Fatigue properties and material characteristics of additively manufactured AlSi10Mg – Effect of the contour parameter on the microstructure, density, residual stress, roughness and mechanical properties

Beevers, Emilie; Brandão, Ana D.; Gumpinger, Johannes; Gschweitl, Michael; Seyfert, Christoph; Hofbauer, Peter; Rohr, Thomas; Ghidini, T.

doi:10.1016/j.ijfatigue.2018.08.023

Cited by 100 publications

(51 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Many research and experimental tests have been carried out in the literature to investigate the fatigue response of AM parts, focusing mainly on the low cycle fatigue (LCF) [11] and the high cycle fatigue (HCF) response [12,13]. Regarding the HCF response, the effect of process parameters [14], heat treatments [15], defect size, and morphology [16] has been widely investigated. Moreover, there is increasing interest on the very high cycle fatigue (VHCF) behavior of AM parts, since in many structural applications the required fatigue life is significantly larger than that assessed through HCF tests.…”

Section: Introductionmentioning

confidence: 99%

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

et al. 2019

View full text Add to dashboard Cite

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 10 9 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 mm 3 ). 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.

show abstract

Section: Introductionmentioning

confidence: 99%

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

et al. 2019

View full text Add to dashboard Cite

show abstract

“…A certain amount of small defects ( Figure 6B) are hardly detected by micro-CT. Some studies have been conducted about the impact of defects on the fatigue behaviors of metal additive manufacturing parts [16][17][18]. It can be concluded that the detectability of small defects in SLM parts is more critical and demands a high resolution CT scan (highly recommend voxel size < 7 µm) or other auxiliary porosity identification methodologies.…”

Section: Characteristics Of Ebm Specimensmentioning

confidence: 99%

Micro-CT Evaluation of Defects in Ti-6Al-4V Parts Fabricated by Metal Additive Manufacturing

Gong

Nadimpalli

Rafi³

et al. 2019

Technologies

View full text Add to dashboard Cite

In this study, micro-computed tomography (CT) is utilized to detect defects of Ti-6Al-4V specimens fabricated by selective laser melting (SLM) and electron beam melting (EBM), which are two popular metal additive manufacturing methods. SLM and EBM specimens were fabricated with random defects at a specific porosity. The capability of micro-CT to evaluate inclusion defects in the SLM and EBM specimens is discussed. The porosity of EBM specimens was analyzed through image processing of CT single slices. An empirical method is also proposed to estimate the porosity of reconstructed models of the CT scan.

show abstract

“…Up to now, there is no clear explanation for such a fluctuation. As most reported residual stress measurements using XRD were performed on as-built SLM-produced samples without considering the effect of surface roughness [14,22,[28][29][30][31][32], some researchers consider the pretreatment prior to XRD measurements is necessary because the high surface roughness of the as-built samples can lead to inaccurate measurement of residual stresses [5,18]. For example, P. Mercelis et al [5] proposed electrical discharge machining (EDM) and chemical etching before XRD measurements to obtain the actual residual stresses for SLM-produced 316L stainless steel samples.…”

Section: Introductionmentioning

confidence: 99%

Strategy of Residual Stress Determination on Selective Laser Melted Al Alloy Using XRD

Chen

Sun

Li³

et al. 2020

Materials

View full text Add to dashboard Cite

Selective laser melting (SLM) is known to generate large and anisotropic residual stresses in the samples. Accurate measurement of residual stresses on SLM-produced samples is essential for understanding the residual stress build-up mechanism during SLM, while a dramatic fluctuation can be observed in the residual stress values reported in the literature. On the basis of studying the influence of surface roughness on residual stress measured using X-ray diffraction (XRD), we propose a procedure coupling XRD technique with pretreatment consisting of mechanical polishing and chemical etching. The results highlight that residual stresses measured using XRD on as-built SLM-produced samples with high surface roughness are significantly lower than those measured on samples with finished surface, which is due to the stress relaxation on the spiked surface of as-built samples. Surface distribution of residual stresses and the effect of scanning strategy were systematically investigated for SLM-produced AlSi10Mg samples. Microstructural morphology was observed at the interface between sample and building platform and was linked to the surface distribution of residual stresses. This procedure can help us accurately measure the residual stresses in SLM-produced samples and thus better understand its build-up mechanism during the SLM process.

show abstract

Fatigue properties and material characteristics of additively manufactured AlSi10Mg – Effect of the contour parameter on the microstructure, density, residual stress, roughness and mechanical properties

Cited by 100 publications

References 25 publications

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

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

Micro-CT Evaluation of Defects in Ti-6Al-4V Parts Fabricated by Metal Additive Manufacturing

Strategy of Residual Stress Determination on Selective Laser Melted Al Alloy Using XRD

Contact Info

Product

Resources

About