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This study proposes 3D-printed Poly L-lactic acid (PLA) scaffolds coated with alginate/MgO, and includes three different cellular topologies. Three unique scaffold models were considered: Perovskite type 1 (P1), Perovskite type 2 (P2), and IWP. Each scaffold was coated with alginate/MgO at the concentrations of 0 wt%, 5 wt%, 10 wt%, 15 wt%, and 20 wt%. For morphological and phase study, the microstructure of fabricated scaffolds was characterized using a Field Emission Scanning Electron Microscope (FESEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD) analysis. Besides, the biological characteristics of scaffolds, such as biocompatibility, antibacterial activity, and cell survival were studied after 21 days of soaking in the simulated body fluid (SBF). The results of biological studies indicate that the apatite layer covered the majority of composite scaffold's surface and sealed the pores' surface. The material properties of Alginate/MgO RVEs were evaluated under PBC, and it described that the elastic modulus enhanced from 100 (pure Alginate) to 130 MPA by adding 20 wt% MgO nanoparticles. The presented findings were compared to the results obtained by the experimental procedure and revealed satisfactory agreement. RVE-achieved material properties were used in the additional studies on the scaffolds to find the best candidate due to the material properties and architectures. Furthermore, experiment and finite element simulation were used to evaluate the mechanical properties of scaffolds under the compressive deformation. According to the results, the compressive strength of structures follows the order σ

Multi-layer metallic sheets are composed of two or more metallic layers connected to each other to achieve desirable features based on the various properties of the constituent layers. This study attempted to predict the forming limits and deformation behavior of three-layer metallic sheets. Additionally, the effects of the layer arrangement on the forming limit diagram (FLD), stress triaxiality, and limiting dome height (LDH) were investigated using a finite element numerical approach. To this end, three-layer metallic sheets made of aluminum (AA3004), stainless steel (SUS304), and copper (Cu1011) bonded by polyurethane as the bonding layer were employed. The numerical results were validated using the experimental results of Nakajima stretch-forming tests. The numerical results were in good agreement with the experimental data. The results indicate that the formability of the three-layer sheet increased by placing the AA3105 layer as the inner layer in contact with the punch, the Cu1011 layer in the middle, and the SUS304 layer as the outer layer. Therefore, the formability of the Al-Cu-SUS sheet was higher than that of the other layer arrangements. Moreover, the results show that the material properties, particularly the tensile strength, play a key role in controlling the FLD of the three-layer sheets.