PSI - Issue 77

6

Author name / Structural Integrity Procedia 00 (2025) 000 – 000

Martin Matušů et al. / Procedia Structural Integrity 77 (2026) 127 –134

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Fig. 3 a) Histogram of Fatigue Indexes FI across all tested series fitted with a Weibull distribution. The black curve represents the fitted probability density function, characterized by a shape parameter η = 1.03 and a scale parameter m = 15.68. The red dashed line marks the lower quartile at FI = 0.95), which serves as the threshold for identifying specimens with significantly lower fatigue strength compared to the overall distribution. b) K&V regression for one particular T300 series with red marks indicating specimens that exhibit lower fatigue performance according to selected criteria.

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Fig. 4 a) Layout of a representative printing platform on Concept Laser M2, where each circle denotes a specimen and color coding corresponds to different heat treatment conditions — specifically, red for NoHT and blue for T240. b) Heatmap segmentation of the build platform divided into 5×5 grid, illustrating the percentage of specimens in each zone identified as statistical outliers with significantly reduced fatigue life. Zones with the highest concentration of outliers are emphasized with bold red text. Grey regions indicate areas where fewer than five specimens were tested, and which are therefore excluded from the analysis. The printing platform (Fig. 4 a) was divided into 25 square blocks by scaling the coordinate system from 0 to 1 in both directions, corresponding to the actual platform dimensions of 250 mm × 250 mm. Each block therefore represents a physical area of 50 mm × 50 mm. Fatigue performance was analyzed within each of these blocks. However, the distribution of samples across the platform was not uniform — particularly in the corners, which are typically underutilized. Building on the findings of Kotzem [10], who investigated the influence of printing position using 30 samples distributed across the entire build platform (divided into Zone I and Zone II), our study expands this