Residual stress evaluation of components produced via direct metal laser sintering

• Published in: Welding in the world Vol. 62; no. 3; pp. 663 - 674
• Main Authors: Kemerling, Brandon, Lippold, John C., Fancher, Chris M., Bunn, Jeffrey
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-05-2018; Springer Nature B.V; Springer Nature
• Subjects: Additive manufacturing; Chemistry and Materials Science; Compressive properties; Construction; Direct metal laser sintering; Energy consumption; Finite element method; Heating; Laser sintering; MATERIALS SCIENCE; Metal powders; Metallic Materials; Neutron diffraction; Process parameters; Process variables; Production methods; Rapid prototyping; Research Paper; Residual stress; Solid Mechanics; SYSWELD; Theoretical and Applied Mechanics; Additive manufacturing; Direct metal laser sintering; Neutron diffraction; SYSWELD; Residual stress
• ISSN: 0043-2288; 1878-6669
• DOI: 10.1007/s40194-018-0572-z

Direct metal laser sintering is an additive manufacturing process which is capable of fabricating three-dimensional components using a laser energy source and metal powder particles. Despite the numerous benefits offered by this technology, the process maturity is low with respect to traditional subtractive manufacturing methods. Relationships between key processing parameters and final part properties are generally lacking and require further development. In this study, residual stresses were evaluated as a function of key process variables. The variables evaluated included laser scan strategy and build plate preheat temperature. Residual stresses were measured experimentally via neutron diffraction and computationally via finite element analysis. Good agreement was shown between the experimental and computational results. Results showed variations in the residual stress profile as a function of laser scan strategy. Compressive stresses were dominant along the build height (
z
) direction, and tensile stresses were dominant in the
x
and
y
directions. Build plate preheating was shown to be an effective method for alleviating residual stress due to the reduction in thermal gradient.