Additive Manufacturing Benchmarks 2022 (AM-Bench 2022): Residual Strain/Stress and Distortion II
Program Organizers: Brandon Lane, National Institute of Standards and Technology; Lyle Levine, National Institute of Standards and Technology
Tuesday 3:30 PM
August 16, 2022
Room: Cabinet/Judiciary Suite
Location: Hyatt Regency Bethesda
Session Chair: Darren Pagan, Pennsylvania State University
3:30 PM Invited
Residual Stress Measurements in the IN718 AM-Bench Component
and a Novel Approach for Determining Three Orthogonal Components of Residual Stress by Coupling the Contour and Energy Dispersive Diffraction Techniques
: Christopher D'Elia1; Nicholas Bachus2; Lyle Levine3; Michael Hill4; 1Department of Mechanical and Aerospace Engineering, University of California; 2University Of California Davis; 3National Institute of Standards and Technology; 4University of California Davis
Providing experimental residual stress fields within additive manufactured components is required for model validation efforts. The as-built residual stress state in the IN718 AM-Bench build is assessed. Residual stresses are determined via the contour method and energy dispersive X-ray diffraction. The contour method provides component scale variations of longitudinal, build, and transverse direction stresses on four planes of interest. Unlike the prior AM-Bench builds, the IN718 build features a hollow leg. To determine its influence on the resulting residual stress field, the contour method is used to evaluate the build direction stress above the hollow leg and a neighboring solid leg. Additionally, to overcome X-ray measurement difficulties associated with the third orthogonal strain a novel approach to determining three orthogonal stress components is derived. Transverse contour stress data is combined with the longitudinaland build X-ray diffraction strain data to compute stresses in all three directions.
4:00 PM Invited
Measurement and Comparison of Residual Strain and Stress within AM-Bench Components Composed of SS15-5PH and IN625: Nicholas Bachus1; Maria Strantza2; Bjorn Clausen3; Christopher D'Elia1; Michael Hill1; Jun Young Ko4; Lyle Levine5; John Okasinski6; Jun-Sang Park6; Thien Phan5; Donald Brown3; 1University Of California Davis; 2Lawrence Livermore National Laboratory; 3Los Alamos National Laboratory; 4Cornell High Energy Synchrotron Source; 5National Institute of Standards and Technologies; 6Argonne National Laboratory
The as-built residual strain and stress states in two AM-Bench components, one composed of 15-5PH stainless steel and the other of Inconel 625, are assessed. Residual strains are determined via synchrotron source energy-dispersive diffraction, while the mechanical relaxation-based contour method is used to assess residual stress. A comparison of the residual strain and stress trends and magnitudes between the two material systems is made by normalizing results in each material by their elastic yield strain or stress limit, where these were determined from extracted tensile specimens. The two components have highly similar spatial distributions of strain and stress, but the IN625 component had roughly double the magnitude relative to its elastic limit when manufactured with the same processing conditions as the 15-5PH component. The larger residual strain and stress in the IN625 component is consistent with the non-dimensional Fourier number associated with the materials and the additive manufacturing process.
4:30 PM Invited
Part Deflection of 3D Builds of IN718 from the 2022 AM Benchmark Test Series: Maxwell Praniewicz1; J Fox1; J Tarr1; 1National Institute of Standards and Technology
This talk will discuss the deflection measurements for the 2022 AM Benchmark Test Series (CHAL-AMB2022-01-PD). The methodologies presented in this talk are identical to those also used to provide the results for the CHAL-AMB2022-02-PD. The methodology utilized to derive the uncertainty in the measurement result will first be presented to contextualize the following measurements. The measurements taken on the AM component will then be described, including the definition of the measurands, their reference frames, and the datum reference frame for positioning within the measurement system. The calibrated reference artifact utilized to determine the measurement uncertainty will then be described, along with its specific measurands. The final measurement results will then be presented. Additional measurement results captured via Focus Variation Microscopy will also be presented and contrasted against the CMM measurement results.