Techniques for Preventing Layering Defects in 3D Printing

3D printing metal objects without warping or cracking by using a tacky polymer substrate. The process involves spreading a layer of metal particles over a polymer substrate with low thermal conductivity and melting the unmasked metal with pulsed light to form each layer of the object. The polymer substrate reduces lateral heat transfer during melting, preventing warping and cracking.

Using a statistical learning model to inspect camera images of each layer during 3D printing to detect layer defects early and correct them before building on top. The model provides defect probabilities for each image pixel. If defects are found, the layer is reworked.

3D printing of parts with improved mechanical properties and reduced warping. The method involves using a photopolymer composite ink with a dual-cure system that enables complete curing of each layer in a 3D printed object. The composite consists of a polymer matrix, inorganic fillers, and a combination of photo and thermal initiators. The dual-cure initiators allow the composite to be partially cured by UV light after each layer is printed and then fully cured by heat. This prevents uncured resin from accumulating stress and warping the part.

In-situ quality testing of additively manufactured components during production to detect defects like cracks or delamination and prevent fabrication of flawed parts. The process involves mechanically exciting constructed layers of the component and measuring the mechanical response. If the response deviates from a tolerance range, indicating flaws, the production is halted. Excitation can be done using vibrations or oscillations and measurement can use pickups or sensors.

Additive manufacturing system that can detect and prevent defects during 3D printing to improve the quality of the printed objects. It does this by incorporating an in-line measurement unit that measures each layer as it is printed. The system then compares the layer measurements against reference data of a known good object to detect any deviations that could indicate an internal defect. This allows defects to be caught and corrected during the printing process rather than after completion.

Selective laser melting (SLM) additive manufacturing system that monitors layer-by-layer manufacturing of a product and adjusts control parameters during manufacturing to correct defects. It captures images of each layer before adding the next layer and then analyzes the images to identify irregularities. If found, it adjusts the laser parameters for the next layer to avoid defects like balling.

A loading system for 3D printers that reduces mounding and increases the uniformity of powder layers. The system has a loading chamber positioned over the supply container. Powder is dispensed into the chamber and compacted to increase uniformity. The chamber floor is then lowered into the supply container, transferring the compacted powder. This loading process helps distribute the powder more evenly throughout the container compared to filling it directly.

Inspecting parts during 3D printing to identify and repair defects as they occur. The method involves inspecting each layer after deposition to detect defects and repairing any defects by adding material before continuing to the next layer. The inspection can use techniques like scanning, imaging, or sensing to identify defects like voids, gaps, or misplaced material. It allows defects to be corrected in real time during manufacturing rather than after completion.

Monitoring and controlling powder deposition and melting quality in additive manufacturing to improve 3D printing accuracy and reliability. The method involves projecting structured light onto each powder layer before and after melting, imaging the light patterns to detect defects, and using the feedback to influence subsequent deposition and melting correctively.

A feedback-based correction system for additive manufacturing defects that helps repair defects on the fly during 3D printing. The system involves using real-time defect analysis during printing to scan each layer for defects and then sending correction commands to the printer to fix issues before moving on to subsequent layers.

A simple and reliable technique to enable high precision self-alignment of printed metal layers in multilayer printable electronic devices. The technique uses photonic sintering of metal nanoparticle inks to align the metal patterns. A first metal layer is printed on a transparent substrate and acts as a mask. A second metal layer is printed over a functional layer. Intense light pulses are then applied from the back of the substrate to partially sinter exposed particles, leaving aligned metal patterns. The unexposed particles are washed away.

Non-destructively inspecting additively manufactured components layer-by-layer during manufacturing using an electromagnetic acoustic transducer (EMAT) to detect anomalies like cracks and residual stress. The EMAT scans over each layer of the component being formed with an additive manufacturing head, collecting acoustic data that indicates quality. The data is compared to reference images and analyzed to detect defects.

A 3D printing method to compensate for defects caused by incomplete curing of voxels in each layer. The method involves selectively exposing the layer of uncured material based on layer data, then verifying the layer for regions of insufficiently cured material. The radiation dose is adapted for contiguous voxels in the next layer to compensate for the defects.

A manufacturing technique to dynamically correct layerwise 3D printing defects. It uses optical beams to heat and modulate the material surface in real-time during printing. Optical beams are used to control light valves and electric field modulators that modify the energy and electric fields acting on the material surface. This allows localized surface melting and shaping to correct defects, planarize surfaces, remove impurities, and add features during printing. The beams can be tuned independently to address the modulators.

A method to eliminate defects like surface roughness and sub-surface voids in 3D printed objects during the printing process itself instead of removing them after printing. The method involves partially melting each layer with a laser then removing the layer while it's still in the powder bed. This selectively removes just the layer material at the interface with the unfused powder, effectively eliminating roughness and voids that typically form there.

A data model for additive manufacturing of components to reduce distortion. The model divides the component into irregular 3D volume regions, each of which extends over multiple build layers. The regions have oblique interfaces that intersect the layers at different positions. This disrupts the layer-by-layer building process and reduces distortion by breaking up stresses. Control parameters like fill pattern and energy input can be set separately for each region or layer within regions.