Fracture toughness anisotropy is a key concern in IN718 components produced by Laser Powder Bed Fusion (LPBF), due to their strong crystallographic texture and characteristic lamellar microstructure. In this study, the effect of grain orientation on fracture toughness was evaluated by testing two LPBF IN718 builds with the same laser scanning strategy (R0), but with two different orientations: vertical (R0-0) and 45° inclined (R0-45) relative to the build direction. The mechanical response was assessed through compact tension (CT) tests following ASTM E399 and ASTM E1820 standards. Results show that the R0-45 specimens exhibited a fracture toughness nearly 2.5 times higher than R0-0 specimens. Detailed microstructural analysis, supported by EBSD and SEM, reveals that the higher toughness in the R0-45 orientation is linked to a combination of smaller effective grain size along the crack path, higher levels of geometrically necessary dislocations (GND), and increased kernel average misorientation (KAM), which collectively enhance plastic accommodation and crack-tip shielding. These findings support and reinforce the established understanding of the relationship between microstructure and anisotropic fracture behavior in LPBF IN718, facilitating its practical application in the design and orientation of additively manufactured components.

LPBF is an additive manufacturing technique that allows the building of complex geometries. Its process parameters directly influence the microstructure of the material. Inconel 718 is a nickel-based superalloy with excellent mechanical properties and oxidation resistance at elevated temperatures. However, when built by AM, its anisotropic microstructural character can influence the oxidation resistance, impairing the mechanical integrity. This work investigates the effects of high temperature exposure on the LPBF IN718. Samples manufactured with two different scanning strategies and with and without age-hardening heat treatment were prepared in three different orientations: X, Y and Z, and subjected to oxidation tests at 1000 °C for 24 h in order to measure the mass variation and characterize their surfaces. Conventional forged samples were used for comparison. ANOVA, OM, SEM-EDS and XRD analyses showed a strong influence of both parameters on the oxidation of all faces. The samples produced using 0° angle had better performance compared to 67°, with less mass gain. Heat treatment promoted grain recrystallization, improving the resistance to oxidation in some cases. Faces X and Y presented similar mass gains at 0°, with better performance for non-treated samples. Face Z showed the lowest mass gain, with better performance for treated samples.

The anisotropic mechanical behavior of laser powder bed fused (LPBF) IN718 results from the combined effects of crystallographic texture and grain morphology, although their individual contributions remain difficult to quantify. In this work, six representative volume elements (RVEs) are systematically compared using a unified EBSD–Dream3D–DAMASK crystal plasticity framework to separate the effects of texture and morphology. The microstructures include two EBSD-derived RVEs, two discretized columnar RVEs, and two discretized lamellar RVEs generated from identical orientation distributions. Predicted elastic moduli and yield strengths are validated against experiment, while Taylor factor analysis, directional effective grain size, slip compatibility, KAM, and local crystal plasticity fields are used to identify the governing deformation mechanisms. The results show that crystallographic texture predominantly controls the elastic response, whereas grain morphology governs the onset of plastic deformation. Lamellar RVEs provide the closest agreement with the experimental yield-strength anisotropy by reproducing the directional effective grain size, the connectivity of mechanically hard domains, and the resulting redistribution of stress and plastic strain. Furthermore, texture discretization preserves the dominant anisotropic trends while substantially reducing the computational cost of full EBSD reconstructions, establishing an efficient and physically meaningful framework for crystal plasticity simulations of LPBF materials.

La fabricación aditiva de polímeros reforzados con fibras ofrece nuevas posibilidades para el diseño estructural; sin embargo, su respuesta bajo carga biaxial permanece dispersa y poco consolidada. Esta revisión sistemática analiza polímeros reforzados con fibras fabricados aditivamente y sometidos a cargas biaxiales. Se buscaron publicaciones entre enero de 2014 y agosto de 2025 en Scopus, Web of Science, ScienceDirect, IEEE Xplore, SpringerLink, Dialnet, Redalyc, SciELO y Redib. De los 281 registros identificados, 52 estudios cumplieron los criterios de elegibilidad y se incluyeron en la síntesis temática y el análisis bibliométrico. La evidencia se clasificó como directa, indirecta, transferida desde compuestos convencionales o habilitadora desde el punto de vista metodológico. Los resultados revelan una base experimental limitada, una marcada heterogeneidad en las probetas y los protocolos de ensayo, una validación insuficiente de los modelos numéricos y pocos criterios predictivos calibrados para defectos inducidos por la impresión. Los enfoques de elementos finitos, multiescala y aprendizaje automático muestran potencial, pero requieren verificación sistemática, validación experimental y análisis de sensibilidad. Se propone una representación local σ₁₁–τ₁₂ como marco comprobable para construir envolventes de falla físicamente interpretables; su ventaja comparativa aún no ha sido demostrada. Las investigaciones futuras deberían priorizar la estandarización experimental, la trazabilidad de los datos, la validación de modelos y la evaluación ambiental.

This work presents a comprehensive computational analysis of the fracture behavior in nanocrystalline aluminum, addressing challenges relevant to advanced manufacturing environments. Molecular Dynamics simulations were conducted to estimate the plastic zone at the crack tip, combining atomistic insights with continuum mechanics approaches. Local stress fields were calculated using the Hardy formalism, while the global mechanical response was assessed via the Virial stress tensor. The size of the plastic zone was determined through both classical Linear Elastic Fracture Mechanics ($K_{I}$) and Elastic-Plastic Fracture Mechanics (J-integral, CTOD) criteria. Results indicate that conventional linear models significantly underestimate the plastic zone extent at the nanoscale, whereas the CTOD-based method aligns more closely with atomistic simulations. These findings underscore the importance of integrating atomistic and continuum methodologies to improve the predictive accuracy of fracture analysis in nanoscale metallic systems, thereby supporting the design of high-performance materials and structures in manufacturing processes.