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Additive manufacturing (AM) is a layer-by-layer technique that helps to create physical objects from a three-dimensional data set. Fused deposition modeling is a widely used material extrusion (MEX)-based AM technique that melts thermoplastic filaments and selectively deposits them over a build platform. Despite its simplicity and affordability, it suffers from various printing defects, with partial warping being a prevalent issue. Warpage is a physical deformation caused by thermal strain incompatibility that results in the bending of the printed part away from the build platform. This study aims to investigate the warpage characteristics of printed parts based on geometrical parameters and build orientations to reduce the warpage extent.

Cuboidal samples of thermoplastic acrylonitrile butadiene styrene ranging from 5 to 80 mm were printed using a commercial MEX system. A Taguchi method-based design of experiment trial was performed to optimize the placement and orientation of the part for minimal warpage.

It was found that a lower value of the “in-plane” aspect ratio and a more prominent part thickness are favorable for minimal warpage. The part should always be placed near the region with the highest temperature (least thermal gradient) to minimize the warpage.

A novel dimensionless parameter (Y) is proposed that should be set to a minimum value to achieve minimal warpage. The results of this study can help improve the design and part placement for the MEX technique, thus elevating the print quality.

This study aims to improve the acceleration in the additive manufacturing (AM) process. AM tools, such as extrusion heads, jets, electric arcs, lasers and electron beams (EB), experience negligible forces. However, their speeds are limited by the positioning systems. In addition, a thin tool must travel several kilometers in tiny motions with several turns while realizing the AM part. Hence, acceleration is a more significant limiting factor than the velocity or precision for all except EB.

The sawtooth (ST) scanning strategy presented in this paper minimizes the time by combining three motion features: zigzag scan, 45º or 135º rotation for successive layers in G00 to avoid the CNC interpolation, and modifying these movements along 45º or 135º into sawtooth to halve the turns.

Sawtooth effectiveness is tested using an in-house developed Sand AM (SaAM) apparatus based on the laser–powder bed fusion AM technique. For a simple rectangle layer, the sawtooth achieved a path length reduction of 0.19%–1.49% and reduced the overall time by 3.508–4.889 times, proving that sawtooth uses increased acceleration more effectively than the other three scans. The complex layer study reduced calculated time by 69.80%–139.96% and manufacturing time by 47.35%–86.85%. Sawtooth samples also exhibited less dimensional variation (0.88%) than zigzag 45° (12.94%) along the build direction.

Sawtooth is limited to flying optics AM process.

Development of scanning strategy for flying optics AM process to reduce the warpage by improving the acceleration.

Integrating additive manufacturing (AM) tools in traditional mold-making provides complex yet affordable sand molds and cores. AM processes such as selective laser sintering (SLS) and Binder jetting three-dimensional printing (BJ3DP) are widely used for patternless sand mold and core production. This study aims to perform an in-depth literature review to understand the current status, determine research gaps and propose future research directions. In addition, obtain valuable insights into authors, organizations, countries, keywords, documents, sources and cited references, sources and authors.

This study followed the systematic literature review (SLR) to gather relevant rapid sand casting (RSC) documents via Scopus, Web of Science and EBSCO databases. Furthermore, bibliometrics was performed via the Visualization of Similarities (VOSviewer) software.

An evaluation of 116 documents focused primarily on commercial AM setups and process optimization of the SLS. Process optimization studies the effects of AM processes, their input parameters, scanning approaches, sand types and the integration of computer-aided design in AM on the properties of sample. The authors performed detailed bibliometrics of 80 out of 120 documents via VOSviewer software.

This review focuses primarily on the SLS AM process.

A SLR and bibliometrics using VOSviewer software for patternless sand mold and core production via the AM process.

This paper aims to use hybrid manufacturing (HM) to overcome several drawbacks of material extrusion three-dimensional (3D) printers, such as low dimension ranging from 0.2 to 0.5 µm, resulting in a noticeable staircase effect and elevated surface roughness.

Subtractive manufacturing (SM) through computer numerical control milling is renowned for its precision and superior surface finish. This study integrates additive manufacturing (AM) and SM into a single material extrusion 3D printer platform, creating a HM system. Two sets of specimens, one exclusively printed and the other subjected to both printing and milling, were assessed for dimension accuracy and surface roughness.

The outcomes were promising, with postmilling accuracy reaching 99.94%. Significant reductions in surface roughness were observed at 90° (93.4% decrease from 15.598 to 1.030 µm), 45° (89% decrease from 26.727 to 2.946 µm) and the face plane (71% decrease from 12.176 to 3.535 µm).

The 3D printer was custom-built based on material extrusion and modified with an additional milling tool on the same gantry. An economic evaluation based on cost-manufacturing demonstrated that constructing this dual-function 3D printer costs less than US$560 in materials, offering valuable insights for researchers looking to replicate a similar machine.

The modified general 3D printer platform offered an easy way to postprocessing without removing the workpiece from the bed. This mechanism can reduce the downtime of changing the machine. The proven increased dimension accuracy and reduced surface roughness value increase the value of 3D-printed specimens.

This paper aims to offer a comprehensive review and categorization of production optimization throughout the additive manufacturing lifecycle in a cloud environment. It aims to provide a structured approach to identifying and addressing issues.

This paper systematically reviews 75 technical papers on cloud manufacturing, nesting, scheduling and postprocessing in additive manufacturing. This includes a detailed discussion of the key issues.

This paper introduces a production framework for the entire lifecycle of additive manufacturing in a cloud environment. This framework aids in problem identification and decision-making based on the process flow. It provides an integrated view from cloud to postprocessing, examining decision interdependencies and enhancing problem identification and organization.

To the best of the authors’ knowledge, this paper is the first to review the complete lifecycle of additive manufacturing, emphasizing the often-overlooked aspects of postprocessing and cloud manufacturing. It offers a comprehensive study of lifecycle optimization challenges and suggests ways to streamline the production process.

This study aims to propose and evaluate the progress in the basic-pixel (a strategy to generate continuous trajectories that fill out the entire surface) algorithm towards performance gain. The objective is also to investigate the operational efficiency and effectiveness of an enhanced version compared with conventional strategies.

For the first objective, the proposed methodology is to apply the improvements proposed in the basic-pixel strategy, test it on three demonstrative parts and statistically evaluate the performance using the distance trajectory criterion. For the second objective, the enhanced-pixel strategy is compared with conventional strategies in terms of trajectory distance, build time and the number of arcs starts and stops (operational efficiency) and targeting the nominal geometry of a part (operational effectiveness).

The results showed that the improvements proposed to the basic-pixel strategy could generate continuous trajectories with shorter distances and comparable building times (operational efficiency). Regarding operational effectiveness, the parts built by the enhanced-pixel strategy presented lower dimensional deviation than the other strategies studied. Therefore, the enhanced-pixel strategy appears to be a good candidate for building more complex printable parts and delivering operational efficiency and effectiveness.

This paper presents an evolution of the basic-pixel strategy (a space-filling strategy) with the introduction of new elements in the algorithm and proves the improvement of the strategy’s performance with this. An interesting comparison is also presented in terms of operational efficiency and effectiveness between the enhanced-pixel strategy and conventional strategies.

The study aims to identify the practical borders of AI legal personality and accountability in human-centric services.

Using a framework tailored for AI studies, this research analyses structured interview data collected from auditors based in Poland.

The study identified new constructs to complement the taxonomy of arguments for AI legal personality: cognitive strain, consciousness, cyborg paradox, reasoning replicability, relativism, AI misuse, excessive human effort and substitution.

The insights presented herein are primarily derived from the perspectives of Polish auditors. There is a need for further exploration into the viewpoints of other key stakeholders, such as lawyers, judges and policymakers, across various global contexts.

The findings of this study hold significant potential to guide the formulation of regulatory frameworks tailored to AI applications in human-centric services. The proposed sui generis AI personality institution offers a dynamic and adaptable alternative to conventional legal personality models.

The outcomes of this research contribute to the ongoing public discourse on AI’s societal impact. It encourages a balanced assessment of the potential advantages and challenges associated with granting legal personality to AI systems.

This paper advocates for establishing a sui generis AI personality institution alongside a joint accountability model. This dual framework addresses the current uncertainties surrounding human, general AI and super AI characteristics and facilitates the joint accountability of responsible AI entities and their ultimate beneficiaries.

This study aims to investigate the compression characteristics of the 3D-printed polylactic acid (PLA) samples at temperatures below the glass transition temperature (T_g) with varying strain rates and develop a thermo-mechanical viscoplastic constitutive model to predict the finite strain compression response using a single set of material parameters. Also, the micro-mechanical damage processes are linked to the global stress–strain response at varied strain rates and temperatures through scanning electron microscopy (SEM).

T_g of PLA was determined using a dynamic mechanical analyzer. Compression experiments were conducted at strain rates of 2 × 10^–3/s and 2 × 10^–2/s at 25°C, 40°C and 50°C. The failure mechanisms were examined using SEM. A finite strain thermo-mechanical viscoplastic constitutive model was developed to analyze the deformations at the considered strain rates and temperatures.

T_g of PLA was determined as 55°C. While the yield and post-yield stresses drop with increasing temperature, their trend reverses with an increased strain rate. SEM imaging indicated plasticizing effects at higher temperatures, while filament fragmentation and twisting at higher strain rates were identified as the dominant failure mechanisms. Using a non-linear regression analysis to predict the experimental data, an overall R² value of 0.98 was achieved between experimental and model prediction, implying the robustness of the model’s calibration.

In this study, a viscoplastic constitutive model was developed that considers the combined effect of temperature and strain rate for FDM-printed PLA experiencing extensive compression. Using appropriate temperature-dependent modulus and flow rate properties, a single set of model parameters predicted the rise in the gap between yield stress and degree of softening as strain rates and temperatures increased.

This study aims to investigate the impact of organizational mistreatments, such as workplace bullying and ostracism, on task performance. Additionally, it explores the mediating role of cyber loafing and the moderating role of negative reciprocity beliefs.

Adopting a positivism research philosophy and a deductive approach, this study focuses on the petroleum sector-related organizations where enterprise resource planning requires active Internet use, potentially leading to cyber loafing. Data were collected from employees using purposive sampling techniques, resulting in a sample size of 248. The data analysis was conducted using AMOS and SPSS software.

The results indicate that cyber loafing fully mediates the relationship between workplace bullying and ostracism on task performance. Additionally, negative reciprocity beliefs significantly moderate the relationship between workplace bullying, ostracism and cyber loafing.

This study presents a moderated-mediation model of organizational mistreatments and task performance, elucidating the mechanisms through the mediating role of cyber loafing and the moderating role of negative reciprocity beliefs.

The purpose of this study is to explore the effect of different post-curing times on the mechanical properties, specifically the visco-elastic characteristics, Poisson’s ratio and modulus, of three dimensional (3D) printed photopolymer composites (PPCs) reinforced with short glass fibres (SGF).

This research uses digital light processing-based Vat-photopolymerization process to 3D print PPCs reinforced with SGF at volume fractions of 2%, 4%, 6% and 8%. An inter-stage stirring process was used to reinforce the SGFs in a layer wise fashion. After printing, the parts undergo post-curing for 20, 60 and 100 min. The mechanical properties are then analyzed using dynamic mechanical analysis and in situ optical measurements. In addition, two-dimensional strain mapping from digital image correlation techniques is used to assess the structural behavior.

This study found that composites with 4% SGF reinforcement achieved the highest storage modulus, approximately 1,550 MPa, after 60 and 100 min of post-curing. In addition, the Poisson’s ratio of these composites increased from 0.2 to 0.41 with rising temperature. By applying Poisson’s ratio correction, the modulus was observed to be 1,800 MPa. These results indicate that optimal SGF content and post-curing times significantly enhance the mechanical properties of 3D-printed PPCs.

This research uniquely combines the reinforcement of photopolymers with SGFs at varying volume fractions and the detailed analysis of post-curing times to enhance the mechanical properties of 3D printed PPCs.