Search Results (93)

The aim of the research was to analyse the impact of peening each of the beads on the properties of a butt joint made of S960QL steel welded with ceramic backing on a robotic workstation using the 135 (MAG) method, and to determine the impact of pneumatic needle peening on the stress level. This analysis was based on a comparison of three butt joints: in the as-welded state, with each weld bead peened and post-weld heat treatment—stress relief annealing—performed. High-frequency peening (90 Hz) of each weld was performed to reduce stresses in the welded joint by introducing tensile stresses into it. A Weld Line 10 pneumatic hammer from PITEC GmBH was used for this purpose. The test joints obtained were tested in accordance with the requirements of EN ISO 15614-1. In order to determine the state of residual stresses, stress measurements were carried out using the Barkhausen effect based on the testing procedure of the technology supplier, NNT. This meter measures the intensity of the Barkhausen effect using a standard probe (with a single core). In order to verify the stress measurement using the Barkhausen method, stress measurements were performed using the XRD sin 2ψ technique based on the X’Pert Stress Plus program, which contains a database of material constants necessary for calculations. Structural studies, including phase analysis and crystallographic grain orientation, were performed using the backscattered electron diffraction method with a high-resolution scanning electron microscope and an EBSD (Electron Backscatter Diffraction) detector, as well as EDAX OIM analysis software. In addition, X-ray diffraction testing was performed on a Panalytical X’Pert PRO device using filtered cobalt anode tube radiation (λ = 1.79021 A). Qualitative X-ray phase analysis of the tested materials was performed in a Bragg–Brentano system using an Xcelerator strip detector. The tests showed that the high-frequency peening of each bead did not cause negative results in the required tests during qualification of the S960QL plate-welding technology compared to the test plates in the as-welded and post-stress-relief heat treatment states. Interpass peening of the weld face and HAZ resulted in a reduction in residual stresses after welding at a distance of 15 mm from the joint axis compared to the stress measurement result for the sample in the as-welded condition. This allows for a positive assessment of peening in terms of reducing the crack initiator in the form of the concentration of tensile stresses in the area of the fusion line and HAZ. Full article

Background and Objectives: Unilateral spinal stabilization has emerged as a less invasive alternative to bilateral fixation in the management of lateralized spinal pathologies. While both rigid and dynamic systems are utilized, comparative data regarding their clinical efficacy, radiological outcomes, and complication profiles—particularly in multilevel applications—remain limited. Materials and Methods: A retrospective, two-center analysis was conducted on 113 patients who underwent unilateral posterior spinal stabilization between 2019 and 2023. Patients were divided into unilateral rigid stabilization (URS, n = 41) and unilateral dynamic stabilization (UDS, n = 72) groups. Pathologies of the patients include disc herniations, foraminal and spinal stenosis, tumoral lesions and spondylolisthesis. Clinical outcomes were assessed using the Visual Analogue Scale (VAS) over a 24-month follow-up. Radiological parameters included fusion status, superior adjacent disc height, and foraminal height index. Complication rates, including adjacent segment degeneration (ASD), pseudoarthrosis, and screw loosening, were analyzed according to type-of-stabilization and construct length (two, three, or four levels). Results: Both URS and UDS groups demonstrated significant VAS improvement at final follow-up, with no significant differences between groups (p < 0.001). Fusion rates were significantly higher in the URS group (85.37% vs. 27.78%, p < 0.001), while pseudoarthrosis (39.02% vs. 16.62%, p = 0.081) were more frequent in URS. No cases of rod fracture or infection were observed. Complication rates, particularly ASD, increased with longer constructs (6.56%, 21.21%, vs. 31.58% p = 0.01), independent of stabilization type. Conclusions: Unilateral stabilization—whether rigid or dynamic—offers effective symptom relief with reduced surgical morbidity. However, dynamic systems may provide biomechanical advantages by preserving motion and minimizing adjacent segment stress. While rigid constructs yield higher fusion rates, they are associated with increased complications. These findings support the use of dynamic stabilization, particularly in multilevel constructs, and highlight the need for patient-specific surgical strategies to optimize outcomes and mitigate long-term complications. Full article

Plasma-facing components (PFCs) are among the most critical functional components in a nuclear fusion device. Their reliability and durability under high heat loads are directly tied to the safe operation and lifetime of the fusion device. Under cyclic high thermal loads, accumulated plastic strain can lead to material property degradation. Furthermore, severe temperature gradients generate alternating tensile and compressive stresses within the material, resulting in the initiation and propagation of microcracks, ultimately causing structural failure of the PFCs. This study focuses on the issues of thermal stress concentration and plastic strain accumulation at the tungsten (W)/copper (Cu) joint interface and proposes an optimized design scheme based on a laminated tungsten structure. Using a combined approach of finite element simulation and theoretical analysis, the effects of tungsten layer thickness and interface geometry on the thermomechanical performance of the PFC joint were systematically investigated. The results indicate that reducing the thickness of tungsten sheet can significantly decrease the interfacial stress level. As the tungsten sheet thickness is reduced from the millimeter scale to the micrometer scale, the thermal mismatch at the W/Cu interface is reduced, thereby leading to a notable reduction in normal stress along the axial direction. In particular, when the thickness falls below 10 μm, the axial normal stress approaches zero, and the equivalent stress at the interface is effectively mitigated. Further research indicates that optimizing the flat W/Cu interface into an arc-shaped interface can alter the location of stress concentration. When the ascending distance of the Cu exceeds 600 μm, the stress concentration at the interface vertex is essentially eliminated. However, an excessively ascending distance of the Cu can exacerbate plastic deformation in the copper layer. By optimizing the extended distance of the Cu, a balance between stress relief and plastic strain accumulation can be effectively achieved. Full article

The stress concentration, which appears in loaded structural elements with voids, holes or undercuts, is the main source of premature fatigue failure. So, an increase in fatigue life can be achieved by reducing stress concentrations around the notches. Different techniques can be used to reduce the stress concentration. One of them is the application of additional stress relief undercuts or holes, while a second one relies on the application of overlays glued in the vicinity of notches. The proposed study is focused on the optimisation of notched specimens using a multi-stage optimisation process, including the use of artificial neural networks (ANNs). On this basis, the comparison of the effectiveness of various modern finite element optimisation tools is made. Here, special attention is paid to samples with elliptical holes and the application of the ANN technique in determining the optimal solution for the configuration of stress relief holes. The proposed study is illustrated by the example of a steel specimen with an elliptical opening. Specimens without stress relief holes and with an optimal configuration of stress relief holes are subjected to fatigue tests to confirm the effectiveness of the proposed approach. The performed study revealed that the cutting of additional circular stress relief holes reduces the stress concentration around the elliptical opening by about 12% and leads to an increase in fatigue life by about 79% for the applied material. Moreover, the comparison of the possibilities of the reduction in SCF by the application of stress relief holes, composite overlays and the simultaneous application of composite overlays and stress relief holes for the investigated notched samples is performed. Following the numerical results, it is observed that the use of composite overlays additionally decreases the stress concentration factor in relation to specimens with stress relief holes by an additional 6%. Full article

ADHD and misophonia are developmental neurological disorders that are currently increasing in prevalence due to excessive acoustic and visual pollution. ADHD, which is characterized by a lack of attention and excessive impulsive hyperactivity, and misophonia, which is hypersensitivity to sounds accompanied by a severe emotional and psychological reaction, are both affected by the user’s spatial environment to a great extent. Spatial design can contribute to increasing or decreasing these unfavorable sensory triggers that affect individuals with ADHD and/or Misophonia. However, the role of architectural spatial design as a therapeutic approach to alleviate the symptoms of Misophonia and ADHD has never been proposed before in the literature, despite its accumulative and chronic effects on the user’s experience in everyday life in terms of well-being and productivity. Therefore, the current work discusses this problem of neglecting the potential effect of architectural spatial design on alleviating Misophonia and ADHD. Thus, the objective of the current work is to propose customized architectural spatial design as a therapeutic approach to alleviate Misophonia and ADHD through adopting the compatible architectural trends of minimal and metaphysical architecture. The methodology of the current work includes a theoretical proposal of this customized architectural spatial design for alleviating these two special neurological conditions. This includes introducing and analyzing these two neurological conditions and their relation to and interaction with architectural spatial design, analyzing minimal and metaphysical architectural trends employed in the proposed therapeutic architectural design, and then proposing augmented and virtual reality as auxiliary add-ons to the architectural spatial design to boost its therapeutic effect. Minimal architecture achieves the “no emotion” criteria through reduced forms, patterns, and colors and adopts simple geometry and natural materials to reduce sensory stressors or stimuli, in order to alleviate the loss of attention and distraction prevalent in those with ADHD, as well as allowing the employment of acoustic materials to achieve acoustic comfort and noise blockage for Misophonia relief. Metaphysical architecture leads the hierarchy of sensory experience through the symbolistic, dynamic, and enigmatic composition of forms and colors, which enhance the spatial analysis and cognitive capacities of the inhabitants. Meanwhile, the use of customized virtual and augmented reality environments is an effective add-on to minimal and metaphysical architectural spaces thanks to its proven therapeutic effect in alleviating various neurological disorders and injuries. At this level of intervention, VR/AR can be used as an add-on to minimal-architecture design, to simulate varied scenarios, as minimal design offers a clean canvas for simulating these varied virtual environments. The other option is to build these customized VR/AR scenarios around a specific architectural element as an add-on metaphysical architecture design to lead the sensory experience and enable the user to detach from the physical constraints of the space. AI-generated designs were used as a proof of concept for the proposed customized architectural spatial design following minimal and metaphysical architecture, as well as to provide AR and VR scenarios as add-on architecture to enhance the therapeutic effect of these architectural spaces for Misophonia and ADHD patients. Furthermore, the validity of VR/AR as a therapeutic approach, alongside the customized architectural design, was discussed, and it was concluded that this study proves the need for extended clinical studies on its efficiency in the long run, which will be conducted in the future. Full article

Deep multi-coal seam mining is plagued by intense mining pressure, significant impacts of multi-working face mining on system roadways, and difficult surrounding rock deformation control—these issues severely threaten the safe and normal operation of roadways, creating an urgent need for effective dynamic disaster control technologies. Taking the 131,105 working face of Liuzhuang Mine (burial depth up to 740 m) as an example, this study addresses a critical research gap; existing roof cutting pressure relief technologies mostly focus on shallow/thin-coal-seam mining and fail to tackle secondary dynamic pressure induced by repeated mining in deep multi-coal seams—where the superposition of mining stress, ground stress, and goaf stress severely threatens system roadways. To fill this gap, three novel contributions are made. (1) A hierarchical “upper break and middle cut” deep-hole blasting design is proposed, distinct from single-mode roof cutting in existing studies. It achieves directional roof failure by “upper break” (damaging overlying hard rock) and “middle cut” (creating fissures between goaf and protective coal pillars), blocking stress transmission to roadways. (2) Numerical simulations specifically for deep strata (740 m) optimize key parameters: 25 m as the optimal cutting height and 35° as the optimal cutting angle, quantifying their effects on pressure relief (a gap in existing parameter optimization for deep mining). (3) A rapid sealing scheme combining AB material grouting with high-strength detonator pins is developed, solving the problem of slow hardening and poor sealing in traditional deep-hole processes (e.g., cement-only sealing), enabling blasting within 10 min after sealing. This cut off the integrity of the roof, blocked the pressure transmission of the roof stress to the existing system roadway, and achieved a 43.7% reduction in roadway surrounding rock stress (from 32 MPa to 18 MPa) and a 46.7% reduction in maximum roadway deformation (from the pre-blasting 15 cm to 8 cm). This study provides a reference for similar deep multi-coal seam projects. Field monitoring and numerical simulation results show the following. (1) The maximum deformation of the protected East Third Concentrated main roadway is only 8 cm, fully meeting normal operation requirements. (2) The “upper break and middle cut” technology effectively reduces the mining influence range (from 156 m without roof cutting to 125 m with 25 m roof cutting) and weakens roof stress transfer to roadways. This study verifies the feasibility and effectiveness of deep hole blasting for roof cutting, pressure relief, and roadway protection in deep multi-coal seam mining. It provides direct technical references and engineering application templates for similar projects facing roadway protection and dynamic disaster control challenges, contributing to the safe and efficient mining of deep coal resources. Full article

The reduced ductility caused by the brittle needle-like α′ martensite limits the application of TC4 alloys produced by selective laser melting (SLM). Appropriate heat treatment can improve the microstructures and properties of SLM-fabricated TC4 alloys. In this work, SLM-fabricated TC4 alloys underwent stress relief annealing at 600 °C and high-temperature annealing at 800 °C. The effects of heat treatment temperature on phase composition, microstructural morphology, grain orientation, and mechanical properties were investigated. Meanwhile, the microstructural evolution and fracture mechanisms during the heat treatment process were analyzed. The results indicate that after annealing at 600 °C, the needle-like α′ phase transforms into elongated α, and nano-β phase increases. When annealed at 800 °C, the α′ phase completely transforms into a more stable lath-shaped α phase and a short rod-shaped β phase, with the nano-β phase disappearing. The texture orientation gradually shifts from <0001> towards <01-10>, where slip systems are more active. Additionally, heat treatment promotes the transition of grain boundaries to high-angle grain boundaries, thereby alleviating stress concentration and enhancing solid-solution strengthening. After heat treatment, the ultimate tensile strength of the material slightly decreases, but the elongation significantly increases. As the annealing temperature increased, the elongation (EL) improved from 5.22% to 11.43%. Following high-temperature annealing at 800 °C, necking and larger dimples appear on the fracture surface, and the fracture mechanism shifts from a mixed brittle–ductile fracture to a ductile fracture. This work provides a theoretical basis for improving the microstructures and properties of SLM-fabricated TC4 alloys through heat treatment. Full article

In the mining of deep mineral resources and tunnel engineering, the degradation of mechanical properties and the evolution of energy of through-double-joint sandy slate under triaxial loading and unloading conditions are key scientific issues affecting the stability design of the project. The existing research has insufficiently explored the joint inclination angle effect, damage evolution mechanism, and energy distribution characteristics of this type of rock mass under the path of increasing axial pressure and removing confining pressure. Based on this, in this study, uniaxial compression, conventional triaxial compression and increasing axial pressure, and removing confining pressure tests were conducted on four types of rock-like materials with prefabricated 0°, 30°, 60°, and 90° through-double-joint inclinations under different confining pressures. The axial stress/strain curve, failure characteristics, and energy evolution law were comprehensively analyzed, and damage variables based on dissipated energy were proposed. The test results show that the joint inclination angle significantly affects the bearing capacity of the specimen, and the peak strength shows a trend of first increasing and then decreasing with the increase in the inclination angle. In terms of failure modes, the specimens under conventional triaxial compression exhibit progressive compression/shear failure (accompanied by rock bridge fracture zones), while under increased axial compression and relief of confining pressure, a combined tensioning and shear failure is induced. Moreover, brittleness is more pronounced under high confining pressure, and the joint inclination angle also has a significant control effect on the failure path. In terms of energy, under the same confining pressure, as the joint inclination angle increases, the dissipated energy and total energy of the cemented filling body at the end of triaxial compression first decrease and then increase. The triaxial compression damage constitutive model of jointed rock mass established based on dissipated energy can divide the damage evolution into three stages: initial damage, damage development, and accelerated damage growth. Verified by experimental data, this model can well describe the damage evolution characteristics of rock masses with different joint inclination angles. Moreover, an increase in the joint inclination angle will lead to varying degrees of damage during the loading process of the rock mass. The research results can provide key theoretical support and design basis for the stability assessment of surrounding rock in deep and high-stress plateau tunnels, the optimization of support parameters for jointed rock masses, and early warning of rockburst disasters. Full article

Cavitation-induced degradation of metallic materials presents a significant challenge for engineers and users of equipment operating with high-velocity fluids. For any metallic material, the mechanical strength and ductility characteristics are controlled by the mobility of dislocations and their interaction with other defects in the crystal lattice (such as dissolved foreign atoms, grain boundaries, phase separation surfaces, etc.). The increase in mechanical properties, and consequently the resistance to cavitation erosion, is possible through the application of heat treatments and cold plastic deformation processes. These factors induce a series of hardening mechanisms that create structural barriers limiting the mobility of dislocations. Cavitation tests involve exposing a specimen to repeated short-duration erosion cycles, followed by mass loss measurements and surface morphology examinations using optical microscopy and scanning electron microscopy (SEM). The results obtained allow for a detailed study of the actual wear processes affecting the tested material and provide a solid foundation for understanding the degradation mechanism. The tested material is the Ni-based alloy INCONEL 625, subjected to stress-relief annealing heat treatment. Experiments were conducted using an ultrasonic vibratory device operating at a frequency of 20 kHz and an amplitude of 50 µm. Microstructural analyses showed that slip bands formed due to shock wave impacts serve as preferential sites for fatigue failure of the material. Material removal occurs along these slip bands, and microjets result in pits with sizes of several micrometers. Full article

Expansion relief groove (ERG) controlling excess arch expansion has become a research hotspot. Based on statistical arch expansion data, this paper proposes a novel structural design for ERG, selecting asphalt-treated base (ATB-25) and graded gravel (GG) as fill materials for trial paving. Through three years of monitoring, the temperature, stress, and displacement across the two solutions were comparatively analyzed to evaluate their control effectiveness. The results indicated five points. (1) The reasonable spacing of the expansion through should be 200 m, and the width should not be less than 50 cm in ERG structure design. (2) The annual temperature difference of ATB-25 ERG (55 °C) > GG ERG (51 °C) > cement-treated base (CTB) (47 °C). The large annual temperature difference causes the expansion of the base. (3) The performance of ERGs is highly correlated with the seasonal alternation. The compressive stress increases in summer, resulting in compressive deformation, and decreases in winter, resulting in extended deformation. (4) According to three years of monitoring, the plastic deformation accumulated, and the compression deformation in the two ERGs increased to 155% and 943.47% of that in the first year. The expansion pressure in the base layer is constrained, resulting in compression deformation of the base. (5) GG is more suitable as the filler of the ERG to deal with arch expansion disease and demonstrates excellent cost-effectiveness. Full article

Urbanization and climate change present increasing challenges to outdoor human thermal comfort, particularly in university campuses where academic, social, and recreational activities converge. This study assesses microclimatic risk factors along the main avenue of the NOVA FCT campus by analyzing outdoor human thermal comfort using the physiologically equivalent temperature (PET) and modified PET (mPET) indices. Field measurements of air temperature, humidity, wind velocity, and radiation were conducted at multiple Points Of Interest (POIs) to evaluate thermal stress levels and identify critical zones of discomfort. Results indicate significant spatial and temporal variations in thermal stress, with sun-exposed areas (G2) experiencing PET values exceeding 50 °C, during peak summer hours, while shaded locations (G1) showed substantial thermal relief (PET reductions up to 27 °C between G1 and G2 POIs). Wind velocity and urban morphology played crucial roles in modulating microclimatic conditions. Wind velocity above 2.0 m/s was associated with perceptible thermal relief (3–8 °C PET/mPET reduction), especially in narrow, shaded passages. Significant spatial variability was observed, linked to differences in urban morphology, surface materials, and vegetation coverage. This research provides actionable insights for urban planners and campus administrators, contributing to the development of more sustainable and thermally comfortable outdoor environments in educational settings. Full article

Background: The quality of palliative care (PC) services is closely linked to the effectiveness of interdisciplinary collaboration. A coordinated approach among professionals from different fields fosters holistic, person-centered care, ensuring comprehensive support for patients with complex conditions and their families. In hospital settings, In-Hospital Palliative Care Support Teams (EIHSCPs) play a key role in delivering specialized care, enhancing interdepartmental communication, training other healthcare professionals, and optimizing resources. Strong leadership by PC specialists, combined with effective team management, contributes to symptom relief, improved quality of life, and cost reduction. However, interdisciplinary collaboration presents challenges, including competing priorities, resource constraints, and communication barriers. Despite its recognized benefits, research on its implementation in PC, particularly in Portugal, remains scarce. Objective: This study explores the perspectives and practices of professionals within an EIHSCP, examining team dynamics, interprofessional collaboration, and key facilitators and barriers. Methods: Twelve semi-structured interviews were conducted with physicians, nurses, psychologists, and social workers from the EIHSCP in the Médio Tejo region. Data were analyzed using Braun and Clarke’s reflexive thematic analysis. Results: The interview findings were organized into three themes: (1) Social Representations and Interdisciplinary Practice; (2) Competencies for Interdisciplinary Practice; and (3) Challenges in Interdisciplinary Practice. Participants consistently highlighted that interdisciplinary collaboration enhances communication between services and improves care quality. While teamwork is central, patient- and family-centered care remains the priority. Key competencies include empathy, ethics, active listening, and cultural sensitivity, alongside structural and procedural elements such as team meetings, integrated communication, and clear referral criteria. Continuous education and professional development are essential. Challenges primarily stem from limited human and material resources, staff workload and stress, communication gaps between hospital and community teams, and insufficient institutional recognition. Suggested improvements focus on investing in ongoing training, strengthening communication and inter-institutional collaboration, and revising the organizational model of PC within Portugal’s National Health Service. Conclusions: Interdisciplinary collaboration in PC is fundamental for holistic, patient-centered care but is hindered by structural and organizational barriers. Full article

This article provides a comprehensive, step-by-step framework that bridges the gap between the theory and engineering practical applications of Powder Bed Fusion (PBF) technology for producing high-quality metal parts suitable for end users. This proposed framework integrates multiple aspects into a coherent methodology on how to evaluate the PBF parameters and processing conditions, in order to establish a reliability scale for the PBF process on the Realizer 250 SLM machine. Experimental research, conducted over the past 10 years, reveals that the PBF process often encounters challenges related to process stability and part consistency. To address these issues, this paper introduces a novel method for evaluating the manufacturing process by considering the obtained physico-mechanical characteristics. The determined properties of PBF samples were ultimate tensile strength, Young’s modulus, the Poisson ratio, maximum elongation, hardness, and surface roughness. Test specimens were fabricated and tested without applying a stress relief heat treatment. Four bio-metal materials were studied as follows: pure Titanium, Ti6Al7Nb, CoCr, and CoCrWMo. Optimal processing parameters were established for each material focused on laser power, scanning speed, and hatch distance. To have a high chance of successfully printing, each material has its own set of PBF parameters. The results showed that the mechanical resistance can be up to 441 MPa for pure Ti (parameters 120 W, 500 mm/s, 0.12 mm) and 1159 MPa for CoCrWMo alloys (parameters 85 W, 500 mm/s, 0.10 mm). The mechanical properties of these materials are presented, offering valuable data for finite element analysis (FEA) necessary for designing medical implants. This paper provides practical guidelines beneficial for both medical application designers and manufacturers using PBF technology, contributing to enhanced reliability and efficiency in PBF-based metal part production. Full article

Background and Objectives: This study aimed to evaluate the efficacy and safety of modified laparoscopic Burch intervention over a 24-month follow-up period. Materials and Methods: We performed a retrospective cohort evaluation including all eligible patients, 83 patients, who underwent modified laparoscopic Burch colposuspension for stress urinary incontinence (SUI). Primary outcomes included the presence or absence of SUI on follow-up and the success of index surgery based on responses to validated questionnaires of patient-reported outcomes. Results: Patient-reported outcomes indicated a progressive improvement in perceived well-being over time. At the 6-month follow-up, 50.6% of participants reported their condition as “greatly improved”, increasing cumulatively to 66.7% by 24 months. The severity of urinary incontinence symptoms was markedly reduced following the intervention. The incidence of severe incontinence was notably low, with only 4.8% of patients affected at 6 months, remaining consistent at 5.1% at 24 months. This finding aligns with a high procedural success rate, as the vast majority of patients (≥94.9%) reported no severe symptoms across all follow-up intervals. Dryness, defined as the absence of urinary leakage, demonstrated an upward trend over time. At 6 months, 45.8% of patients reported complete dryness, with this figure rising to 55.1% at 12 months and 62.8% at 24 months. The Urogenital Distress Inventory-6 (UDI-6) served as a critical metric for evaluating the subjective burden of urinary symptoms. Across all follow-up intervals, over 97% of patients achieved scores below the clinically significant threshold (<33), indicating substantial symptom relief and enhanced quality of life. Conclusions: The modified laparoscopic Burch colposuspension demonstrated consistent efficacy, with significant improvements in urinary continence, symptom severity, and quality of life over the 24-month follow-up period. Full article

The use of parts containing internal channels fabricated by laser powder bed fusion (LPBF) in maraging steel is gaining attention within industry, due to the promising application of the material in molds and forming tools. However, LPBF processing has issues when it comes to unsupported channels, leading to defects that can result in a limited performance and shortened component life. The present study aims to provide a detailed evaluation of the metallurgical effects arising from the LPBF printing of channels made of maraging 300 steel. The results show that channel distortion occurs due to the lack of support, associated with increased roughness at the top part of the channel profile caused by partial melting and loosening of the powder. Statistical analyses showed that distortion is significantly affected by channel length. A high level of porosity derived from a lack of fusion was observed in the region above the channel and was attributed to layer irregularities caused by the absence of support, with a predominance of large and irregular pores. Residual stresses, always of a tensile nature, present a behavior opposed to that of distortion, increasing with increases in length, meaning that higher levels of distortion lead to an enhanced effect of stress accommodation/relief, with porosity having a similar effect. All these phenomena, however, did not seem to affect crystallographic orientation, with a nearly random texture in all cases, most likely due to the energy input used and to an optimized laser scanning strategy. These findings are vital to increase the amount of attention paid towards the design of internal channels, especially with those with the purpose of coolant circulation, since distortions and poor surface finishing can reduce cooling efficiency due to a defective fluid flow, while porosity can have the same effect by hindering heat transfer. Residual stress, in its turn, can decrease the life of the component by facilitating cracking and wear. Full article