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Search Publications by: Orion Kafka (Fed)

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Displaying 1 - 16 of 16

Investigation of melt pool dynamics and solidification microstructures of laser melted Ti-6Al-4V powder using X-ray synchrotron imaging

April 10, 2024
Nicholas Derimow, Madelyn Madrigal-Camacho, Orion Kafka, Jake Benzing, Edward Garboczi, Samuel J. Clark, Suveen Mathaudhu, Nik Hrabe
Titanium alloy (Ti-6Al-4V) is widely used in additive manufacturing (AM) industry. However, as laser powder-bed fusion (PBF-L) additive manufacturing (AM) advances towards reliable production of titanium parts, a thorough understanding of the process

Evidence for contributions of lack-of-fusion defects and dislocations to acoustic nonlinearity and loss in additively manufactured aluminum

February 2, 2024
Ward L. Johnson, Paul R. Heyliger, Jake Benzing, Orion Kafka, Newell Moser, Derek Harris, Jeremy Iten, Nik Hrabe
Resonant acoustic nonlinearity and loss have previously been found to be correlated with porosity in additively manufactured (AM) commercially pure aluminum and stainless steel, and this effect offers a potential basis for rapid nondestructive

AM Bench 2022 Macroscale Tensile Challenge at Different Orientations (CHAL-AMB2022-04-MaTTO) and Summary of Predictions

January 16, 2024
Newell Moser, Jake Benzing, Orion Kafka, Jordan Weaver, Nicholas Derimow, Ross Rentz, Nik Hrabe
The additive manufacturing benchmarking challenge described in this work was aimed at the prediction of average stress–strain properties for tensile specimens that were excised from blocks of non-heat-treated IN625 manufactured by laser powder bed fusion

Enhanced strength of additively manufactured Inconel 718 by means of a simplified heat treatment strategy

October 27, 2023
Jake Benzing, Nicholas Derimow, Orion Kafka, Nik Hrabe, Philipp Schumacher, Don Godfrey, Chad Beamer, Priya Pathare, Jay Carroll, Ping Lu, Isaiah Trujillo, Frank DelRio
This study simplified the heat treatment route and reduced the post-processing burden for laser powder bed fusion IN718 (a nickel-based superalloy). The tailored route retained advantageous microstructures and improved tensile strength when compared to the

Unintended consequences: Assessing thermo-mechanical changes in vinyl nitrile foam due to micro-computed X-ray tomographic imaging

October 5, 2023
Alexander Landauer, Zois Tsinas, Orion Kafka, Newell Moser, Jack Leigh Glover, Aaron M. Forster
Micro-computed X-ray tomography (μCT) is a volumetric imaging tool used to quantify the internal structure of materials. μCT imaging with mechanical testing (in situ μCT) helps visualize strain-induced structural changes and develop structure-property

Effects of as-built surface with varying number of contour passes on high-cycle fatigue behavior of additively manufactured nickel alloy 718

August 5, 2023
Orion Kafka, Jake Benzing, Nicholas Derimow, Philipp Schumacher, Lucas Koepke, Chad Beamer, Donald Godfrey, Nik Hrabe
High cycle fatigue life of laser-powder bed fusion (L-PBF) parts depends on several factors; as-built surfaces, when present, are a particular concern. This work measures as-built L-PBF surfaces with X-ray computed tomography, and uses rotating beam

A Materials Data Framework and Dataset for Elastomeric Foam Impact Mitigating Materials

June 5, 2023
Alexander Landauer, Orion Kafka, Newell Moser, Ian Foster, Ben Blaiszik, Aaron M. Forster
The availability of materials data for impact-mitigating materials has lagged behind applications-based data. For example, data describing on-field helmeted impacts are available, whereas material behaviors for the constituent impact mitigating materials

X-ray computed tomography analysis of pore deformation in IN718 made with directed energy deposition via in-situ tensile testing

August 28, 2022
Orion Kafka, Cheng Yu, Puikei Cheng, Sarah Wolff, Jennifer Bennett, Edward Garboczi, Jian Cao, Xianghui Xiao, Wing Kam Liu
Directed energy deposition (DED) is a metal additive manufacturing technique often used for larger-scale components and part repair. It can result in material performance that differs from conventionally processed metal. This work studies spatial and

Assessment of intra-build variations in tensile strength in electron beam powder-bed fusion Ti-6Al-4V part 1: Effects of build height

June 2, 2022
Nicholas Derimow, Alejandro Romero, Aldo Rubio, Cesar Terrazas, Newell Moser, Orion Kafka, Jake Benzing, Francisco Medina, Ryan Wicker, Nik Hrabe
In this work, rectangular blocks of electron beam powder-bed fusion (PBF-EB) additively manufactured (AM) Ti-6Al-4V were built, such that a total of 68 mini-tensile test coupons could be extracted for mechanical testing over a range of build height and

Assessment of intra-build variations in tensile strength in electron beam powder-bed fusion Ti-6Al-4V part 2: Effects of powder mixing

May 31, 2022
Nicholas Derimow, Jake Benzing, Orion Kafka, Newell Moser, Priya Pathare, Michael Walker, Frank DelRio, Nik Hrabe
In Part 2 of this paper series, high-throughput tensile testing and characterization of porosity, microstructure, and oxygen content was carried out on Ti-6Al-4V samples that were fabricated via electron beam powder-bed fusion (PBF-EB) to test our

Evaluation of a Modified Void Descriptor Function to Uniquely Characterize Pore Networks and Predict Fracture Location in Additively Manufactured Metals

November 15, 2021
Dillon Watring, Jake Benzing, Orion Kafka, Li-Anne Liew, Newell Moser, John Erickson, Nik Hrabe, Ashley Spear
Variations in additive manufacturing (AM) processing parameters can lead to variations in porosity, making it challenging to predict pore- or void-sensitive mechanical response in AM metals. A recently developed pore metric, the void descriptor function