Direct Ink Writing of Silicon Carbide for Microwave Optics

Abstract

Silicon carbide (SiC) is one of the most versatile engineering ceramic materials in existence. Its low density (r % 3.21 g cc À1 ), high flexural strength (s % 550 MPa), high Young's modulus (E % 400 GPa), high hardness (%2,800 kg mm À2 ), low thermal expansion (CTE % 4 Â 10 À6 K À1 ), high thermal conductivity (K % 400 W m À1 K À1 ), and excellent thermochemical stability make it an ideal material for friction systems and abrasives, high-temperature filters and catalyst supports, and a vast array of other hightemperature industrial processes. SiC also has unique electronic properties including a wide electronic bandgap of 2.2-3.3 eV (c.f., Si % 1.5 eV), high electric breakdown strength of 2.4 Â 10 6 MV cm À1 (c.f., Si % 0.2 Â 10 6 MV cm À1 ), and high saturation velocity of 2 Â 10 7 cm s À1 (c.f., Si % 1 Â 10 7 cm s À1 ), that make it an attractive semiconducting material for applications such as high-voltage, high-power, and high-frequency electronics (e.g., in electric vehicles, grid storage devices), DC inverters for photovoltaics, short wavelength optoelectronics, high-temperature gas sensors, and MEMS. SiC is also an important material for space-and ground-based optics, such as telescope mirrors and support structures, for which low density, high specific stiffness (E SiC / r SiC % 100-125 MN m À1 kg À1 ), and thermal insensitivity are critical. SiC is second only to beryllium in specific strength [*] Prof.

Radio Frequency and Microwave Heating of Preceramic Polymer Nanocomposites with Applications in Mold‐Free Processing

“…Recent studies have developed techniques like direct ink writing method to 3D print SiC structures using polycarbosilane inks with fillers. [6,8] These polymers are also commercially spun and converted to silicon carbide fibers, which are used as reinforcing agents in ceramic matrix composites for aircraft engine components. [9,10] In mold free processing methods like 3D printing and fiber processing, curing is an important step for retaining shape.…”

CL‐20 based Explosive Ink of Emulsion Binder System for Direct Ink Writing

“…Direct ink writing (DIW) is a low-cost, high efficiency material forming technology, which has been widely used in ceramic materials [5][6], piezoelectric materials [7], as well as novel functional materials [8] design and preparation fields. In the field of energetic materials, DIW technology has attracted more and more attentions.…”

Additive Manufacturing Review: Early Past to Current Practice

“…AM of SiC has been demonstrated from a homogenous polymer solution [220], and Ca 2 ZnSi 2 O 7 bioceramics were demonstrated using the suspension approach in which ZnO and CaCO 3 particles were added to the SiO 2 precursor as reactants [221]. The solid particles may also be also be used to produce composites structures in the final state and this approach has been used to produce ceramic matrix composites [222] and composites for applications in optics [223].…”