# Design of Selective Laser Melting (SLM) Structures: Consideration of Different Material Properties in Multiple Surface Layers Resulting from the Manufacturing in a Topology Optimization

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## Abstract

**:**

## 1. Introduction

## 2. Methodology

## 3. Model Design

## 4. Results and Discussion

## 5. Conclusions and Outlook

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## References

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**Figure 1.**Exemplary representation (cut through x–y plane) of the three porous areas (

**left**) and CT scan to visualize the porosity distribution in one print layer (

**right**) adapted from [17].

**Figure 3.**Surface meshes of the interim result (

**top**) as well as offset 1 (

**center**) and offset 2 (

**bottom**).

**Figure 4.**Surface meshes (

**top**) as well as meshed areas including assigned material properties of the interim result (

**bottom**).

**Figure 5.**Porous areas including assigned material properties of the interim result considering the print direction (

**top**) and material properties transferred to the initial topology optimization mesh (

**bottom**).

**Figure 7.**Result of the developed optimization method: overall design (

**left**) and sectional view (

**right**).

**Figure 8.**Result of the standard topology optimization: overall design (

**left**) and sectional view (

**right**).

**Figure 9.**Comparison of the optimization history of the standard topology optimization and the developed optimization method.

**Figure 10.**Resulting design of the developed optimization method including porous areas (

**left**) and result of the static FE analysis (

**right**).

**Figure 11.**Resulting design of the standard topology optimization including porous areas (

**left**) and result of the static FE analysis (

**right**).

**Figure 12.**Section in the layer plane through the design from the developed optimization method: front view (

**top**) and plan view (

**bottom**).

Laser Power | Scanning Speed | Hatching Distance | Layer Thickness |
---|---|---|---|

250 W | 900 mm/s | 150 µm | 30 µm |

Contour Area | Interface Area | Hatching Area | |
---|---|---|---|

Young’s modulus [GPa] | 75 | 65.5 | 72.5 |

Poisson’s ratio [–] | 0.35 | 0.35 | 0.35 |

Thickness [mm] | 0.4 | 0.1 | - |

Developed Optimization Method | Standard Topology Optimization | |
---|---|---|

Final volume [%] | 65.83 | 65.69 |

Strain energy [mJ] | 350.247 | 348.598 |

Required iterations [–] | 39 | 37 |

Contour/Interface/Hatching area [%] | 37.77/7.68/54.55 | 30.86/7.58/61.56 |

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**MDPI and ACS Style**

Holoch, J.; Lenhardt, S.; Revfi, S.; Albers, A.
Design of Selective Laser Melting (SLM) Structures: Consideration of Different Material Properties in Multiple Surface Layers Resulting from the Manufacturing in a Topology Optimization. *Algorithms* **2022**, *15*, 99.
https://doi.org/10.3390/a15030099

**AMA Style**

Holoch J, Lenhardt S, Revfi S, Albers A.
Design of Selective Laser Melting (SLM) Structures: Consideration of Different Material Properties in Multiple Surface Layers Resulting from the Manufacturing in a Topology Optimization. *Algorithms*. 2022; 15(3):99.
https://doi.org/10.3390/a15030099

**Chicago/Turabian Style**

Holoch, Jan, Sven Lenhardt, Sven Revfi, and Albert Albers.
2022. "Design of Selective Laser Melting (SLM) Structures: Consideration of Different Material Properties in Multiple Surface Layers Resulting from the Manufacturing in a Topology Optimization" *Algorithms* 15, no. 3: 99.
https://doi.org/10.3390/a15030099