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Abstract The convergence of nanotechnology and bioprinting is redefining the landscape of tissue engineering, with nanocomposite gelatin methacryloyl (GelMA) bioinks emerging as a transformative platform for the biofabrication of multifunctional tissue‐specific constructs. GelMA, a photocrosslinkable hydrogel, has rapidly gained attention due to its intrinsic bioactivity, tunable mechanical properties, and compatibility with living cells. However, despite its wide applicability regenerating muscle, cartilage, bone, vascular, cardiac, and neural tissues, native GelMA suffers from limited mechanical strength and insufficient biofunctionality to recapitulate the complexity of specialized tissues. To overcome these shortcomings, recent strategies have focused on the incorporation of nanomaterials into GelMA matrices, ranging from inorganic and carbon‐based to metallic, polymeric, and lipidic nanomaterials. These nanocomposite bioprinted scaffolds impart critical enhancements, including improved mechanical robustness, electrical conductivity, stimuli‐responsiveness, and bioactivity, while also enabling advanced functionalities such as controlled drug release and real‐time responsiveness to the cellular microenvironment. This review examines the bioprinting parameters, material synergies, and design strategies governing the performance of nanocomposite GelMA bioinks. By integrating the tunability of photocrosslinkable bioinks with the multifunctionality of nanomaterials, nanocomposite GelMA bioinks represent a next‐generation platform capable of addressing the complex demands of tissue repair and regeneration. 

Abstract Additive manufacturing (AM) is now widely used for research and industrial production. The benchmark data for mechanical properties of additively manufactured specimens is very useful for many communities. This data article presents a tensile testing dataset of ASTM D638 size specimens without and with embedded internal geometrical features printed using polylactic acid (PLA) in a Fused Filament Fabrication (FFF) additive manufacturing process. The added features can mimic defects of various shapes and sizes. This work is a supplement to the published research articleAssisted defect detection by in-process monitoring of additive manufacturing using optical imaging and infrared thermography(Additive Manufacturing, 2023, 103483). The printed specimens were tensile tested. Stress-strain graphs were developed and used to calculate the mechanical properties such as ultimate tensile strength (UTS) and strain at UTS. The mechanical properties, the correlations between mechanical properties and size, shape and location of geometrical features (defects), and the trends in mechanical properties can be useful in benchmarking the results of other researchers. 

The primary objective of this study is to clarify the fundamental question of whether, in principle, it is possible to dispense with a prior solution annealing process in favor of a direct aging heat treatment for specimens of maraging stainless steel grade X3NiCoMoTi18‐9‐5 (1.2709) produced by laser powder bed fusion (LPBF). The waiver of a solution annealing process would significantly increase the process efficiency and thus support a sustainable and resource‐friendly production of such components. Therefore, the hardness, microstructure, and the present phases of specimens in as‐built + aged condition (AB + A) and solution‐annealed + aged (SOL + A) are examined during this study. Initially, an extended parameter study is performed using a Renishaw AM 250 LPBF system equipped with a pulsed mode laser system to achieve the highest possible apparent density. As test specimens, small cubes are produced for parameter study and are analyzed for porosity by means of optical microscopy. To investigate the relationship between microstructure and hardness in different material states, one series of specimens is aged directly after LPBF processing in the as‐built state (AB + A). For comparison, the other series was solution annealed at 820 °C for 60 min, quenched in water and then aged (SOL + A). A maximum hardness value of 614 HV1.0 is achieved for specimen aged at 490 °C for 120 min in as built condition (AB + A), while 624 HV1.0 was measured for specimen aged at 490 °C for 180 min in conventionally solution annealed + aged (SOL + A) condition. Significant austenite reversion is not observed at aging temperature of 490 °C in both cases. Aging of specimens at temperatures of 540 and 600 °C resulted in reduction of specimen hardness due to higher percentage of austenite reversion. No significant difference between the hardness values of AB + A and SOL + A specimens is observed. It can therefore be concluded that, in principle, conventional solution annealing and ageing can be dispensed with in favor of direct aging. However, as the results are based on small sized specimens, further investigations into the scalability are needed.