4 May 2026

An Investigation of Causes of Inaccuracy of Infrared Radiation Cameras for Large-Scale Additive Manufacturing Applications

Abstract: In additive manufacturing, accurate temperature data are needed for both real-time feedback for print operators and understanding the thermomechanical behavior for prediction and part quality characterization. Through the collection of accurate temperature data, thermal models can be validated to predict process-induced properties of parts. Infrared radiation (IR) is used to determine the temperature of a surface. Because IR cameras measure thermal radiation from a distance without contact, they are safe to use in high-temperature environments like 3D printing. An investigation of reported temperature values for multiple cameras during one print showed a decreasing trend for cameras close to the printer’s heat sources, which was not reflective of the printing process, and a discrepancy of ±20°C when printing at 200°C across overlapping camera views. Two more prints were studied to determine whether this camera behavior was unique to that print and geometry. The analysis showed the same results across all three prints, with camera-reported values having inconsistencies for a single layer, a subset of layers, and the scale of the print. Multiple possibilities for the cameras’ variances were explored. The IR cameras were determined to require further calibration and experimentation before reported temperature values can be treated as physical temperature values.

8 Apr 2026

Phase-pure Formamidinium Lead Iodide Perovskite Films Deposited via Flow-Limited Field-Injection Electrostatic Spraying

Abstract: Phase-pure perovskite formamidinium lead iodide (FPI) films were deposited using flow-limited field-injection electrostatic spraying at a deposition temperature of 120 ○C without employing stabilizing additives while retaining large-area scalability. The structures of the films were analyzed using the Rietveld refinement of x-ray diffraction measurements, enabling achievement of phase purity under optimized charging voltage and deposition temperature. The effect of precursor molar ratio on the phase of FPI was investigated by Fourier transform infrared spectroscopy, revealing the crucial role of the FAPbI3 ⋅ DMSO adduct formed in solution for achieving phase purity. Optical properties and photoactivity were assessed by absorption spectroscopy and time-resolved photoluminescence, demonstrating viability for application to solar cells.

19 Sep 2025

Design and Development of Large Format Additive Manufacturing Techniques

Abstract: This report discusses the creation of a large format additive manufacturing (LFAM) printer and initial test printing with the machine. A pellet-extruder head was attached to a computer numerical control (CNC) gantry. The team at the US Army Research and Development Center (ERDC) modified gantry arms to increase build height and designed electronic controls to allow for control of the printhead and the heated print bed. This report also covers print parameter optimization and print settings development.

18 May 2020

PUBLICATION NOTICE: Phase-Field Simulations of Solidification in Support of Additive Manufacturing Processes

Abstract: For purposes relating to force protection through advancments in multiscale materials modeling, this report explores the use of the phase-field method for simulating microstructure solidification of metallic alloys. Specifically, its utility was examined with respect to a series of increasingly complex solidification problems, ranging from one dimensional, isothermal solidification of pure metals to two-dimensional, directional solidification of non-isothermal, binary alloys. Parametric studies involving variations in thermal gradient, pulling velocity, and anisotropy were also considered, and used to assess the conditions for which dendritic and/or columnar microstructures may be generated. In preparation, a systematic derivation of the relevant governing equations is provided along with the prescribed method of solution.