Effect of crosshead speed and volume ratio on compressive mechanical properties of mono- and double-gyroid structures made of Inconel 718

The current development of additive technologies brings not only new possibilities but also new challenges. One of them is the use of regular cellular materials in various components and constructions so that they fully utilize the potential of porous structures and their advantages related to weight reduction and material-saving while maintaining the required safety and operational reliability of devices containing such components. It is therefore very important to know the properties of such materials and their behavior under different types of loads. The article deals with the investigation of the mechanical properties of porous structures made by the Direct Metal Laser Sintering (DMLS) of Inconel 718. Two types of basic cell topology, mono-structure Gyroid (G) and double-structure Gyroid + Gyroid (GG), with material volume ratios of 10, 15 and 20 %, were studied within our research to compare their properties under quasi-static compressive loading. The testing procedure was performed at ambient temperature with a servo-hydraulic testing machine at three different crosshead testing speeds. The recorded data were processed, while the stress–strain curves were plotted, and Young’s modulus, the yield strength Re0.2, and the stress at the first peak of the local maximum σLocMax were identified. The results showed the best behavior under compression load among the studied structures displayed by mono-structure Gyroid at 10 %. At the same time, it can be concluded that the wall thickness of the structure plays an important role in the compressive properties but on the other hand, crosshead speed doesn´t influence results significantly.Ministerstvo školstva, vedy, výskumu a športu Slovenskej republiky, (APVV-19-0550); Kultúrna a Edukacná Grantová Agentúra MŠVVaŠ SR, KEGA, (005TUKE-4/2021, 032TUKE-4/2022, SK-CN-21-0046)ELKEME S.A [APVV-19-0550, KEGA 005TUKE-4/2021, KEGA 032TUKE-4/2022

Experimental Study of the Bending Behaviour of the Neovius Porous Structure Made Additively from Aluminium Alloy

Porous materials bring components not only direct advantages in the form of lightening of constructions, saving of production materials, or improvement of physical properties, but also secondary advantages, which are manifested as a result of their daily use, e.g., in aviation and the automotive industry, which is manifested in saving fuel and, thus, environmental protection. The aim of this article is to examine the influence of the volume ratio of a complex porous structure, the so-called Neovius, on bending properties. Samples with five different relative weights of 15, 20, 25, 30, and 50% (±1%) were fabricated from AlSi10Mg aluminum alloy by Direct Laser Metal Sintering (DLMS) technology. A three-point bending test until specimen failure was performed at ambient temperature on a Zwick/Roell 1456 universal testing machine. The dependences of the bending forces on the deflection were recorded. The maximum stresses, energy absorption, and ductility indexes were calculated to compare the bending behavior of beams filled with this type of complex cellular structure. The results showed that Neovius, with a relative weight of 50%, was much more brittle compared to the other samples, while the Neovius structure, with a relative weight of 30%, appeared to be the most suitable structure for bent components among those tested. This study is a contribution not only to the development of the space and aviation industry but also to the expansion of the knowledge base in the field of material sciences. This know-how can also provide a basis for defining boundary conditions in the simulation of behavior and numerical analyses of 3D-printed lightweight components

Experimental study of the bending behaviour of the neovius porous structure made additively from aluminium alloy

Porous materials bring components not only direct advantages in the form of lightening of constructions, saving of production materials, or improvement of physical properties, but also secondary advantages, which are manifested as a result of their daily use, e.g., in aviation and the automotive industry, which is manifested in saving fuel and, thus, environmental protection. The aim of this article is to examine the influence of the volume ratio of a complex porous structure, the so-called Neovius, on bending properties. Samples with five different relative weights of 15, 20, 25, 30, and 50% (+/- 1%) were fabricated from AlSi10Mg aluminum alloy by Direct Laser Metal Sintering (DLMS) technology. A three-point bending test until specimen failure was performed at ambient temperature on a Zwick/Roell 1456 universal testing machine. The dependences of the bending forces on the deflection were recorded. The maximum stresses, energy absorption, and ductility indexes were calculated to compare the bending behavior of beams filled with this type of complex cellular structure. The results showed that Neovius, with a relative weight of 50%, was much more brittle compared to the other samples, while the Neovius structure, with a relative weight of 30%, appeared to be the most suitable structure for bent components among those tested. This study is a contribution not only to the development of the space and aviation industry but also to the expansion of the knowledge base in the field of material sciences. This know-how can also provide a basis for defining boundary conditions in the simulation of behavior and numerical analyses of 3D-printed lightweight components.Ministry of Education, MOE; Ministerstvo školstva, vedy, výskumu a športu Slovenskej republiky: APVV-19-0550; Kultúrna a Edukacná Grantová Agentúra MŠVVaŠ SR, KEGA: 005TUKE-4/2021, 032TUKE-4/2022, SK-CN-21-0046Ministry of education, science, research and sport of the Slovak Republic [APVV-19-0550, KEGA 005TUKE-4/2021]; [KEGA 032TUKE-4/2022]; [SK-CN-21-0046