Parameters optimization for horizontally built circular profiles: Numerical and experimental investigation

A novel tomographic characterisation approach for sag and dross defects in metal additively manufactured channels

“…Furthermore, this approach offers potential as experimental data are normally easier to handle than complex multi-physics simulations and offer in general lower lead times. On the other hand, the experimental results from this tomographic characterisation route can possibly aid multi-physics simulations of LPBF sag and dross formation [37,38], to perform validation or tuning of the employed simulation model. In addition, the derived sag and dross characteristics could also be a useful instrument to further refine LPBF design guidelines, e.g.…”

“…Other investigations on developed residual stresses during LPBF [13] production could in theory as well be used to derive similar a-priori compensations. In relation to sag and dross compensation, without the aforementioned teardrop or complete redesign of the channel geometry, only Khan et al [37] and Solyaev et al [38] specifically investigated the necessary shape-compensation for these critical defects of the overhanging channel surface. Both researches used numerical simplified models to study the development of the defects; however, Khan et al preferred to only tune the down-skin LPBF processing parameters, whereas Solyaev et al suggested combining tuning of both parameters and an overcompensated channel geometry to obtain a close-to-nominal channel geometry.…”

“…An advanced method is needed for complete geometrical characterization of peak deviations and position of the dross and for modelling of its form depending on build orientation and overhang angle as well as separation of the straightening effect from sag and dross, to better understand how the protrusions develop inside LPBF channels and bores. The experimental knowledge gained by such characterization could then be combined with simplified models, as the ones envisioned in [37,38], both to validate them and to increase their accuracy. If a quick methodology is made available to analyse all deviations (including straightening as well as sag and dross) induced by LPBF fabrication, a-priori channel compensations based on experimental data could be applied industrially.…”

Estimation of the compression strength and surface roughness of the as-built SLS components using weibull distribution

“…The SLS process is quite useful in producing complex structures with superior mechanical and microstructural properties that are otherwise difficult to create using conventional techniques due to process limitations. It is because the SLS process enables the sintering of powder particles at a target location of a few hundred mi-crometers to generate a complex profile, which is difficult to create using conventional techniques [2][3][4][5].…”

Weibull distribution of selective laser melted AlSi10Mg parts for compression testing

“…The mechanical properties of SLM components are either superior or comparable to conventional structures [1,5]. However, high surface roughness, sub-surface porosity, high residu-al stress, and non-equilibrium microstructure can produce unwanted mechanical properties in SLM components that may limit their wide commercial acceptance [6][7][8]. These unacceptable mechanical effects are the results of process uncertainties.…”