journal article·2019-07-24Open access

VHCF Response up to 109 Cycles of SLM AlSi10Mg Specimens Built in a Vertical Direction

Davide S. Paolino, Andrea Tridello, Jacopo Fiocchi, Carlo A. Biffi, Giorgio Chiandussi, Massimo Rossetto, Ausonio Tuissi

Applied Sciences· Volume 9· Issue 15

Abstract

It is well-known that many manufacturing parameters affect the quasi-static and the fatigue response of additive manufacturing (AM) parts. In particular, due to the layer-by-layer production, the load orientation, with respect to the building direction, plays a fundamental role for the fatigue response. This paper investigates the fatigue response up to 109 cycles (very high cycle fatigue (VHCF)) of selective laser melting (SLM) AlSi10Mg specimens built in a vertical direction. Ultrasonic tension-compression tests (stress ratio of –1) are carried out on as-built Gaussian specimens with a large loaded volume (2300 mm3). Fracture surfaces are investigated with the scanning electron microscope to analyze the defects originating the VHCF failure. Probabilistic S-N curves are estimated and analyzed. Experimental results confirm that the defect size controls the VHCF response, thus highlighting the importance of testing large risk volumes for a reliable assessment of VHCF behavior. The average value of the VHCF strength is close to that of the hourglass specimen tested in the literature. The variability of the VHCF strength is instead significantly larger, due to the scattered size distribution of the defects located near the specimen surface, which is the most critical region for crack initiation.
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Research context

OpenAlex topics: Additive Manufacturing Materials and Processes · Additive Manufacturing and 3D Printing Technologies · Welding Techniques and Residual Stresses

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Department of Mechanical and Aerospace Engineering, Politecnico di Torino, 10129 Turin, Italy

CNR ICMATE–Institute of Condensed Matter Chemistry and Technologies for Energy, 23900 Lecco, Italy

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