Micro-and Nano-electromechanical (MEM/NEM) relays can operate with zero-leakage at far higher temperatures and levels of radiation than transistors, but have poor reliability. This work demonstrates improvement in reliability of MEM relays using nano-crystalline graphite (NCG)-coated contact surfaces. The high stability of NCG in ambient air, along with its low surface energy, appear to make it an ideal contact material. NCG-coated relays achieved over 2.8 million fast, hot-switching cycles with a drain current of at least 5 µA and on-resistance under 17 kΩ, in ambient air. The relays also were tested in slow, hot-switching cycles designed to increase the electrical stress on the contact, and consistently achieved on-currents up to 50 µA or the imposed current limit without failure. The eventual cause of failure appeared to be mechanical stress on the NCG layer over repeated cycling causing degradation. Increasing the layer thickness is expected to further improve the contact reliability. The relays are scalable and can be used as micro-or nano-scale switches in electronic components designed for very high temperatures and levels of radiation.

Tubular structure and well dense of aligned carbon nanotubes (CNTs) were formulated using two-stage catalytic chemical vapor deposition apparatus. In this experiment, aligned CNT was synthesized in the range of 700–900°C temperatures with increment rate of 50°C per sample. The aligned CNT properties were investigated via field emission scanning electron microscope, micro-Raman spectrometer and thermogravimetric analyzer. The experimental results showed that aligned CNT properties were highly dependent on synthesis temperature changes. The optimum temperature of higher crystallinity was observed at 800°C synthesis temperature. However, the highest yield of nanotubes (~99.99%) was obtained at 900°C synthesis temperature. Aligned CNT orientation was in a parallel form and packed together in orderly manner. The behaviors of aligned CNT will be discussed in detail in this paper.

Carbon nanotubes have many applications and therefore widely produced. However, it is limited due to the high production cost. In this paper, by preparing the CNTs using the Thermal Chemical Vapor Deposition method, CNTs were synthesized with a low cost method since palm oil is used as the precursor which is a biodegradable and cheap source. The aerosol or spray pyrolysis method is used for single stage and double stage TCVD method. Then, the samples were both collected at deposition temperature of 750°C and were characterized using Brunauer, Emmett and Teller (BET) method. Since CNTs are said to have high surface area therefore BET method is used to prove this fact. Results showed that by using double stage TCVD method, more CNTs were synthesized compared to single stage TCVD method which produced more impurities namely amorphous carbon. CNTs also have higher surface area compared to amorphous carbon. To support this result, the images of the CNTs produced by same method but different parameters were characterized with field emission scanning electron microscope (FE-SEM) and the raman spectra was determined by the raman spectroscopy characterization.

3D metal printing and aerospace industry is an ideal combination where 3D metal printing offers unmatched advantages over the conventional method in terms of its rapid prototyping, rapid tooling, easy maintenance and repairs. With the provision and implementation of 3D metal printing onto aerospace sector, leading manufacturers are now enjoying great benefits as this exciting technology reduces the lead-time, increases production flexibility as well as cost-effective. However, we are now left with a big question: whether or not this 3D metal printing technology has arrived to its maximum capacity where the system operates with no flaw. Previous studies have shown that 3D metal printing is battling with its consistency, repeatability and traceability due to many independent variables that need to be controlled in a single run. Adoption of Artificial Intelligence onto the 3D metal printing has been viewed to be a promising step and therefore, serves as a cornerstone towards a better development of 3D metal printing technology.

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