The method comprises determining, for at least one of the powder layers, a scan path for the energy beam to scan to melt powder of the powder layer, the scan path including bulk irradiation locations, wherein, for each bulk irradiation location, powder is melted by the energy beam to form, together with powder melted by irradiation of previous powder layers, a thickness of consolidated material from the bulk irradiation location to a surface of the object above a bulk threshold, and non- bulk irradiation locations, wherein, for each non-bulk irradiation location, powder is melted to form a thickness of consolidated material from the non-bulk irradiation location to a surface of the object less than the bulk threshold. The method comprises allocating a bulk value for an exposure parameter to the bulk irradiation locations, and determining a non-bulk value for the exposure parameter for each non-bulk irradiation location dependent on, at least in part, the thickness of the consolidated material from the non-bulk irradiation location.

This disclosure is directed to a method for modeling additive manufacturing of a part, including a number of steps. The steps include constructing a model for estimating output of a simulated additive manufacturing process, followed by entering process operating parameters for an additive manufacturing system into the model to produce an output. The output is compared to acceptance criteria to determine whether the output is acceptable or unacceptable. Next regions of operating parameters that support production of the part with acceptable quality characteristics are determined based upon the output. Regions of operating parameters that support production of the part with acceptable quality characteristics are added to a process map for additive manufacturing the part. The steps are repeated for different operating parameters until the process map is complete.

This invention provides a three-dimensional molding apparatus and method that improve molding accuracy in three-dimensional molding, which involves repeatedly melting and solidifying powder and then cutting it to form a three-dimensional object. [Solution] In a powder bed type three-dimensional molding apparatus, a laser is irradiated onto metal powder to melt and solidify the powder, forming thin layers, and these thin layers are stacked to create a three-dimensional object. At this time, the molding accuracy of the object is improved by cutting off the formed layers after each predetermined layer has been formed, such as 10 layers. The cutting data that defines the cutting shape uses a shape S3 obtained by reflecting the displacement d1 between the desired shape S1 and the shape S2 whose deformation has been predicted by simulation onto shape S1. Alternatively, the deformation of shape S3 may be further predicted to obtain a displacement d2 between it and shape S1, and a shape S5 that reflects this displacement may be used as the cutting data.

The present application relates to the technical field of 3D printing, and provides a long-width 3D printer and a printing method, which comprise a printing cabin, a powder bed, a compartment dividing mechanism, a powder laying device, a wind field circulation system and a powder bed divided into a first printing area and a second printing area along the length direction of the printing cavity, wherein the compartment dividing mechanism comprises a compartment main plate, and a scraper avoiding space exists between the compartment main plate and the powder bed; the wind field circulation system comprises an air inlet cover assembly, an air outlet cover assembly, an air inlet double valve mechanism and an air outlet double valve mechanism; the powder laying device comprises a scraper assembly movably arranged in the printing cabin and capable of passing through the scraper avoiding space, and a scraper driving mechanism for driving the scraper assembly to perform a powder laying action on the powder bed.

A scanning path planning method for a metal laser powder bed fusion forming process comprises the steps that 1, a TPMS lattice model is built through an implicit function equation, slicing is conducted through an implicit slicing method, and a two-dimensional contour is obtained; 2, generating a multi-stage initial contour line path through contour surface constants of the uniform change implicit function equation; 3, calculating the distance between the adjacent initial isoline paths, and identifying an area with the distance exceeding a preset tolerance as an unqualified area and the rest as a qualified area; 4, retaining an initial isoline path in the qualified area, and generating a grid filling path in the unqualified area to obtain a mixed path set; 5, inputting a mixed path set, and on the premise of not changing geometric coordinates of each path section, carrying out connection sequence optimization on all the path sections to form a continuous scanning track; and 6, converting the formed continuous scanning track into a file format which can be executed by laser powder bed melting equipment. According to the method, the powder adhesion and deformation risks are remarkably reduced, and the SLM forming precision and efficiency are improved.

A long-format 3D printer and a printing method. The long-format 3D printer comprises: a printing chamber (1); a powder bed (2), in the direction of length of a printing cavity (11), the powder bed (2) being divided into a first printing zone (21) and a second printing zone (22) connected to each other; a partition mechanism (3), the partition mechanism (3) comprising a partition main plate (32), a scraper clearance space (53) being provided between the partition main plate (32) and the powder bed (2); a wind field circulation system (4), the wind field circulation system (4) comprising an air intake cover assembly (41), an air output cover assembly (42), an air intake double-valve mechanism (43) and an air output double-valve mechanism (44); and a powder spreading device (5), the powder spreading device (5) comprising a scraper assembly (51), which is movably arranged in the printing chamber (1) and can pass through the scraper clearance space (53), and a scraper driving mechanism (52) for driving the scraper assembly (51) to perform a powder spreading action on the powder bed (2).

The present disclosure provides systems and methods for the formation of three-dimensional objects. A method for forming a three-dimensional object may comprise alternately and sequentially applying a stream comprising a binding substance to an area of a layer of powder material in a powder bed, and generating at least one perimeter of the three-dimensional object in the area. The stream may be applied in accordance with a model design of the three-dimensional object. The at least one perimeter may generated in accordance with the model design.

A method is provided of simulating additive manufacturing in which powder is used to additively manufacture an object The method comprises using a particle model to model application of powder, for example in form of a deposited powder bed, over a substrate layer during the additive manufacture, initiating a simulation model of the additive manufacturing, wherein the simulation model uses computational fluid dynamics to simulate 3D volumetric fields at respective time instances during the additive manufacturing, and executing the simulation model to obtain at least a 3D phase field and a 3D temperature field at respective time instances during manufacture of a first line structure on the substrate layer to simulate temperature evolution and phase changes during the manufacture of the first line structure.