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This paper aims to investigate the influences of process parameters on part quality, electrical energy consumption. Moreover, the relationship between part quality and energy consumption of UTR9000 photosensitive resin fabricated by stereolithography apparatus (SLA) was also assessed.

Main effect plots and contour maps were used to analyze the interactions and effects of various parameters on energy consumption and part quality, respectively. Then, a growth rate was used defined as the percentage of the value of energy consumption (or the part quality) of the sample compared to the minimum value of the energy consumption (or the same part quality), to jointly analyze relationships between part quality and energy consumption on a specific process parameter.

The part qualities can be improved with increased energy consumption via adjusting layer thickness, without further increasing energy consumption through adjusting laser power, over-cure and scanning distance. Energy consumption can be highly saved while slightly decreasing the tensile strength by increasing layer thickness from 0.09 mm to 0.12 mm. Energy consumption and surface roughness can be decreased when setting laser power near 290 mW. Setting an appropriate over-cure of about 0.23 mm will improve tensile strength and dimensional accuracy with a little bit more energy consumption. The tensile strength increases nearby 5% at a scanning distance of 0.07 mm compared to that at a scanning distance of 0.1 mm while the energy consumption only increases by 1%.

In this research, energy consumption and multiple part quality for SLA are jointly analyzed first to accelerate the development of sustainable additive manufacturing. This can be used to assist designers to achieve energy-effective fabrication in the process design stage.

Active employment of additive manufacturing for scaffolds preparation requires the development of advanced methods which can accurately characterize the morphologic structure and its changes during an interaction of the scaffolds with substrate and aqueous medium. This paper aims to use the method of nuclear magnetic resonance (NMR) imaging for preclinical characterization of 3D-printed scaffolds based on novel allyl chitosan biocompatible polymer matrices.

Biocompatible polymer scaffolds were fabricated via stereolithography method. Using NMR imaging the output quality control of the scaffolds was performed. Scaffolds stability, polymer matrix homogeneity, kinetic of swelling processes, water migration pathways within the 3D-printed parts, effect of post-print UV curing on overall scaffolds performance were studied in details.

NMR imaging visualization of water uptake and polymer swelling processes during the interaction of scaffolds with aqueous medium revealed the formation of the fronts within the polymer matrices those dynamics is governed by case I transport (Fickian diffusion) of the water into polymer network. No significant difference was observed in front propagation rates along the polymer layers and across the layers stack. After completing the swelling process, the polymer scaffolds retain their integrity and no internal defects were detected.

NMR imaging revealed that post-print UV curing aimed to improve the overall performance of 3D-printed scaffolds might not provide a better quality of the finish product, as this procedure apparently yield strongly inhomogeneous distribution of polymer crosslink density which results in subsequent inhomogeneity of water ingress and swelling processes, accompanied by stress-related cracks formation inside the scaffolds.

This study introduces a method which can successfully complement the standard tests which now are widely used in either additive manufacturing or scaffolds engineering.

This work can help to improve the overall performance of the polymer scaffolds used in tissue engineering.

The results of this study demonstrate feasibility of NMR imaging for preclinical characterization of 3D printed biocompatible polymer scaffolds. The results are believed to contribute to better understanding of the processes vital for improving the design of 3D-printed polymer scaffolds.

This paper describes the use of parametric modelling techniques in the design of drinking bottles. A customised application programme is developed and integrated for the design and manufacture of a blow mould bottle within a proprietary CAD/CAM software named Duct5. One such conceptual design is physically realized and verified through the use of the stereolithography technique. Overall, by equipping designers with a library of “bottle‐design” features from a CAD/CAM system, the design period is shortened and simplified, and the same geometrical data can be passed downstream for manufacturing.

Many engineering and scientific problems require the filling of a two‐dimensional region with scan lines of finite width. The number of contiguous scan line segments required for the filling depends on the direction used for scanning. When the cost of the filling operation increases with the number of scan line segments, as is the case in numerically controlled machining, layered fabrication and computer graphics applications, then it is desirable to select a direction that minimizes this number. In this paper we provide a method for efficiently computing such an optimal direction when the region to be filled is bounded by straight‐line segments and/or circular arcs.