PSI - Issue 77

Martin Matušů et al. / Procedia Structural Integrity 77 (2026) 127 –134 Author name / Structural Integrity Procedia 00 (2025) 000 – 000

128

2

1. Introduction Additive manufacturing (AM) technologies, particularly Laser Powder Bed Fusion (L-PBF), have enabled the production of complex, lightweight metallic components with good mechanical properties. Among L-PBF-compatible alloys, AlSi10Mg is widely used in aerospace and automotive industries due to its good strength-to-weight ratio, corrosion resistance, and printability. However, fatigue behaviour of final products remains a key limiting factor for critical applications, while the performance variability introduced by more complicated localized processing conditions, especially the printing position on the build plate, is not yet fully understood. This study investigates the fatigue performance of additively manufactured AlSi10Mg components produced using Laser Powder Bed Fusion (L-PBF) on a Concept Laser M2 system. The primary focus is on high-cycle fatigue (HCF) behaviour and how it is influenced by various processes and material parameters, most notably, the position of the specimen on the build platform. Additional factors considered include specimen geometry [1], heat treatment [2], or number of levels of powder degradation [3]. The comprehensive experimental campaign encompasses seven printing platforms. It yields a dataset of 22 distinct fatigue curves, each showing unique fatigue responses. While Del Re et al. [4] suggested that build position has minimal impact on mechanical properties, this aspect remains underexplored in current literature. Notably, Matušů et al. [5] previously reported that specimen placement along the direction of the inert gas flow can affect fatigue life. To the authors’ knowledge, no existing studies have specifically examined the relationship between build position and fatigue life for AlSi10Mg under systematically varied thermal and geometric conditions. Yet, position-dependent parameters such as surface roughness [6] and laser beam angle [7] could potentially explain performance variation across the platform. Understanding the influence of building position on fatigue life is crucial for improving reliability in structural applications of additively manufactured components. This study aims to address this knowledge gap by offering a detailed, data-driven assessment of how spatial variation across the build plate affects fatigue strength. Through this analysis, the study contributes to the development of more robust design and manufacturing strategies for critical AM components.

Nomenclature A – H

8 individual cases of specimen designs

BP

Building platform in the Concept Laser M2 3D printer Parameters of the Kohout- Věchet regression [8]

a KV , C, B, β

Applied stress amplitude [MPa]

σₐ FI

Fatigue Index relating the actual fatigue strength with the strength from K&V regression 25 th percentile threshold of FI based on Weibull CDF Cumulative distribution function (CDF) of the scaled stress amplitude

FI 25% F ( FI )

Scale parameter of the Weibull distribution

η

L-PBF

Laser Powder Bed Fusion (additive manufacturing process)

Shape parameter of the Weibull distribution

m N f

Number of cycles to failure

NoHT

No heat treatment applied; specimens tested in as-built condition Probability of failure indicated with percentage written in the index

P 50%

Load ratio ( R = minimum load / maximum load), used to define test loading conditions

R

Run-out

Specimen that survived 10⁷ cycles without failure

Applied stress amplitude [MPa]

σₐ

σₐ ( P 50% )

Stress amplitude corresponding to a 50% probability of failure, based on the K&V model Heat treatment (HT) cases with the number referring to HT temperatures in °C

T200 / T240 / T300