Additive manufacturing (AM) technology has been researched and developed for more than 20 years. Rather than removing materials, AM processes make three-dimensional parts directly from CAD models by adding materials layer by layer, offering the beneficial ability to build parts with geometric and material complexities that could not be produced by subtractive manufacturing processes. Through intensive research over the past two decades, significant progress has been made in the development and commercialization of new and innovative AM processes, as well as numerous practical applications in aerospace, automotive, biomedical, energy and other fields. This paper reviews the main processes, materials and applications of the current AM technology and presents future research needs for this technology.

Additive manufacturing: technology, applications and research needs

New microproducts need the utilization of a diversity of materials and have complicated three-dimensional (3D) microstructures with high aspect ratios. To date, many micromanufacturing processes have been developed but specific class of such processes are applicable for fabrication of functional and true 3D microcomponents/assemblies. The aptitude to process a broad range of materials and the ability to fabricate functional and geometrically complicated 3D microstructures provides the additive manufacturing (AM) processes some profits over traditional methods, such as lithography-based or micromachining approaches investigated widely in the past. In this paper, 3D micro-AM processes have been classified into three main groups, including scalable micro-AM systems, 3D direct writing, and hybrid processes, and the key processes have been reviewed comprehensively. Principle and recent progress of each 3D micro-AM process has been described, and the advantages and disadvantages of each process have been presented.

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A review on 3D micro-additive manufacturing technologies

This paper offers a review of present achievements in the field of processing of ceramic-based materials with complex geometry using the main additive manufacturing (AM) technologies In AM, the geometrical design of a desired ceramic-based component is combined with the materials design In this way, the fabrication times and the product costs of ceramic-based parts with required properties can be substantially reduced However, dimensional accuracy and surface finish still remain crucial features in today's AM due to the layer-by-layer formation of the parts In spite of the fact that significant progress has been made in the development of feedstock materials, the most difficult limitations for AM technologies are the restrictions set by material selection for each AM method and aspects considering the inner architectural design of the manufactured parts Hence, any future progress in the field of AM should be based on the improvement of the existing technologies or, alternatively, the development of new approaches with an emphasis on parts allowing the near-net formation of ceramic structures, while optimizing the design of new materials and of the part architecture

Additive Manufacturing of Ceramic‐Based Materials

Additive manufacturing of biomaterials.

In recent years, additive manufacturing, also known as three-dimensional (3D) printing, has emerged as an environmentally friendly green manufacturing technology which brings great benefits, such as energy saving, less material consumption, and efficient production. These advantages are attributed to the successive material deposition at designated target areas by delivering the energy on it. In this regard, lasers are the most effective energy source in additive manufacturing since the laser beam can transfer a large amount of energy into micro-scale focal region instantaneously to solidify or cure materials in air, therefore enabling high-precision and high-throughput manufacturing for a wide range of materials. In this paper, we introduce laser-based additive manufacturing methods and review the types of lasers widely used in 3D printing machines. Important laser parameters relevant to additive manufacturing will be analyzed and general guidelines for selecting suitable lasers for additive manufacturing will be provided. Discussion on future prospects of laser technologies for additive manufacturing will be finally covered.

Lasers in additive manufacturing: A review

Dust explosions: CFD modeling as a tool to characterize the relevant parameters of the dust dispersion

Dust explosions: How should the influence of humidity be taken into account?

The study of the rheological behaviour of PZT suspensions is essential to a better understanding of piezocomposites fabrication through stereolithography process. Research concerns the influence of fillers contents, surfactant doses, temperature and resin nature on suspensions rheological behaviour. They have led to the choice of two photosensitive suspensions suitable for stereolithography purpose; which use depends 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.

Rheological properties of PZT suspensions for stereolithography

Ignition sensitivity of gas–vapor/dust hybrid mixtures

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.

Olivier Dufaud

Papers

Dust explosions: CFD modeling as a tool to characterize the relevant parameters of the dust dispersion

Dust explosions: How should the influence of humidity be taken into account?

Rheological properties of PZT suspensions for stereolithography

Ignition sensitivity of gas–vapor/dust hybrid mixtures

Stereolithography of PZT ceramic suspensions