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Ceramic three‐dimensional parts can be produced by a stereolithography (SL) process using a ceramic suspension containing alumina powder, UV curable monomer, diluent, photoinitiator and dispersant. The monomer reacts to UV radiation (argon ionized laser) and is transformed into a solid polymer which is then removed by thermal treatment (debinding). Subsequent sintering of green parts leads to dense ceramic parts. The effect of each component on the rheology of the alumina suspensions has been studied first. Both the addition of dispersant and diluent and the increase in temperature allow a significant decrease of the viscosity of the suspensions. The highly loaded (more than 55 vol. per cent), homogeneous and stable suspensions have a shear thinning behaviour which is favourable for casting the layers. Adequate cured depth (above 200μm) and satisfactory transversal resolution have been obtained and these allow the production of ceramic parts, which demonstrates the feasibility of the process. Sintering at 1,580°C leads to dense ceramic parts with homogeneous microstructure. The process still needs to be optimized to improve even more the mechanical properties.

The purpose of this paper is to evaluate the mechanical properties of photopolymer/CB (carbon black) nanocomposite when applied in a visible-light rapid prototyping (RP) machine.

The mechanical properties of the samples such as hardness and tensile strength along with thermal stability were analyzed. The curing time behavior of the photopolymer/CB nanocomposites was tested by using a rigid-body pendulum rheometer. The shrinkage property and dimensional stability were also analyzed using the technique according to ASTM D2566 and ASTM D1204, respectively.

The results showed that the prototype fabricated from pristine photopolymer tended to exhibit poor mechanical properties and low thermal stability. However, after adding the photopolymer with various concentrations of nano-CB and dispersant in appropriate composition, the photopolymer/CB nanocomposite prototype not only reduced its curing time but also enhanced its mechanical properties, thermal stability and dimensional stability.

The presented results can be used in a visible-light RP machine.

The mechanical and thermal properties of photopolymer are improved with nano-CB additives for a RP system.

The purpose of this paper is to present a new ceramic suspension to fabricate complex ceramic parts by stereolithography (SL).

The process consists of preparation of aqueous ceramic suspensions, building ceramic parts, drying, subsequent binder removal, and sintering. Highly concentrated aqueous ceramic suspensions with a suitable viscosity are prepared, then a wet green ceramic part fabricated in a SL machine according to a 3D model is dried in polyethylene glycol. After binder removal sintering in a high temperature‐sintering furnace, a complex ceramic part is obtained.

The dispersant, volume fraction of ceramic powder and powder diameter could influence the viscosity of suspension. The cured depth is inversely proportional to the scanning speed of laser spot when the laser power keeps a constant and proportional to the concentration of monomer. The penetration depth and critical exposure are 0.27 mm and 231.2 mJ/cm² from the experimental result of the windowpanes method. A new support structure could prevent the deformation of ceramic part from the suspension and improve the quality of ceramic parts. A complex impeller is fabricated at last.

The dimensional and surface accuracy of ceramic SL should be further investigated.

This paper describes a new aqueous ceramic suspension to produce complex‐shaped ceramic parts by SL.

The characteristics of PZT suspensions have been studied and fit to stereolithography restraints. On one hand, researches concern the influence of fillers contents, dispersant concentration, temperature and resins nature and amount on suspensions rheological behaviour. On the other hand, the influence of photoinitiator and PZT concentrations, density of energy and nature of the resin on suspension reactivity was investigated. These experiments have led to the choice of two photosensitive suspensions suitable for stereolithography purpose; which use depend on the fillers content. Furthermore, the stereolithography process has been modified owing to the balance between suspensions rheological and photochemical properties in order to shape piezoelectric ceramics. Thanks to these improvements, PZT ceramics/polymer composites dedicated to transducers and medical imaging applications have been fabricated.

The purpose of this paper is to fabricate and characterize osteochondral beta‐tricalcium phosphate/collagen scaffold with bio‐inspired design by ceramic stereolithography (CSL) and gel casting.

Histological analysis was applied to explore the morphological characteristics of the transitional structure between the bone and the cartilage. The acquired data were used to design biomimetic biphasic scaffolds, which include the bone phase, cartilage phase, and their transitional structure. The engineered scaffolds were fabricated from β‐TCP‐collagen by CSL and gel casting. The cartilage phase was added to the ceramic phase by gel‐casting and freeze drying.

The resulting ceramic scaffolds were composed of a bone phase with the following properties: 700‐900 μm pore size, 200‐500 μm interconnected pores size, 50‐65 percent porosity, fully interconnected, ∼12 Mpa compressive strength. A suitable binding force between cartilage phase and ceramic phase was achieved by physical locking that was created by the biomimetic transitional structure. Cellular evaluation showed satisfactory results.

This study is the first try to apply CSL to fabricate biological implants with β‐TCP and type‐I collagen. There are still some defects in the composition of the slurry and the fabrication process.

This strategy of osteochondral scaffold fabrication can be implemented to construct an osteochondral complex that is similar to native tissue.

The CSL technique is highly accurate, as well as biologically secure, when fabricating ceramic tissue engineering scaffolds and may be a promising method to construct hard tissue with delicate structures. The present strategy enhances the versatility of scaffold fabrication by RP.

The purpose of this research, is to develop a nano composite deposition system (NCDS) to fabricate three dimensional functional nano composite parts.

The NCDS is a hybrid system in which material removal process by mechanical micro machining and/or the deposition process is combined.

Hybrid RP technology showed higher precision than those made by casting or deposition process. Tensile strength of the hydroxyapatite‐acrylic composite was about four times higher than that of resin‐only specimen while MWCNT composite did not show much improvement.

The paper illustrates new approaches for rapid prototyping techniques with various materials and high precision.

Conventional machining methods for fabricating piezoelectric components such as ultrasound transducer arrays are time-consuming and limited to relatively simple geometries. The purpose of this paper is to develop an additive manufacturing process based on the projection-based stereolithography process for the fabrication of functional piezoelectric devices including ultrasound transducers.

To overcome the challenges in fabricating viscous and low-photosensitive piezocomposite slurry, the authors developed a projection-based stereolithography process by integrating slurry tape-casting and a sliding motion design. Both green-part fabrication and post-processing processes were studied. A prototype system based on the new manufacturing process was developed for the fabrication of green-parts with complex shapes and small features. The challenges in the sintering process to achieve desired functionality were also discussed.

The presented additive manufacturing process can achieve relatively dense piezoelectric components (approximately 95 per cent). The related property testing results, including X-ray diffraction, scanning electron microscope, dielectric and ferroelectric properties as well as pulse-echo testing, show that the fabricated piezo-components have good potentials to be used in ultrasound transducers and other sensors/actuators.

A novel bottom-up projection system integrated with tape casting is presented to address the challenges in the piezo-composite fabrication, including small curing depth and viscous ceramic slurry recoating. Compared with other additive manufacturing processes, this method can achieve a thin recoating layer (as small as 10 μm) of piezo-composite slurry and can fabricate green parts using slurries with significantly higher solid loadings. After post processing, the fabricated piezoelectric components become dense and functional.

Barabási‐Albert and small‐world networks. In this model, the order‐disorder phase transition of the order parameter is well defined on small‐world networks. We calculate the value of the critical temperature Tc for several values of rewiring probability p of the directed small‐world network. For directed small‐world networks we obtained a second‐order phase transition for p = 0.2 and first‐order phase transition for p = 0.8. On directed Barabási‐Albert we show that phase transition do not exist for Ising model with spin S = 1, 3/2 and 2.