Abstract: A method for improving part quality in additive manufacturing involving jetting liquid metal. Limiting the amounts of magnesium and zinc in a meniscus material to below predetermined thresholds improves jetting quality. Further, ensuring an amount of Strontium is above a predetermined threshold further improves jetting of the liquid metal.

Abstract: A method for improving part quality in additive manufacturing involving jetting liquid metal. Limiting the amounts of magnesium and zinc in a meniscus material to below predetermined thresholds improves jetting quality. Further, ensuring an amount of Strontium is above a predetermined threshold further improves jetting of the liquid metal.

Abstract: For conditioning build material for fused filament fabrication, thermal power is both added to and removed from a nozzle in a manner that can reduce sensitivity of the nozzle temperature to fluctuations in build material feed rate. The amount of thermal power added is at least as large as the sum of the amount removed, the amount to condition the material, and losses to the environment. The amount removed may be at least as large as half the thermal power required to condition the material to extrusion temperature, and may be comparable to, or much larger than the conditioning amount. The larger the ratio of the amount removed to the conditioning amount, the less sensitive the nozzle temperature will be to fluctuations in build material feed rate. Fine temperature control arises, enabling building with metal-containing multi-phase materials or other materials that have a narrow working temperature range.

Abstract: 3D printing using certain materials, such as metal containing multi-phase materials can be prone to clogs and other flow interruptions. Providing build material according to feed rate profiles having varying rates can mitigate these problems. Each feed rate profile can be broken up into blocks of time, some of which relate to fabricating the exterior geometry of the object. Each block of time can be represented by a FFT. The blocks that relate to the exterior are represented by a FFT that has significant high frequency content of 1 Hz or greater. It is beneficial to use profiles including feed rates outside of a range of feed rates suitable for steady state extrusion, being either higher or lower rates than the range limits. A combination of feed rate profiles based only on clog and flow interruption mitigation and operational to print the part according to a model can be used.

Abstract: Systems, methods, and apparatus are provided for tuning a memristive property of a device. The device (500) includes a layer of a dielectric material (507) disposed over and forming an interface with a layer of an electrically conductive material (506), and a gate electrode (508) disposed over the dielectric material. The dielectric material layer includes at least one ionic species (302) having a high ion mobility. The electrically conductive material is configured such that a potential difference applied to the device can cause the at least one ionic species to migrate reversibly across the interface into or out of the electrically conductive material layer, to modify the resistive state of the electrically conductive material layer.

Abstract: Fused filament fabrication using metal based multi-phase (MBMP) build materials, creates a build with object portions and support portions adhered to each other that must be separated. Different object portions are more delicate or problematic than others. Methods for tuning or specifying the strength of adhesion at interfaces between such object and support portions include providing a release skin of powder or other material at such interfaces. Strength of adhesion also varies based on the liquid fraction of material deposited to form interfaces, generally with relatively higher liquid fraction leading to stronger adhesion. Liquid fraction is governed by MBMP material composition and temperature at deposition. Strength can be tuned by printing interfaces of the same material at different temperatures, or different materials at the same or different temperatures. Support portions may be entirely of weaker adhesion. Joining portions may separate with object or support.

Abstract: A nozzle for extruding metal containing multi phase (MCMP) build material is heated by an induction coil. The nozzle effective radius is larger than an induction skin depth in the nozzle, which is larger than 1/15 the radius, and less than the nozzle length. The nozzle material performance index, based on resistivity and magnetic permeability, is higher than that of the build material, and components of a build platform, particularly a removable sheet. The coil radius is less than 1.4 times the nozzle effective radius. The nozzle may be of several annular sections, of which that of the bore may be removable and wear resistant. The nozzle may be of multiple graphite grades, including copper infused. The coil axial extent may be less than the nozzle length, and it may be located nearer to the outlet. An adhesion control layer on a build sheet may enhance or reduce adhesion thereto.

Abstract: 3D printing using metal containing multi phase materials is prone to nozzle clogging and flow artifacts. These can be mitigated by monitoring process conditions and taking action at times based on other conditions. Forces, physical regularity, and temperatures can be monitored and service can be taken based on these, immediately, or at dynamic future points, short or longer term, such as completion of a segment or layer, or before critical geometry. Process conditions can be logged and service time can be based on functions of individual and combinations of logged data. Operating windows can be adjusted based on same. Service includes dwell time at high and low temperatures, treatment material provided into the nozzle to change the liquid composition therein. Plungers and fluid jets can expel material from nozzle inlet or outlet. Dwelling at various temperatures can liquefy clogs or cause rupture by disparate volume changes of cooling materials.

Abstract: For conditioning build material for fused filament fabrication, thermal power is both added to and removed from a nozzle in a manner that can reduce sensitivity of the nozzle temperature to fluctuations in build material feed rate. The amount of thermal power added is at least as large as the sum of the amount removed, the amount to condition the material, and losses to the environment. The amount removed may be at least as large as half the thermal power required to condition the material to extrusion temperature, and may be comparable to, or much larger than the conditioning amount. The larger the ratio of the amount removed to the conditioning amount, the less sensitive the nozzle temperature will be to fluctuations in build material feed rate. Fine temperature control arises, enabling building with metal-containing multi-phase materials or other materials that have a narrow working temperature range.

Abstract: 3D printing using certain materials, such as metal containing multi-phase materials can be prone to clogs and other flow interruptions. Providing build material according to feed rate profiles having varying rates can mitigate these problems. Each feed rate profile can be broken up into blocks of time, some of which relate to fabricating the exterior geometry of the object. Each block of time can be represented by a FFT. The blocks that relate to the exterior are represented by a FFT that has significant high frequency content of 1 Hz or greater. It is beneficial to use profiles including feed rates outside of a range of feed rates suitable for steady state extrusion, being either higher or lower rates than the range limits. A combination of feed rate profiles based only on clog and flow interruption mitigation and operational to print the part according to a model can be used.

Abstract: A rheometer has a shaft, which is supported rotatably in a gas bearing. The gas bearing has a first bearing element (rotor) attached to the shaft and a second bearing element (stator) that surrounds the first bearing element (rotor) with a distance between the two, forming a bearing gap. At least sections of the second bearing element (stator) are made from a gas-permeable material, and gas is passed through them in such manner that a gas cushion is formed in the bearing gap, by which the first bearing element (rotor) and the shaft are supported without direct contact between the two. It is provided that the first bearing element (rotor) is also made from a gas-permeable material, at least in the areas that face the second bearing element (stator), and which the gas penetrates and forms a preferably static gaseous layer close to the surface as a result of the dynamic pressure or backpressure of the gas.

Abstract: Systems, methods, and apparatus are provided for tuning a memristive property of a device. The device (500) includes a layer of a dielectric material (507) disposed over and forming an interface with a layer of an electrically conductive material (506), and a gate electrode (508) disposed over the dielectric material. The dielectric material layer includes at least one ionic species (302) having a high ion mobility. The electrically conductive material is configured such that a potential difference applied to the device can cause the at least one ionic species to migrate reversibly across the interface into or out of the electrically conductive material layer, to modify the resistive state of the electrically conductive material layer.

Abstract: Systems, methods, and apparatus are provided for tuning a functional property of a device. The device (210) includes a layer of a dielectric material (214) disposed over and forming an interface (216) with a layer of an electrically conductive target material (222). The dielectric material layer includes at least one ionic species having a high ion mobility. The target material is configured such that a potential difference applied to the device can cause the at least one ionic species to migrate reversibly across the interface into or out of the target material layer. The mobility of the at least one ionic species can be tuned by exposing the device to electromagnetic radiation and/or a temperature change.

Abstract: Systems, methods, and apparatus are provided for tuning a memristive property of a device. The device (500) includes a layer of a dielectric material (507) disposed over and forming an interface with a layer of an electrically conductive material (506), and a gate electrode (508) disposed over the dielectric material. The dielectric material layer includes at least one ionic species (302) having a high ion mobility. The electrically conductive material is configured such that a potential difference applied to the device can cause the at least one ionic species to migrate reversibly across the interface into or out of the electrically conductive material layer, to modify the resistive state of the electrically conductive material layer.

Abstract: Methods, systems, and computer-readable storage media for storing event data in an audit log file. Implementations include actions of receiving event data, determining a first signature based on the event data and an end marker, and appending the event data and the first signature to the audit log file, the first signature comprising at least a portion of a signature chain associated with the audit log file.

Abstract: Systems, methods, and apparatus are provided for tuning a functional property of a device. The device (210) includes a layer of a dielectric material (214) disposed over and forming an interface (216) with a layer of an electrically conductive target material (222). The dielectric material layer includes at least one ionic species having a high ion mobility. The target material is configured such that a potential difference applied to the device can cause the at least one ionic species to migrate reversibly across the interface into or out of the target material layer. The mobility of the at least one ionic species can be tuned by exposing the device to electromagnetic radiation and/or a temperature change.

Abstract: Embodiments described herein relate generally to a system and methods for controlling and/or modifying the degradation behavior of degradable materials via a surface treatment and/or coating. This surface treatment and/or coating (also referred to herein as a “barrier”) can be used to modify the degradation profile without changing the bulk of the degradable material. The system includes a substrate that includes a degradable material and barrier configured to protect the substrate from a foreign environment. The barrier can include a conformal coating and/or a liquid impregnated surface engineered specifically to tailor the degradation profile of the underlying substrate. Optionally, a trigger mechanism can be used to further control and/or modify the degradation behavior of the substrate.

Abstract: An improved key encryption system is provided for encrypting sensitive data on a shared data store. Various embodiments contemplate a system where a plurality of data clients are connected to one or more shared data stores. A secure data storage facility is provided on one or more of the shared data stores by using an encryption scheme. Encryption keys for decrypting the sensitive data are stored on the same data store as sensitive data, which may be decrypted using the encryption keys. To provide another layer of security, the data encryption keys are themselves encrypted using a key encryption key (“KEK”), which is generated by, and stored in a local data store associated with the data clients.

Abstract: Methods, systems, and computer-readable storage media for storing event data in an audit log file. Implementations include actions of receiving event data, determining a first signature based on the event data and an end marker, and appending the event data and the first signature to the audit log file, the first signature comprising at least a portion of a signature chain associated with the audit log file.

Abstract: Systems, methods, and apparatus are provided for tuning a functional property of a device. The device includes a layer of a dielectric material disposed over and forming an interface with a layer of an electrically conductive material. The dielectric material layer includes at least one ionic species having a high ion mobility. The electrically conductive material is configured such that a potential difference applied to the device can cause the at least one ionic species to migrate reversibly across the interface into or out of the electrically conductive material layer.