TY  - JOUR
A1  - Mishurova, Tatiana
A1  - Cabeza, Sandra
A1  - Thiede, Tobias
A1  - Nadammal, Naresh
A1  - Kromm, Arne
A1  - Klaus, Manuela
A1  - Genzel, Christoph
A1  - Haberland, Christoph
A1  - Bruno, Giovanni
T1  - The Influence of the Support Structure on Residual Stress and Distortion in SLM Inconel 718 Parts
JF  - Metallurgical and Materials Transactions A
N2  - The effect of support structure and of removal from the base plate on the residual stress state in selective laser melted IN718 parts was studied by means of synchrotron X-ray diffraction. The residual stresses in subsurface region of two elongated prisms in as-built condition and after removal from the base plate were determined. One sample was directly built on a base plate and another one on a support structure. Also, the distortion on the top surface due to stress release was measured by contact profilometry. High tensile residual stress values were found, with pronounced stress gradient along the hatching direction. In the sample on support, stress redistribution took place after removal from the base plate, as opposed to simple stress relaxation for the sample without support. The sample on support structure showed larger distortion compared to sample without support. We conclude that the use of a support decreases stress values but stress-relieving heat treatments are still needed.
Y1  - 2018
U6  - https://doi.org/10.1007/s11661-018-4653-9
SN  - 1073-5623
SN  - 1543-1940
VL  - 49A
IS  - 7
SP  - 3038
EP  - 3046
PB  - Springer
CY  - New York
ER  - 
TY  - JOUR
A1  - Thiede, Tobias
A1  - Cabeza, Sandra
A1  - Mishurova, Tatiana
A1  - Nadammal, Naresh
A1  - Kromm, Arne
A1  - Bode, Johannes
A1  - Haberland, Christoph
A1  - Bruno, Giovanni
T1  - Residual Stress in Selective Laser Melted Inconel 718
BT  - Influence of the Removal from Base Plate and Deposition Hatch Length
JF  - Materials performance and characterization
N2  - The residual stress distribution in IN718 elongated prisms produced by selective laser melting was studied by means of neutron (bulk) and laboratory X-ray (surface) diffraction. Two deposition hatch lengths were considered. A horizontal plane near the top surface (perpendicular to the building direction) and a vertical plane near the lateral surface (parallel to the building direction) were investigated. Samples both in as-built (AB) condition and removed from the base plate (RE) were characterized. While surface stress fields seem constant for the AB condition, X-ray diffraction shows stress gradients along the hatch direction in the RE condition. The stress profiles correlate with the distortion maps obtained by tactile probe measurements. Neutron diffraction shows bulk stress gradients for all principal components along the main sample directions. We correlate the observed stress patterns with the hatch length, i.e., with its effect on temperature gradients and heat flow. The bulk stress gradients partially disappear after removal from the base plate.
KW  - residual stress
KW  - IN718
KW  - neutron diffraction
KW  - laboratory x-ray diffraction
KW  - additive manufacturing
KW  - selective laser melting
KW  - coordinate measurement machine
Y1  - 2018
U6  - https://doi.org/10.1520/MPC20170119
SN  - 2379-1365
SN  - 2165-3992
VL  - 7
IS  - 4
SP  - 717
EP  - 735
PB  - American Society for Testing and Materials
CY  - West Conshohocken
ER  -