Influence of Laser Polishing on the Material Properties of Aluminium L-PBF Components

Hofele, Markus; Roth, A.; Hegele, Patrick; Schubert, Tim; Schanz, Jochen; Harrison, David K.; Silva, A.K.M. De; Riegel, Harald

doi:10.3390/met12050750

Cited by 7 publications

(1 citation statement)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For the evaluation of the measurement results, the sin 2

method was applied relying on the diffraction elastic constants

GPa and

[ 22 ]. The

peak positions used for this method were determined by fitting pseudo-Voigt functions separately to the

and

components of the recordings [ 23 ].…”

Section: Experimental Investigationsmentioning

confidence: 99%

Residual Stresses in Ribbed Reinforcing Bars

Robl,

Hegele,

Krempaszky

et al. 2023

Materials

Self Cite

View full text Add to dashboard Cite

Ribbed reinforcing bars (rebars) are used for the reinforcement of concrete structures. In service, they are often subjected to cyclic loading. In general, the fatigue performance of rebars may be influenced by residual stresses originating from the manufacturing process. Knowledge about residual stresses in rebars and their origin, however, is sparse. So far, residual stress measurements are limited to individual stress components, viz., to the non-ribbed part of the rebar surface. At critical points of the rebar surface, where most of the fatigue cracks originate, i.e., the foot radius regions of transverse ribs, the residual stress state has not yet been investigated experimentally. To extend the knowledge about residual stresses in rebars within the scope of this work, residual stress measurements were carried out on a rebar specimen with a diameter of 28 mm made out of the rebar steel grade B500B. In addition, numerical simulations of the TempCoreTM process were carried out. The results of the experimental investigations show tensile residual stresses in the core and the transition zone of the examined rebar specimen. Low compressive residual stresses are measured at the non-ribbed part of the rebar surface, while high compressive residual stresses are present at the tip of the transverse ribs. The results of the numerical investigations are in reasonable accordance with the experimental results. Furthermore, the numerical results indicate moderate tensile stresses occurring on the rebar surface in the rib foot radius regions of the transverse ribs. High stress gradients directly beneath the rebar surface, which are reported in the literature and which are most likely related to a thin decarburized surface layer, could be reproduced qualitatively with the numerical model developed.

show abstract

“…For the evaluation of the measurement results, the sin 2

method was applied relying on the diffraction elastic constants

GPa and

[ 22 ]. The

peak positions used for this method were determined by fitting pseudo-Voigt functions separately to the

and

components of the recordings [ 23 ].…”

Section: Experimental Investigationsmentioning

confidence: 99%

Residual Stresses in Ribbed Reinforcing Bars

Robl,

Hegele,

Krempaszky

et al. 2023

Materials

Self Cite

View full text Add to dashboard Cite

show abstract

Laser‐Based Closed‐Loop Controlled Heat Treatment for Residual Stress Relief of Additively Manufactured AlSi10Mg Components

Wenger,

Hegele,

Hofele

et al. 2024

Adv Eng Mater

View full text Add to dashboard Cite

In laser powder bed fusion of metals small melt pools with extremely short solidification times and steep temperature gradients to the surrounding material exist due to the layer‐wise and selective melting process with small areas of energy input compared to the cooler, solid ambient material. This causes high thermally induced residual stresses (RS), which can lead to the immediate rejection of the component due to critical part deformation and inhomogeneous mechanical properties under load. To prevent this, furnace‐based stress relief heat treatments are commonly applied before cutting‐off the part from the built platform. In this study a novel closed‐loop controlled laser‐based heat treatment using temperature feedback through inline pyrometer measurement is investigated, enabling a fast and highly efficient postprocess stress relief. Therefore, a laser beam is guided by a scanner optics in a meandering pattern over the top surface of AlSi10Mg cantilever specimens. It enables a decrease of near‐surface RS from 158 to 5 N mm−2, resulting in a reduction of displacement by over 90% at material affecting depths up to 3 mm and area rates of 8 to 163 mm2 s−1.

show abstract