Properties Of Lattice Structures Research Articles

Deep learning-enabled design for tailored mechanical properties of SLM-manufactured metallic lattice structures

The lattice structures obtained by combining repetitive light cellular forms provide superior high strength to weight capabilities compared to monolithic solid bodies. These properties of lattice structures can be further enhanced by improving the design and manufacturing process. However, the process of creating aluminum alloy lattice structures with tailored mechanical properties is still challenging due to the wide range of possible designs and their complex structure-property relationships. This paper proposes a new methodology that uses the deep learning-based 3D Generative Adversarial Network (3DGAN) model to solve this complex engineering problem. Unlike previous studies on deep learning-based lattice design, the dataset obtained through parametric design and Simulated Annealing techniques enables GAN to create new 3D lattice structures with improved mechanical strength properties. The designs generated with the GAN algorithm were produced using Selective Laser Melting Additive Manufacturing (SLM-AM) technology. The mechanical properties of SLM-fabricated (SLMed) AlSi10Mg unit cell samples were examined by a series of compression and impact tests. The results reveal that the lattice configurations generated using the generative model exhibit improved mechanical properties (e.g., a remarkable increase in normalized energy absorption and extension capacities of up to 57% and 26%, respectively). This study shows that designs generated with the 3DGAN model in lattice structures improve the design space by improving their mechanical properties. Moreover, the successful integration of deep learning and SLM-AM opens up new possibilities for creating custom parts with improved strength-to-weight ratios, dimensional accuracy, and mechanical performance.

Novel femur-like multimodal ultrahigh strength structure with superb freedom based on the improvement strategy of curvature fabricated by additive manufacturing

Based on the microstructure of biological femur, the femur-like multimodal surface structures are designed. But they exhibit fracture behavior when the porosity changes, resulting in structural failure. The high curvature surface factor is introduced to improve the fracture behavior of the biomimetic surface structure. Combine the high curvature surface factor to construct novel biomimetic homogenized surface structures. Novel radial gradient surface structures and axial gradient surface structures are designed based on the construction concept of cone functions and linear functions gradients. Theoretical, experimental and numerical methods are used to investigate the mechanical properties of novel biomimetic multimodal surface structures. Euler theory states that the properties of lattice structures are determined by the relative density of structures. The load distribution in the radially gradient structure is uniform, and the deformation mode presents overall failure, which can achieve better resistance and dissipation of the load. The deformation modes of axial gradient structures present layered failure. The underlying mechanism of the difference in mechanical properties of biomimetic multimodal structures is explained in detail. It’s very important significance for targeted application in protective engineering.

Observed geometrical imperfection and the mechanical properties of lattice structures produced by powder bed fusion (PBF) process

Observed geometrical imperfection and the mechanical properties of lattice structures produced by powder bed fusion (PBF) process

Effect of Architected Structural Members on the Viscoelastic Response of 3D Printed Simple Cubic Lattice Structures.

Three-dimensional printed polymeric lattice structures have recently gained interests in several engineering applications owing to their excellent properties such as low-density, energy absorption, strength-to-weight ratio, and damping performance. Three-dimensional (3D) lattice structure properties are governed by the topology of the microstructure and the base material that can be tailored to meet the application requirement. In this study, the effect of architected structural member geometry and base material on the viscoelastic response of 3D printed lattice structure has been investigated. The simple cubic lattice structures based on plate-, truss-, and shell-type structural members were used to describe the topology of the cellular solid. The proposed lattice structures were fabricated with two materials, i.e., PLA and ABS using the material extrusion (MEX) process. The quasi-static compression response of lattice structures was investigated, and mechanical properties were obtained. Then, the creep, relaxation and cyclic viscoelastic response of the lattice structure were characterized. Both material and topologies were observed to affect the mechanical properties and time-dependent behavior of lattice structure. Plate-based lattices were found to possess highest stiffness, while the highest viscoelastic behavior belongs to shell-based lattices. Among the studied lattice structures, we found that the plate-lattice is the best candidate to use as a creep-resistant LS and shell-based lattice is ideal for damping applications under quasi-static loading conditions. The proposed analysis approach is a step forward toward understanding the viscoelastic tolerance design of lattice structures.

Effect of atomic tessellations on structural and functional properties of additive manufactured lattice structures

The properties of lattice structure are influenced by cell morphology, cell size, relative density and tessellations. In this study, the concept of tessellation has been evaluated for structural and functional properties of additively manufactured lattice structures using PA-12 material. The tessellation design of unit lattice cell is inspired by arrangement of atoms in crystal structures. The strategy of mimicking these different arrangements at atomic level to generate mesoscale cellular structures is termed as ‘Atomic Tessellation’. In the current study, arrangement of metallic crystal structures: BCC, FCC and HCP were compared with conventional periodically tessellated SC structure using sea-urchin unit cell for mechanical, energy absorption and structural behaviour properties. The tessellated lattice structures were printed with hybrid AM technology using HP-MJF 4200. The significant effect of tessellations was observed during compression testing of printed samples in terms of their stress-strain behaviour. Lattice structures such as SC, BCC, FCC and HCP_90 shows ‘degradation-prone deformation behaviour’ which is similar to stretch dominated behaviour in structural elements (thin struts and thin walls). On the other hand, HCP tessellation (HCP_0) converts ‘degradation-prone deformation behaviour’ into ‘progressive deformation behaviour’ that is similar to bending dominated behaviour in structural elements. Moreover, significant effects of tessellations were also observed in load bearing and energy absorption properties. Although the study has attempted to introduce the design concept of atomic tessellations from structural point of view, further studies are required to strengthen tessellation based design principles for obtaining different structural and functional properties. • The novel concept of ‘Atomic Tessellation’ have been introduced in design of cellular lattice structures. • Metallic crystal structures: SC, BCC, FCC and HCP were designed in mesoscale using Sea Urchin (SU) inspired unit cell. • Mechanical properties and energy absorption capacity was affected by tessellation strategy. • Tessellation strategy converts stretch-dominated behavior of lattice structure to bending dominated behavior and vice versa. • HCP tessellated structure behaves as bending dominated in 0˚orientation whereas as stretch dominated behavior was observed in 90˚orientation.

Evaluation of the dynamic response of triply periodic minimal surfaces subjected to high strain-rate compression

Architected cellular structures based on triply periodic minimal surfaces (TPMS) have attracted significant attention due to their lightweight, superior, and controllable mechanical properties. Such lattice structures can be potential candidates for high specific energy absorption (SEA) applications. In this study, five TPMS sheet-based structures (Gyroid, Primitive, IWP, Diamond and Fisher-Koch) were designed, fabricated, and tested under quasi­-static and dynamic loading conditions. Laser powder bed fusion (L-PBF) is employed to facilitate the fabrication of these complex structures using stainless steel (SS316L) at three different relative densities. Scanning electron microscopy (SEM) and micro­ Computed Tomography (micro­CT) were utilized to assess the quality of the printed structures. The dynamic compressive behavior is investigated by conducting direct impact compression tests utilizing a Direct Impact Hopkinson Bar (DIHB) at a strain-rate of 2057 s −1 . Quasi-­static tests are also performed at a strain-rate of 0.005 s −1 . The quasi-static and dynamic mechanical responses are then compared to explore the changes in plateau stress and specific energy absorption values of the five TPMS lattices in these two loading regimes. Furthermore, the effects of changing both architecture and relative density on the properties of lattice structures are investigated. The results show that all five topologies exhibit an enhanced mechanical performance under dynamic loading. In fact, Diamond structure demonstrates the highest SEA value of 35.57 J/g under the high strain-rate loading condition, in comparison to 30.85 J/g in the quasi-static loading. This study suggests that TPMS structures could be potential candidates not only for quasi­-static, but also for dynamic applications related to a high strain-rate loading. • Five TPMS lattices are designed and manufactured using Laser Powder Bed Fusion (LPBF). • Evaluation of the dynamic mechanical performance of lattices based on triply periodic minimal surfaces. • TPMS lattices exhibit enhanced plateau stress and specific energy absorption in high strain-rate loading conditions.

Estimation of Mechanical Properties of Lattice Structures Produced by Powder Bed Method

Estimation of Mechanical Properties of Lattice Structures Produced by Powder Bed Method

Compressive Strength Prediction of Quad-Diametral Lattice Structures

Additive manufacturing is rapidly developing technology in all areas of industry. It is reducing the delivering time of each prototype from the manufacturer to the final user. This paper deals with mechanical properties of lattice structures. They are produced by additive technologies from the plastic material. Lattice structures are special space-filling unit cells, which can fill gaps in parts. They have good ratio between overall weight and strength. Nowadays are these structures commonly used, but their mechanical properties are not well described. This makes the design process difficult. Mechanical compressive test and virtual evaluation by the finite element method was performed. It was done for three different Quad-Diametral structures (Quad-Diametral, Quad-Diametral-Line and Quad-Diametral-Cross). Results from both testing approaches (real measurement and finite element method) are deeply described in this paper. It was shown, that the Quad-Diametral-Cross lattice cell has higher mechanical properties comparing to others. Increasing of the stiffness was 121% only with weight higher by 43%. The plastic material Ultimaker PLA (polyactic acid) was used as reference material in this research.

Evaluation of Static and Fatigue Properties of Regular Lattice and Trabecular Cellular Structures

Laser-based Powder Based Fusion (LPBF) being one of the most widely used additive manufacturing (AM) process has not only impacted the design of components in aeronautical and automobile industries but also in development of porous components. The properties of these lattice structures can be tailored according to the structural and compatibility requirements depending on the application. Therefore, understanding the behavior of cellular structures under static and fatigue loading becomes necessary. The factors that influence their behavior include relative density, cell topology, cell geometry and microstructure of the material.In this current study, titanium alloy Ti6Al4V cellular structures with four different geometries (Cubic, Star-shaped, X-shaped and Trabecular) manufactured using LPBF are considered. The mechanical performances of the samples, designed in order to have an overall porosity of 70-75%, have been evaluated with static tests under tensile and compressive loading, and with compression-compression fatigue test (R=0.1). The results indicate a clear decrease in the mechanical properties with increase in the bending dominated behavior of the cell types. However, Cubic structures displayed a catastrophic fracture behaviour, while the other structures were more resilient. Furthermore, despite the facts being bending dominated and with the lowest number of struts per node, the Trabecular structures showed good fatigue resistance thanks to the presence of struts in all the directions.

Моделирование механических свойств ячеистых структур, изготовленных селективным лазерным плавлением

Моделирование механических свойств ячеистых структур, изготовленных селективным лазерным плавлением

Evolution of the Lattice Structures Properties Manufactured by Selective Laser Melting and Subsequent Hot Isostatic Pressing

Geometric features of mesh structures allow them to be used as a material for medical purposes. In this paper, the study of the properties of lattice structures, performed by selective laser melting was carried out. The range of high accuracy of manufactured samples and microstructure was determinated. The results of changes in porosity and mechanical properties after hot isostatic pressing in comparison with cortical bone and heat treated material and microstructure of samples are represented.

Evaluation of Vibration and Acoustic Properties of Lattice Structure Manufactured by Selective Laser Melting

Evaluation of Vibration and Acoustic Properties of Lattice Structure Manufactured by Selective Laser Melting

Evaluation of the Fluid Properties of Lattice Structures for Cooling Channel

Evaluation of the Fluid Properties of Lattice Structures for Cooling Channel

206 マイクロラティス構造の機械特性に及ぼす形状不均一性の影響

206 マイクロラティス構造の機械特性に及ぼす形状不均一性の影響

圧縮荷重を受ける軽量Lattice構造の機械特性の評価 : 第3報,端部の拘束による機械特性への影響

圧縮荷重を受ける軽量Lattice構造の機械特性の評価 : 第3報,端部の拘束による機械特性への影響

ELNES study of chemical solution deposited [formula omitted] Ruddlesden–Popper films: Experiment and simulation

This article analyzes electron energy-loss near-edge fine structures of the SrO(SrTiO3)n=1 Ruddlesden–Popper system and of the parent compounds SrTiO3 and SrO by comparison with first principles calculations. For that, the fine structures of chemical solution deposited Ruddlesden–Popper films have been experimentally recorded by means of transmission electron microscopy. Moreover, density of states computations using an all-electron density-functional code have been performed. It is shown that the appearance and shape of the experimental O–K and Ti–L2,3 fine structure features result from the crystallography-dependent electronic structure of the investigated oxides, which display technologically interesting dielectric as well as lattice–structural properties.

圧縮荷重を受ける軽量Lattice構造の機械特性の評価 : 第2報,圧縮負荷方向の違いおよび不完全セルの存在による機械特性への影響

圧縮荷重を受ける軽量Lattice構造の機械特性の評価 : 第2報,圧縮負荷方向の違いおよび不完全セルの存在による機械特性への影響

The dual Heyting arrow lattice for biologic relational processes

Qualitative relations in biological systems were studied by means of lattices. The first main representations gave place to lattices being double pseudo-Boolean algebras. So, close to the poset which defined the lattices, two operations appeared: the Heyting arrow and the dual Heyting arrow. Both are important to relate noncomparable elements in terms of processes concerned with increasing and decreasing energies in the system, as results from the order defining the poset which considers the lattice elements as relational energetic states. The present developments find out mathematical properties of lattice structures satisfying dual Heyting arrow operations between noncomparable elements.