218 results about "4d printing" patented technology

An appliance comprises a passive component and an active force generating component, in which the active force generating component is configured to react to a stimulus and generate tooth movement forces. In some embodiments, the passive component is configured to deflect when placed on one or more teeth and generate tooth movement forces, which are combined with tooth movement forces of the force generating component. In some embodiments, the passive component comprises a polymer which is less reactive to the stimulus than the force generating component. The force generating component can be configured to increase force to one or more teeth at an appropriate time.

The invention provides a laser cladding 3D / 4D printing system and method, and the method comprises the following steps: S1, constructing a three-dimensional model of a to-be-printed piece, slicing the three-dimensional model, and generating a two-dimensional interface diagram of each layer of printing; s2, the additive manufacturing material of the current layer is melted through first laser to form a cladding layer; s3, carrying out micro-shaping on the surface of the cladding layer by using second laser, firstly carrying out micro-shaping on rough and hole defect areas on the surface of the cladding layer, and then carrying out point heat source irradiation on the surface of the cladding layer to eliminate residual stress of the cladding layer; and S4, the steps S2-S3 are repeated, the additive manufacturing process of each layer is completed, and a printed piece is obtained. According to the method, ultrafast laser shaping is carried out on the cladding layer in the laser 3D / 4D printing process, so that the problems of residual stress, interface-surface holes, uneven roughness and powder agglomeration and accumulation of the cladding layer of a laser 3D / 4D printing workpiece are solved, and the quality of the laser 3D / 4D printing workpiece is improved.

A three-dimensional transformable structure containing a set of individual elementary components, so-called IECs, forming a single-piece assembly. An IEC includes an active or inert material and at least one portion of the set of IECs includes at least three connecting means. Each connecting means of a considered IEC is arranged to cooperate with at least one connecting means of an IEC adjacent to the considered IEC to connect the considered IEC to the adjacent IEC. For the at least one portion of the set of IECs, at least one of the connecting means of a given IEC is located on a side opposite to at least another one of the connecting means of the considered IEC. At least one portion of the set of IECs includes so-called “active” IECs spatially arranged in the transformable structure so that at least one property of the transformable structure is modified in response to the application of at least one stimulus.

The invention relates to a 4D printing hydrogel material and a preparation method and application thereof, and belongs to the technical field of hydrogel materials.The preparation method of the 4D printing hydrogel material comprises the steps that S1, N-isopropylacrylamide is subjected to a prepolymerization reaction under the action of a photoinitiator, and a prepolymer is obtained; s2, the prepolymer, [2-(methylacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide and a cross-linking agent are mixed, and printing slurry is obtained; s3, carrying out 3D photocuring printing by adopting the printing slurry to obtain a hydrogel matrix with a porous structure; and S4, soaking the hydrogel matrix in a lithium salt solution to obtain the 4D printing hydrogel material. The 4D printing hydrogel material provided by the invention can generate a volume swelling phenomenon in a moisture absorption process, has rapid moisture absorption dynamics and ultrahigh moisture absorption capacity, and has excellent moisture storage and water collection capacities.

The invention discloses a reversible metal 4D printing method based on hydrogel reversible deformation and a metal part, and belongs to the field of metal additive manufacturing. The method comprises the following steps: firstly, constructing a three-dimensional model comprising a hydrogel driving layer and a metal blank layer; respectively preparing hydrogel light-cured ink and metal or precursor slurry thereof; printing the two layers of materials sequentially or alternately by adopting a photocuring printer to obtain a composite green body; the hydrogel layer is dehydrated and shrunk through drying, the component is driven to generate preset shape deformation, the hydrogel layer absorbs water and expands through soaking, and reversible recovery of the shape of the component is achieved; and degreasing, selective reduction and sintering heat treatment are conducted on the component, and the compact final metal component is obtained. According to the invention, the independent hydrogel layer is used as a deformation driver, the dependence on the intrinsic phase change characteristic of a metal material is avoided, the material universality is extremely high, the method can be widely applied to 4D printing of various materials including refractory metal and high-reflection metal, and reversible control of shape change is realized.

A shape memory ceramic is provided. The shape memory ceramic includes a first portion and a second portion. The first portion and the second portion of the shape memory ceramic are bonded, and the shape memory ceramic is an elastomer-derived ceramic comprising silicon oxycarbide. The first portion of the shape memory ceramic is treated with ultraviolet ozone, and the second portion of the shape memory ceramic is not treated with ultraviolet ozone. The invention also provides a manufacturing method and a 4D printing method of the shape memory ceramic.

The invention provides a 4D printing esophageal stent and a preparation method thereof. The esophageal stent comprises a stent main body and a drug-loaded fiber membrane with a core-shell structure, the stent main body is a tubular stent composed of a bionic water lily hollow structure; the diameters of the head end and the tail end of the support body are larger than the diameter of the middle section, and barb structures are arranged on the outer surfaces of the head end and the tail end. The stent main body is a biodegradable shape memory polymer; the drug-loaded fibrous membrane is positioned on the outer surface of the middle section of the stent main body, and the drug-loaded fibrous membrane contains drugs. The 4D printing esophageal stent provided by the invention has excellent compressive bearing capacity and anti-slip capacity, and the drug-loaded fibrous membrane can avoid esophageal restenosis through long-term uniform slow release of drugs, so that the life safety of a patient can be further guaranteed.

The present invention discloses a 4D printing method, apparatus, and application thereof, including processes such as proportioning of multi-viscosity liquid components, flow mixing, degassing, temperature-controlled curing, filling, and final curing. Based on an integrated molding design concept, the method enables the preparation of pneumatically driven, self-propelled, deformable bionic structures (referred to as "bionic deformable actuators"). The apparatus and method of the present invention can produce functional components made of elastic, flexible materials with a viscosity range of 2,000 to 38,000 cps. This greatly simplifies the preparation process of bionic deformable actuators, enabling direct printing and single-stage molding without the need for secondary processing.

The invention relates to an intelligent cerebrovascular stent based on polymer short fibers and a preparation method thereof. The method comprises the following steps: carrying out electrostatic spinning on a polymer spinning solution to obtain polymer long fibers, freezing the polymer long fibers in liquid nitrogen, and carrying out low-temperature shearing dispersion to obtain polymer short fibers; a polymer in the polymer spinning solution is at least one of polycaprolactone, polylactic acid, gelatin, cellulose, fibroin, collagen and chitosan; uniformly mixing the temperature response high-molecular polymer and the polymer short fiber to obtain a 4D printing raw material; and designing a 4D printing model of a spider-leg-imitating structure, and performing 4D printing on a 4D printing raw material to obtain the intelligent cerebrovascular stent. According to the preparation method, the intelligent cerebrovascular stent with the spider-leg-imitating structure is prepared, the spider-leg-imitating structure design and the introduction of the polymer short fibers can endow the cerebrovascular stent with better shape adaptability and intelligent responsiveness, and the mechanical property and the anti-skid property of the cerebrovascular stent are effectively improved.

The present application relates to the field of intelligent protection, and particularly relates to a 4D printing system and method of a bionic energy-absorbing honeycomb structure with adjustable configuration, which can consider deformation and efficient energy absorption when facing different collision conditions, fully protect the integrity of the passenger cabin or cargo cabin, and effectively reduce the injury of passengers or goods. The printing device contains a double-material extrusion system, a control system and a dynamic forming platform. The double-material extrusion system integrates a digital magnetic control system with an auxiliary magnetic field material extrusion system. In the printing process, by planning the printing path and applying a magnetic field, a patterned ferromagnetic domain pattern can be obtained while forming a complex honeycomb structure. Under the coupling effect of a high-frequency induction heater and a driving magnetic field, combined with the dynamic chemical properties of the base material, the obtained honeycomb structure can adjust the cell structure and material stiffness of the honeycomb material to cope with different collision conditions, realize active intelligent protection, and has great application potential in the field of transportation.

The invention relates to the technical field of medical implants, in particular to a 4D printing-based porous Niti alloy bionic bone gradient structure construction method, which comprises the steps of patient bone data acquisition, bionic gradient model design, NiTi powder preparation, 4D printing, thermal treatment activation of memory effect, surface functionalization treatment and mechanical / biological performance test. The method is characterized by comprising the following preparation steps: accurately acquiring bone structure data through CT / MRI, combining Mimics pretreatment and UG / NX modeling, designing aperture and porosity for differentiation of cortical bone (low porosity of 30%-40%) and cancellous bone (high porosity of 50%-70%), simulating typical load working conditions through ANSYS, enabling the elastic modulus (3-15 GPa) and compressive strength (80-200 MPa) to be close to natural bone, and finally obtaining the bone structure data through the CT / MRI, the pore diameter and porosity of the cortical bone (low porosity of 30%-40%) and the porosity of the cancellous bone (high porosity of 50%-70%). According to the design, the elastic modulus difference between the implant and the host bone is remarkably reduced, the bone resorption problem caused by stress shielding is avoided, meanwhile, continuous porosity transition is achieved through the power gradual change technology, and the structural stability under the complex load is improved.

The invention discloses 3D printing direct writing ink capable of intelligently responding to hydrogel, which comprises the following components in parts by weight: 100 parts of water; 0.5 to 2.8 parts of carbomer; 6.8 to 18 parts of a hydrogel monomer N-isopropylacrylamide; 0.001 to 0.006 part of sodium hydroxide serving as a pH regulator; 0.005 to 0.02 part of a cross-linking agent, namely methylene bisacrylamide; 0.00625 to 0.0125 part of ammonium persulfate serving as an initiator; 0.00125 to 0.00375 parts of pyrrole; carbomer serves as a dispersing agent to inhibit pyrrole molecule agglomeration, pyrrole and an initiator ammonium persulfate have a synergistic effect in a polymerization reaction, a polypyrrole photo-thermal phase is generated in situ, thermal polymerization and crosslinking of a hydrogel monomer N-isopropylacrylamide are initiated, and a uniformly dispersed double-gel network is formed; through optimization of synergistic polymerization of pyrrole and ammonium persulfate and design of a carbomer dispersant, in-situ uniform dispersion of a photo-thermal phase and synchronous crosslinking of a gel network are realized, the photo-thermal conversion efficiency and material uniformity are improved, use of a toxic coagulant is avoided, the window period of 3D printing is prolonged, swelling deformation is inhibited, and the material is suitable for the fields of intelligent 4D printing, drug loading and bionic robots.

The invention provides a 4D printing path planning method based on fiber orientation and layering sequence, and relates to the technical field of intelligent additive manufacturing, and the method comprises the following steps: designing a two-dimensional plane precursor model according to a target three-dimensional structure, and dividing a deformation area and a non-deformation area; differentiated printing paths and material layouts are planned for different areas, material anisotropy is programmed by setting the movement angle of a printing spray head, and the stacking sequence and the thickness proportion of material layers are controlled; a multi-material composite printing process is adopted, PLA is deposited in the deformation area, and PETG is deposited in the non-deformation area; and finally, applying thermal stimulation at 70-75 DEG C to the component, so that the component is autonomously deformed into a three-dimensional functional component from a two-dimensional plane. Structural integrated manufacturing is achieved, deformation is accurate and controllable, interface combination is reliable, and the light weight and assembly efficiency is remarkably improved.

The invention discloses a shape memory alloy bone scaffold imitating a Haversian system as well as a 4D printing preparation method and application of the shape memory alloy bone scaffold. According to the 4D printing preparation method, the stress state and function requirements of the bone scaffold are fully considered, a bone scaffold porous structure with an imitated Haversian system is designed by adopting a function bionic method, and the bone scaffold is prepared by adopting a 4D printing technology. The inner layer imitated cancellous bone porous structure designed in the preparation method not only meets the requirement that the inner layer has good elasticity and toughness, but also facilitates cell adhesion to guide cell growth and maintains blood supply; the designed artificial cortical bone porous structure with the Haversian system on the outer layer meets the requirement that the outer layer has good compression resistance and bending resistance, and the Haversian system is more beneficial to ingrowth of blood vessels and nerves and maintains skeleton metabolism and repair. The shape memory alloy bone scaffold simulating the Haversian system, disclosed by the invention, has a wide application prospect in the field of bone implants.

The invention discloses high-thermal-conductivity fiber toughened fluorescent ceramic as well as a preparation method and application thereof, and aims to solve the problems of brittle fracture and thermal quenching of traditional fluorescent ceramic. According to the method, a pre-strain programmable 4D printing technology is adopted, and aluminum nitride (AlN) short fibers and carboxymethyl cellulose are self-assembled to form a natural concentric cylinder microstructure, so that the toughness and the mechanical property of the ceramic are enhanced. The strain distribution of the rubber film in a tensile state is simulated through finite element analysis, and the stress direction and the deformation control of a key area are optimized. Pre-strain is applied to the rubber film, and a fluorescent ceramic biscuit is printed on the surface of the rubber film; after the stress is released, the ceramic body spontaneously deforms into a hollow hemispherical structure. A rubber substrate is removed through high-temperature sintering, and the fluorescent ceramic with high mechanical strength and high thermal conductivity is obtained. The bending strength of the fiber-toughened fluorescent ceramic reaches 500-600 MPa, and the fracture toughness is improved to 9-11 MPa.m / , so that the fiber-toughened fluorescent ceramic is obviously superior to the traditional fluorescent ceramic.

The invention relates to a 4D printing bionic artificial limb and a preparation method and application thereof, and relates to the technical field of medical rehabilitation instruments, the bionic artificial limb comprises a bionic skeleton and a flexible driving unit; the flexible driving unit is located at a joint moving part of the bionic skeleton and is used for driving the bionic skeleton to move; the bionic artificial limb is integrally formed through 4D printing, the bionic skeleton is made of a shape memory composite material, and the flexible driving unit is made of a hydrogel driving material; the shape memory composite material comprises a shape memory polymer and a reinforcing material in a mass ratio of (80-95%): (5-20%); the hydrogel driving material comprises a thermo-sensitive polymer matrix, a stabilizer and a functional filler in a mass ratio of (50%-80%): (20%-40%): (3%-15%). The 4D printing bionic artificial limb has the dynamic adjusting capacity, and the change requirements of the residual limb under different conditions can be met.

The invention belongs to the field of bionic soft robots, and particularly relates to a near-infrared light driven 4D printing bionic soft robot for underwater operation, and a preparation method of the near-infrared light driven 4D printing bionic soft robot comprises the following steps: adding graphene oxide into water, and carrying out ultrasonic treatment; adding an N-isopropylacrylamide monomer, N, N '-methylene bisacrylamide and phenyl (2, 4, 6-trimethylbenzoyl) lithium phosphate, and carrying out ultrasonic treatment; adding lithium bentonite to obtain ink; quickly stirring until the ink is inverted and does not flow to obtain the GO-NIPAM ink capable of being used for 3D printing; the GO-NIPAM ink is loaded into a charging barrel for 3D printing, a 3D printing model is of a starfish-imitating structure, and the GO-NIPAM ink of the starfish-imitating structure is obtained; ultraviolet light is used for curing, and GO-PNH hydrogel is obtained; and soaking in a 0.1-0.3 M hydrazine hydrate aqueous solution, and then soaking in deionized water to obtain the 4D printing bionic soft robot based on rGO-PNH. The 4D printing bionic soft-bodied robot has quick, stable and repeatable near-infrared light response, can execute grabbing and releasing actions, and can adapt to an underwater working environment.

The invention provides an intelligent full-automatic adjustable 4D (four-dimensional) printing distal radius splint, which belongs to the technical field of medical instruments and comprises a first splint, a second splint, a third splint and a fourth splint which are sequentially arranged in a ring shape. Miniature tension sensors are arranged between the two first bandages on the first small clamping plate and the fourth small clamping plate and between the two first bandages on the second small clamping plate and the third small clamping plate, the winding piece is connected with the other ends of the second bandages, and the sides, close to each other, of the third small clamping plate and the fourth small clamping plate are fixedly connected with a pair of third bandages. The two third bandages, right opposite to each other, on the third small clamping plate and the fourth small clamping plate are connected through a connecting piece. The problems that after an existing 4D printing distal radius splint is used for fixing a fracture part for a period of time, the splint is loosened, it cannot be guaranteed that the splint is always clamped on an affected part with proper force, a patient needs to go to a hospital for adjustment, time and labor are consumed, and use is very inconvenient are solved.

The invention discloses a preparation method and system of an intelligent joint rehabilitation brace based on 4D printing and customizable force feedback, and the method comprises the steps: determining a structural form adaptive to 4D printing according to the structure of a joint part, and pre-determining structural parameters in the structural form and a mapping relation between key structural parameters and force feedback, the model is embedded into model design software, and key structure parameters of the model can be correspondingly adjusted according to the mapping relation and force feedback needed by rehabilitation to obtain a brace sheet model; a three-dimensional structure is formed through 4D printing, and the intelligent joint rehabilitation brace is obtained after adjustment. Compared with a traditional brace manufacturing technology, the manufactured intelligent hand brace is lower in cost and higher in manufacturing speed and can have the function of sensing the force feedback magnitude of a patient in real time.

The present invention relates to a highly conjugated photocurable discotic liquid crystal monomer based on benzotrithiophene-bridged carbazole and its application in 4D printing intelligent manufacturing, belonging to the technical field of liquid crystal materials. The structural general formula is as shown in Formula (I). In the present invention, carbazole and thiophene groups with good optoelectronic response are introduced into the photocurable liquid crystal molecular system to replace the low-conjugated phenyl structure bridged by traditional ester bonds, which not only realizes a lower driving voltage for 4D printing structures, but also the position of carbazole-NH is convenient for introducing flexible side chains, further realizing the regulation of the phase transition temperature of liquid crystal materials.

The invention discloses an electromagnetic wave emission method and an integrated reconfigurable metasurface based on 4D printing, and belongs to the technical field of microwaves. The electromagnetic wave emission method comprises the following steps: acquiring a target voltage; based on the target voltage, controlling the 4D switch to deform towards a target direction, and obtaining equivalent capacitance corresponding to the deformed 4D switch; and based on the equivalent capacitance, regulating and controlling an electromagnetic wave signal and controlling the radiating surface to emit the electromagnetic wave signal. According to the electromagnetic wave emission method, the electromagnetic wave signal can be regulated and controlled by applying the voltage based on the requirement, the requirements of various application scenes can be met, the weight and cost of the reconfigurable array antenna are reduced, and the manufacturing process is simplified.

The invention provides a manufacturing process of a micro supercapacitor based on femtosecond laser 4D printing, which relates to the technical field of energy storage device manufacturing, and comprises the following steps: providing a substrate which is glass, a silicon wafer, a polymer film or a metal foil, and pre-treating the surface of the substrate to obtain a pre-treated substrate; and the pretreated substrate is coated with carbon quantum dots and shape memory epoxy resin to form a composite material layer. According to the manufacturing process of the micro supercapacitor based on femtosecond laser 4D printing, a femtosecond laser technology is combined with optical flow control printing and infrared laser irradiation, a porous structure can be accurately constructed in a composite material layer, a deformation state is solidified and fixed through infrared laser, and a novel manufacturing method of the micro supercapacitor is provided; a high-precision miniature capacitor structure is realized, and the energy storage capability and the cycling stability of the capacitor are effectively improved.

The utility model discloses an in-situ preheating device for a 4D printing composite material, and relates to the technical field of 4D printing. The wire cutting device comprises a mounting seat, a laser head is fixedly mounted on the outer surface of the mounting seat, a support is fixedly mounted at the top of the mounting seat, an adjusting assembly and a wire feeding assembly are arranged on the outer surface of the support, a wire cutting assembly is arranged at the bottom of the mounting seat, and a clamping assembly is arranged on the outer surface of the wire cutting assembly. The adjusting assembly is used for adjusting the size of the wire feeding assembly, and the wire feeding assembly is used for driving the prepreg wires to conduct movable wire feeding. Through connection of the adjusting assembly and the wire feeding assembly, when the adjusting assembly is rotated, the adjusting assembly converts rotary motion into linear motion and pushes the wire feeding assembly to do linear motion at the same time, so that the wire feeding assembly can be folded or separated, and gaps in the wire feeding assembly are changed; therefore, the wire feeding assembly can be in close contact with different prepreg wires to ensure the accuracy of a wire feeding path.

The present application relates to the technical field of materials, in particular to a multi-stage solidification shape memory polymer for 4D printing and a preparation method thereof. In view of the problem that it is difficult to build gradient mechanical functions by precisely regulating the structure modulus in a single structure of 4D printing, the present application obtains a single-component multi-stage solidification shape memory polymer by regulating the ratio of toluene-2, 4-diisocyanate-hydroxypropyl acrylate, shape memory polymer, polyethylene glycol 400 and 1, 3, 5-tris (6-isocyanate hexyl) -1, 3, 5-triazine-2, 4, 6-trione under the test feedback of the printing structure modulus, and solves the problem that it is difficult to build gradient mechanical properties in a single structure of 4D printing.

A printable shape memory polymer composition for use in fabricating a 4D printed dental aligner is provided The composition comprises a first (meth)acrylate monomer, a second (meth)acrylate monomer which provides transient crosslinks to the printable shape memory polymer composition, one or more crosslinkers, and a photoinitiator, wherein the printable shape memory polymer composition is responsive to change in temperature at temperature Tg to become flexible, allowing the printable shape memory polymer composition to be shaped and reshaped at temperature Tg. A 4D printed dental aligner comprising the printable shape memory polymer composition is also disclosed.

This invention relates to the field of printer nozzle technology, and more particularly to a high-precision FDM 4D printing nozzle for metal-plastic functional graded structures. The nozzle includes a first feeding device, two second feeding devices, a feeding connector, a water cooling device, a melting and stirring device, a feeding conduit shell, and multiple filament guides. This invention solves the problems of poor material mixing uniformity in existing technologies. In the design and fabrication of plastic functional graded structures, the composite precision and segregation of the plastic directly affect the performance and interface quality of the functional graded structure. Current plastic functional graded structure designs mainly focus on different material content ratios, requiring material design to be completed before molding. This results in a small range of material variability and poor flexibility. Furthermore, uneven plastic mixing directly causes inconsistencies between the functional graded structure performance and the design, severely leading to interface cracking and molding failure.

The invention provides a preparation method of a PLA / TPU based 4D printing composite material. The method comprises the following steps: weighing PLA, TPU, dicumyl peroxide (DCP) and maleic anhydride grafted polyethylene (MAH-g-PE) according to a specific ratio; drying the raw materials; carrying out melt blending and granulation in a specific temperature interval through a double-screw extruder; and finally, extruding the composite granules to prepare the printing wire material with the standard diameter. According to the method, through optimized process steps and parameters, the synergistic effect of the DCP cross-linking agent and the MAH-g-PE compatibilizer in the processing process is effectively promoted, and cross-linked network construction and interface compatibility are synchronously completed through a one-step method. The prepared composite wire is stable in specification and good in printing adaptability, the finally obtained 4D printing product has the advantages of being compact in interface bonding, excellent in shape memory performance and balanced in mechanical property, and the method is good in repeatability and suitable for industrial application.

A 4D printing intelligent structure design method based on a convolutional neural network comprises the following steps: parametric modeling and data generation: controlling finite element software through a script to construct a'material parameter field-target deformation field 'sample data set in batches; data preprocessing and geometric standardization: uniformly converting a complex design domain into a standard rectangular domain by adopting a conformal mapping technology, and realizing high-fidelity standardization of physical field data; constructing a U-Net + ResNet hybrid convolutional neural network, and combining with composite loss function training to synchronously optimize global and key region deformation prediction precision; performing standardization processing on the new design after model deployment to realize second-level high-precision deformation prediction; the physical space design is restored through inverse mapping, multi-material 4D printing manufacturing is driven, and a deformation verification closed loop is completed. According to the method, the limitation of complex geometric boundaries is broken through, the nonlinear and multi-physics field coupling characteristics of the intelligent material can be accurately represented, and the practicability of the scheme is ensured by the constructed'design-prediction-manufacturing 'integrated process.

The application discloses a kind of soft material 4D printing method and device with regionalized magnetic domain direction.The method comprises the following steps: establishing partition three-dimensional model and planning printing path to generate original G code;Based on the preset magnetic domain direction requirement, obtain the driving parameters of multiple magnetic poles by magnetic field model reverse decoupling, and re-edit G code to integrate magnetic field control and UV light control instruction;Prepare UV-curable soft material containing magnetic particles;After setting printing parameters, execute printing, synthesize three-dimensional magnetic field of preset direction at extrusion point when material extrusion makes magnetic particles directional, and delay to open UV light curing to lock magnetic domain direction.The application realizes three-dimensional space regionalization editing of magnetic domain direction inside soft material, significantly improves the deformation design freedom and motion control accuracy of 4D printing product, and provides reliable technical support for integrated manufacturing of complex driven soft robot.