Elastic Residual Strain and Stress Measurements and Corresponding Part Deflections of 3D Additive Manufacturing Builds of IN625 AM-Bench Artifacts Using Neutron Diffraction, Synchrotron X-Ray Diffraction, and Contour Method
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One of the primary barriers for adoption of additive manufacturing (AM) has been the uncertainty in the performance of AM parts due to residual stresses/strains. The rapid heating and cooling rates from the thermal history of the laser melting process result in high residual stresses/strains that produce significant part distortion. Efforts to mitigate residual stresses using post-process heat treatments can significantly impact the microstructures of the AM part which may lead to further issues. Therefore, the ability to accurately predict the residual stresses in as-built AM parts is crucial, and rigorous benchmark measurements are needed to validate such predictions. To fill this need, the AM-Bench aims to provide high-fidelity residual stress and strain benchmark measurements in well-characterized AM bridge-shaped parts. The measurements reported here are part of the residual elastic strain benchmark challenge CHAL-AMB2018-01-RS. Residual strains and stresses in this work were measured using neutron diffraction, synchrotron X-ray diffraction, and the contour method. Part deflection measurements were performed using a coordinate measurement machine after the part was partially separated from the build plate. These independently measured results show a high degree of agreement between the different techniques.
KeywordsAdditive manufacturing Residual stress Neutron diffraction Synchrotron X-ray diffraction Contour method Nickel-based superalloy
Part of this research was supported by the Exascale Computing Project (17-SC-20-SC), a collaborative effort of the U.S. Department of Energy Office of Science and the National Nuclear Security Administration. Part of this work was performed under the auspices of the U.S. Department of Energy by Los Alamos National Laboratory, United States under Contract DE-AC52-06NA25396. Part of this work is based upon research conducted at the Cornell High Energy Synchrotron Source (CHESS) which is supported by the National Science Foundation under Award DMR-1332208. University of California, Davis, was supported by the Campus Executive program of Sandia National Laboratories.
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Conflict of interest
On behalf of all authors, the corresponding author states that there is no conflict of interest.
- 6.Levine LE et al (2019) Outcome and conclusions from the 2018 AM-bench measurements, challenge problems, modeling submissions, and conference. Integr Mater Manuf Innov (topical collection from the AM-bench 2018 test series)Google Scholar
- 13.Tsakalakos T et al (2006) Measurement of residual stress distributions by energy dispersive X-ray diffraction synchrotron radiation. In: The sixteenth international offshore and polar engineering conference. International Society of Offshore and Polar Engineers, San Francisco, California, USA, p. 8Google Scholar
- 15.High-density tungsten based metals—Mi-Tech metals. Available from: https://www.mttm.com/tungsten-alloys. Accessed 15 Apr 2019
- 16.Clausen B (2014) SMARTSware manual. Los Alamos National Lab, Los Alamos, NM, LA-UR 04-6581Google Scholar
- 17.Larson AC, Dreele RBV (1986) GSAS manual. Los Alamos National Lab, Los Alamos, NM, LA-UR 86-748Google Scholar
- 20.INCONEL alloy 625—special metals. Available from http://www.specialmetals.com/assets/smc/documents/alloys/inconel/inconel-alloy-625.pdf. Accessed 15 Apr 2019