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The proposed work investigates a novel 3D printing technique called as Solvent based Slurry Stereolithography (3S) to fabricate membranes for filtration application. 3S process is an indirect fabrication method where the green parts are 3D printed first and densified later by sintering process. In this paper, membranes using alumina material were fabricated with a controlled thickness between 200 and 250 μm and surface roughness ranges between 0.17 and 0.18 μm. The factors that affected the entire fabrication process such as material synthesis, printing parameters, and the sintering temperature cycle are presented through empirical data. The material synthesis includes powder selection based on the morphology and optimization of the raw material. Based on the particle structure and its concentration, different slurry compositions were prepared, and green parts were 3D printed. The printed samples are characterized for thickness, roughness, porosity, and pore size followed with a brief discussion regarding filtration application.

Additive manufacturing (AM) has become a versatile and diversified technology that has made a huge difference in how things are being manufactured. Substantial growth has been observed in the development of ceramic materials for AM processes. However, ceramic parts manufactured by AM methods often exhibit deficiencies in mechanical properties and performance. Recent research developments have included improvement of performance and mechanical properties by introducing a material preparation process and additional post-processing techniques to improve the fabrication process. This paper contemplates and reviews the advancements made in AM techniques to fabricate high-performance ceramic (HPC) materials, also known as advanced ceramics. AM processes are classified as per ASTM standards and the technologies implemented are sub-listed. The principles, mechanical properties, advantages, disadvantages, applications, and limitations of each technology are described in detail.

This paper describes an efficient method of fabricating high-performance ceramic (HPC) parts by using solvent-based slurry stereolithography (3S) and sintering. In this study, zirconia was used as the structural material, methyl alcohol was used as the solvent, a waterborne inorganic pigment was used as the dispersant, and a visible-light-curing resin was used as the organic binder for forming the slurry. The slurry was photocured using a visible-light projector for layer-by-layer deposition in an enclosed cabinet to form a three-dimensional object. The obtained green part was sintered at high temperatures (up to 1600 °C) so that it densified and formed a rigid body. Thus, an HPC part with high material strength could be produced. A complete system was developed for producing complex zirconia ceramic parts with a high level of precision without the necessity of generating support structures for the overhang features. The system was determined to achieve a very fine-detailed shape (30 μm). The mechanical properties of the obtained zirconia parts, such as flexural strength, density, and average roughness, were also investigated in this study.

Membrane wetting in membrane distillation (MD) is a prominent issue during desalination operation, where the interfacial characteristics between the membrane surface and the feed stream are critical. In this study, an antiwetting membrane surface consisting of hierarchical microstructures was explored as a novel concept to understand the wetting behavior during the MD operation. A novel surface-engineered design of an antiwetting polyvinylidene fluoride (PVDF) membrane with micropatterned arrays obtained utilizing a 3D-printed molding phase separation method was thoroughly explored. In a novel introduction to this field, 3D-printed templates with micron-sized pillars in different shapes are used to generate air pockets when imprinted with a polymeric membrane. Additionally, hexadecyltrimethoxysilane was used as a chemical modifier for enhancing the hydrophobic characteristics. Membrane properties were thoroughly analyzed through Fourier-transform infrared spectroscopy, atomic force microscopy, scanning electron microscopy coupled with energy-dispersive X‐ray spectroscopy, and X-ray photoelectron spectroscopy after successful fabrication of the surface and chemically engineered membrane. The chemically modified patterned membrane exhibited a higher contact angle of ~140° and superior antiwetting behavior when compared to that of the plain PVDF membrane. Moreover, the engineered membrane showed superior MD performance in terms of salt rejection and water flux. Therefore, this paper demonstrates a simplistic approach to design a micropatterned functional membrane exhibiting antiwetting and self-cleaning behavior during MD operation.

This paper discusses the development of a complete turnkey system to measure, design, and manufacture customized insoles. An optical foot measuring technology has been developed and used to detect the dimensions as well as the plantar pressure distribution of the foot pair instantly. A 3D CAD model of the insole is automatically generated followed by simple adjustments based on a certified medical professional’s diagnosis. The generated pair of customized insole models are joined together by their edges to form a single piece for easy manufacturing and easily separable once fabricated. The fabrication is done by Material Extrusion (ME) process using PETG (a modified version of PET) material in a custom built machine. In this paper, it is discussed in detail about the Foot Measurement Apparatus (FMA), Design approach, and Fabrication using Additive Manufacturing (AM) process.