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Materials and Hydrogen Isotope Science at Sandia's California Laboratory

Zimmerman, Jonathan A.; Balch, Dorian K.; Bartelt, Norman C.; Buchenauer, D.A.; Catarineu, Noelle R.; Cowgill, D.F.; El Gabaly Marquez, Farid E.; Karnesky, Richard A.; Kolasinski, Robert K.; Medlin, Douglas L.; Robinson, David R.; Ronevich, Joseph A.; Sabisch, Julian E.; San Marchi, Christopher W.; Sills, Ryan B.; Smith, Thale R.; Sugar, Joshua D.; Zhou, Xiaowang Z.

Abstract not provided.

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TYPE Conference Poster YEAR 2018
OSTI

A thermal-mechanical finite element workflow for directed energy deposition additive manufacturing process modeling

Additive Manufacturing

Stender, Michael S.; Beghini, Lauren L.; Sugar, Joshua D.; Veilleux, Michael V.; Subia, Samuel R.; Smith, Thale R.; San Marchi, Christopher W.; Brown, Arthur B.; Dagel, Daryl D.

This work proposes a finite element (FE) analysis workflow to simulate directed energy deposition (DED) additive manufacturing at a macroscopic length scale (i.e. part length scale) and to predict thermal conditions during manufacturing, as well as distortions, strength and residual stresses at the completion of manufacturing. The proposed analysis method incorporates a multi-step FE workflow to elucidate the thermal and mechanical responses in laser engineered net shaping (LENS) manufacturing. For each time step, a thermal element activation scheme captures the material deposition process. Then, activated elements and their associated geometry are analyzed first thermally for heat flow due to radiation, convection, and conduction, and then mechanically for the resulting stresses, displacements, and material property evolution. Simulations agree with experimentally measured in situ thermal measurements for simple cylindrical build geometries, as well as general trends of local hardness distribution and plastic strain accumulation (represented by relative distribution of geometrically necessary dislocations).

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TYPE Journal Article YEAR 2018
ScopusOSTIDOI

Anomalous Annealing Response of Directed Energy Deposited Type 304L Austenitic Stainless Steel

JOM

Smith, Thale R.; Sugar, Joshua D.; Schoenung, Julie M.; San Marchi, Christopher W.

Directed energy deposited (DED) and forged austenitic stainless steels possess dissimilar microstructures but can exhibit similar mechanical properties. In this study, annealing was used to evolve the microstructure of both conventional wrought and DED type 304L austenitic stainless steels, and significant differences were observed. In particular, the density of geometrically necessary dislocations and hardness were used to probe the evolution of the microstructure and properties. Forged type 304L exhibited the expected decrease in measured dislocation density and hardness as a function of annealing temperature. The more complex microstructure–property relationship observed in the DED type 304L material is attributed to compositional heterogeneities in the solidification microstructure.

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TYPE Journal Article YEAR 2018
ScopusOSTIDOI
Results 101–125 of 328
Results 101–125 of 328