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An additive manufacturing system having a heat source for melting powder particles in a desired shape and pattern to produce a product. A secondary heat source is used for heat treating the product to achieve heat treatment. The secondary heat source is used to peen or anneal residual stresses caused by the additive manufacturing process.
An additive manufacturing system and method for forming a part of dissimilar materials. The additive manufacturing system may include a build platform, a recoater for dispensing build powder onto the build platform, an energy source, a foil feed assembly, and a controller for controlling actuation of these components. The method of forming the part may include the steps of depositing a layer of build powder onto the build platform surface, melting selected portions of the layer of build powder, applying a sheet of foil over the layer of build powder, melting selected portions of the sheet of foil onto the layer of build powder, removing the sheet of foil from the layer of build powder, and then lowering the build platform surface to prepare for deposition of a next layer of the build powder. These steps are then repeated one or more times, thereby forming the part.
A method for producing a composite polymeric article, an additive for a polymeric article, and a composite polymeric article are provided. The method generally includes providing a plurality of graphene nanoplatelets, providing a plurality of silica nanofibers, providing a polymeric material, and distributing the plurality of silica nanofibers and the plurality of graphene nanoplatelets within the polymeric material to achieve a composite article. The additive for a polymeric article includes a plurality of graphene nanoplatelets and a plurality of silica nanofibers. The composite polymeric article includes a plurality of graphene nanoplatelets, a plurality of silica nanofibers, and a polymeric matrix. The plurality of graphene nanoplatelets and the plurality of silica nanofibers are distributed within the polymeric matrix. The silica nanofibers have a mean cross sectional diameter of not more than 100 nm.
A method for producing magnet-polymer pellets useful as a feedstock in an additive manufacturing process, comprising: (i) blending thermoplastic polymer and hard magnetic particles; (ii) feeding the blended magnet-polymer mixture into a pre-feed hopper that feeds directly into an inlet of a temperature-controlled barrel extruder; (iii) feeding the blended magnet-polymer mixture into the barrel extruder at a fixed feed rate of 5-20 kg/hour, wherein the temperature at the outlet is at least to no more than 10° C. above a glass transition temperature of the blended magnet-polymer mixture; (iv) feeding the blended magnet-polymer mixture directly into an extruding die; (v) passing the blended magnet-polymer mixture through the extruding die at a fixed speed; and (vi) cutting the magnet-polymer mixture at regular intervals as the mixture exits the extruding die at the fixed speed. The use of the pellets as feed material in an additive manufacturing process is also described.
This invention relates to a method for preparing an electrochemical cell comprising the sequential steps of preparing a solution of a lithium salt in an non-aqueous solvent containing an additive compound, and maintaining the solution at a temperature in the range of about 20 to about 30° C. for about 5 to 10 days to form an aged electrolyte; assembling an electrochemical cell from an anode, a cathode, and the aged electrolyte; and electrochemically subjecting the electrochemical cell to formation cycling. The additive compound comprises one or more compounds selected from the group consisting of: (R3SiO)3B, (R3SiO)3XY, (R3SiO)3P, (R′O)3PO, (R3Si)3X′, R3SiOS(O)2R′; (R3Si)OC(═O)R′; wherein each R and R′ independently is a hydrocarbyl group; X is P or B; Y is O or S; X is Ti or Al. Electrochemical cells and batteries also are described.
Methods of additive manufacture using coreactive components are disclosed. Thermosetting compositions for additive manufacturing are also disclosed.
An additive manufacturing system and method for forming a part of dissimilar materials. The additive manufacturing system may include a build platform, a recoater for dispensing build powder onto the build platform, an energy source, a foil feed assembly, and a controller for controlling actuation of these components. The method of forming the part may include the steps of depositing a layer of build powder onto the build platform surface, melting selected portions of the layer of build powder, applying a sheet of foil over the layer of build powder, melting selected portions of the sheet of foil onto the layer of build powder, removing the sheet of foil from the layer of build powder, and then lowering the build platform surface to prepare for deposition of a next layer of the build powder. These steps are then repeated one or more times, thereby forming the part.
Additively manufactured metals differ from their conventionally produced counterparts due to the inherent material inhomogeneity, porosity, and thermal stress induced by the process. These differences make the machining of additively manufactured metals more difficult and cause premature tool failure or unexpected surface finish at certain conditions. This study takes the first step to investigate and identify the causes of these issues, particularly for Ti-6Al-4V. Printed and wrought samples, as well as heat treatment effect, are compared in a dry cutting condition at a cutting speed of 90 m/min in terms of cutting power, vibration, temperature, and produced surface finish. The results show a lower cutting power and more vibration for as-printed Ti samples, indicating a less ductile microstructure and inclusion of pores. Heat treatment can eliminate these phenomena. There is no significant difference found in the produced surface finish at the current cutting condition.
An additive manufacturing system and method for forming a part of dissimilar materials. The additive manufacturing system may include a build platform, a recoater for dispensing build powder onto the build platform, an energy source, a foil feed assembly, and a controller for controlling actuation of these components. The method of forming the part may include the steps of depositing a layer of build powder onto the build platform surface, melting selected portions of the layer of build powder, applying a sheet of foil over the layer of build powder, melting selected portions of the sheet of foil onto the layer of build powder, removing the sheet of foil from the layer of build powder, and then lowering the build platform surface to prepare for deposition of a next layer of the build powder. These steps are then repeated one or more times, thereby forming the part.
Chemical processors are configured to reduce mass, work in conjunction with solar concentrators, and/or house porous inserts in microchannel or mesochannel devices made by additive manufacturing. Methods of making chemical processors containing porous inserts by additive manufacturing are also disclosed.
The world of beamline science is often fast-paced and dynamic. One of the major challenges in this environment is to be able to design, manufacture and then implement new items for use on the beamlines in a fast and accurate manner. Many times, this involves iterating the design to address unknown or new variables which were not pre- sent at the beginning of the project planning task. Through the use of additive manufacturing, I have been able to support the user programs of various (APS) Ad- vanced Photon Source beamlines* across multiple scien- tific disciplines. I will provide a few detailed examples of Items that were created for specific beamline applications and discuss what benefits they provided to the pertinent project. I will also talk about why choosing consumer- level printer options to produce the parts has been the direction I went and the pros and cons of this decision. Pri marily, this choice allowed for quicker turnaround times and the ability to make more frequent changes in an efficient manner. Currently, we are utilizing only the fused deposition modelling (FDM) type printers but I am exploring the addition of UV-activated resin printing, exotic materials that can be utilized using the current toolset, and the possibility of commercial metal printing systems. This technology has been a game-changer for the implementation of new support items and instrumentation over the last couple of years for the different disciplines I am sup- porting. I will discuss how the roadmap ahead and what the evolving technologies could potentially allow us to do.
Additively Manufactured Interpenetrating Composites (AMIPCs) are a relatively new metal-metal chain composite in development for use in high energy absorption systems. In this system, reinforcing phase of additively manufactured continuous lattice configurations 316L austenitic stainless-steel is in melt infiltrated with a matrix phase of A356 aluminum-silicon casting alloy. Measurements and observations of this material system have shown that weakly bonded or open/porous interface between the reinforcement and matrix phases exhibits dramatically different mechanical properties of AMIPCs, which is not currently well understood. In this work, Finite Element Models (FEM) are used to model the effects of interfaces between the composite phases. Mechanical tensile tests measurements of various composite volume fractions and varying degrees of casting infiltration are also examined and used to show consistency with the FEM results. The outcome provides insight into material design criteria and performance predictions for new hybrid material systems with exceptional damage tolerance.
Big Area Additive Manufacturing (BAAM) technology allows for manufacturing of large-scale objects with a potential to reduce energy embedded in products, reduce or eliminate energy necessary for transportation of goods along with reducing the lead time and cost in some cases. Over the last few years, Oak Ridge National Laboratory (ORNL) has been focusing on large-scale printing of single material systems, typically un-reinforced or short fiber reinforced polymers, in order to address needs in stiffness-limited applications. This paper describes the development of a multi-material large-scale AM system through a collaboration with Cincinnati Inc. and Performance Feed Screw Inc. Modifications to the Big Area Additive Manufacturing (BAAM) system includes a new extruder design to accommodate a dual feed system, an expanded two-dryer system with a capacity of 273 kg/dryer, and a system that is capable of mixing pelletized materials up to 60Kg/hr. This article highlights the advantages and limitations of the multi-material system as well as potential applications.
Described herein is an additive manufacturing apparatus that is well-suited for constructing piezoelectric sensors. The additive manufacturing apparatus includes an extrusion nozzle formed of a conductive material such as aluminum. The extrusion nozzle has a channel by way of which printing material exits the extrusion nozzle, wherein a build plate is configured to receive the printing material responsive to the printing material exiting the extrusion nozzle. An arc suppressor formed of a semiconductor is coupled to the extrusion nozzle and is configured to dissipate excess charge that would otherwise exist on the extrusion nozzle when a relatively high bias voltage is applied to the extrusion nozzle. Thus, the arc suppressor mitigates arcing between the extrusion nozzle and the build plate. Arc suppressing gas is also optionally introduced into a printing region, thereby further mitigating arcing between the extrusion nozzle and the build plate.
A metal film for use by an additive manufacturing apparatus is described herein. The metal film has a support structure and metal voxels removably attached to the support structure by respective junctions. When a metal voxel in the metal film is impacted by an energy pulse from an energy source of the additive manufacturing apparatus, one or more junctions that attach the metal voxel to the support structure are broken, resulting in the metal voxel detaching from the metal film (at a desired location in a two-dimensional plane).
Direct-fired supercritical CO2 (sCO2) power cycles are being commercialized to revolutionize fossil energy as a low-emission power source. However, the cycle will increase O2 and H2O in the sCO2 and the implications of these additions have not been fully studied, particularly for lower cost steels that are needed in the lower temperature segments of the plant. Representative 9 and 12%Cr ferritic-martensitic (FM) steels and conventional and advanced austenitic steels were evaluated at 450-650°C to determine the maximum use temperatures in sCO2 with 1%O2 and 0.1%H2O at 300 bar. Compared to research grade (low impurity) sCO2 in indirect-fired cycles, the mass gains and scale thickness were not significantly changed for FM steels: both formed thick duplex Fe-rich scales. For stainless steels, higher mass gains were observed in all cases with increased Fe-rich oxide nodule formation. After 1000h at 650°C, the measured bulk C content was high for all of the steels with the addition of impurities suggesting a lower maximum operating temperature for steels. The post-exposure impact of the environment on room temperature tensile properties also will be discussed.
Additive manufacturing (AM) has the ability to produce parts with complex geometries and internal features, however, for demanding applications such as the automotive and aerospace industries, it is crucial that the parts can meet the demanding functional and geometric requirements. Quality control for AM parts focuses on nondestructive methods of testing, but many of the current methods are expensive and time-consuming. The research presented in this report explores various methods of nondestructive evaluation (NDE) using dynamic analysis on stainless steel parts produced with selective laser melting (SLM). Methods include, but are not limited to, frequency response functions (FRF), impedance-based measurements, and scanning laser doppler vibrometry. Additionally, mode shape analysis was performed in MATLAB and FEA simulations were used for comparison with experimental results. The results indicate that dynamic analysis has the potential to be a feasible method of defect detection and NDE in AM parts and future work should focus on refining these methods, such as optimizing test parameters to improve sensitivity to defects.
In this study, anisotropic stiffness tensors were reconstructed based on fiber orientation distributions obtained from X-ray computer tomography (xCT). A preform was manufactured via a big area additive manufacturing (BAAM) system with carbon fiber (CF) filled acrylonitrile butadiene styrene (ABS). The tailored preform from additive manufacturing (AM) was used in the compression molding (CM) process to produce a low-void high-performance thermoplastic composite panel. An xCT technique was employed to detect the fiber orientations in CF/ABS composites manufactured via three different methods: AM from BAAM, extrusion compression molding (ECM), and AM-CM. The anisotropic stiffness tensor was obtained from the composite panel manufactured via the three manufacturing methods (AM, ECM, and AMCM). A micromechanics theory was used to obtain the orthotropic stiffness tensors of the composite panels and compared with the experimental values. The predicted stiffness tensors of AM and AM-CM composite panels were used to study the deformation characteristics of a steering wheel during airbag deployment by performing finite element analysis (FEA). The approach developed in this study can be utilized for evaluating high-performance composites.