Localised high temperature gradient
Cooling phase and shrinking
Limiting residual stresses during SLM
A few factors influence the amount of residual stresses locked in the material:
- Number of layers (build height and size)
- Base plate geometry and thickness
- Materials properties
- Influence of the exposure strategy and influence of the sector scanning order
- Parts connected to the base plate contain very high stress levels (in the range of the material’s yield strength).
- Parts removed from the base plate contain much lower stress levels but suffer from deformation during part removal.
- Residual stresses magnitude depends on the part height and the stiffness and height of the base plate.
- The exposure strategy has a large influence on the residual stress levels being developed. Islands or chessboard patter scans result in a lower maximum stress value.
- Heating the substrate plate reduces the stress level since temperature gradients are reduced.
- Stress-relief post heat treatment (more on that later) can be used before removing components from the build substrate.
 Peter Mercelis and Jean-Pierre Kruth, Residual stresses in selective laser sintering and selective laser melting, Rapid Prototyping Journal, Volume 12 · Number 5 · 2006 · 254–265
 L. Parry, I. Ashcroft, D. Bracket, R. D. Wildman, Investigation of Residual Stresses in Selective Laser Melting, Key Engineering Materials Vol. 627 (2015) pp 129-132