Micro-Machining of Diamond, Sapphire and Fused Silica Glass Using a Pulsed Nano-Second Nd:YVO4 Laser

Optically transparent materials are being found in an ever-increasing array of technological applications within industries, such as automotive and communications. These industries are beginning to realize the importance of implementing surface engineering techniques to enhance the surface properties of materials. On account of the importance of surface engineering, this paper details the use of a relatively inexpensive diode-pumped solid state (DPSS) Nd:YVO4 laser to modify the surfaces of fused silica glass, diamond, and sapphire on a micrometre scale. Using threshold fluence analysis, it was identified that, for this particular laser system, the threshold fluence for diamond and sapphire ranged between 10 Jcm−2 and 35 Jcm−2 for a laser wavelength of 355 nm, dependent on the cumulative effects arising from the number of incident pulses. Through optical microscopy and scanning electron microscopy, it was found that the quality of processing resulting from the Nd:YVO4 laser varied with each of the materials. For fused silica glass, considerable cracking and deformation occurred. For sapphire, good quality features were produced, albeit with the formation of debris, indicating the requirement for post-processing to remove the observed debris. The diamond material gave rise to the best quality results, with extremely well defined micrometre features and minimal debris formation, comparative to alternative techniques such as femtosecond laser surface engineering.

Generating and storing power on the moon using in situ resources

The Moon Village and similar concepts are strongly reliant on in situ resource utilisation (ISRU). There is great interest in harvesting solar power using locally leveraged in situ resources as an essential facet of in situ infrastructure. Traditionally, silicon-based photovoltaic cells have been assumed, preferably manufactured in situ using a 3D printing rover, but there are major difficulties with such scenarios. Solar cells require pre-processing of regolith and solar cell manufacture. We present an alternative lunar resource leveraged-solar power production system on the Moon which can yield high conversion efficiencies – solar Fresnel lens-thermionic conversion. The thermionic vacuum tube is constructed from lunar-derived materials and NiFe asteroidal ores on the Moon. Given that the majority of energy required for ISRU is thermal, thermionic conversion exploits this energy source directly. Silicates such as anorthite can be treated with acid to yield alumina and silicic acid in solution from which pure silica can be precipitated. Pure silica when heated to high temperature yields fused silica glass which is transparent – fused silica glass may be employed to manufacture Fresnel lenses and/or mirrors. Both silica and alumina may be input to the Metalysis Fray Farthing Chen Cambridge electrolytic process to yield near pure Si and near pure Al, respectively.

The Analysis and Simulation with the Fatigue Life of Hemispherical Resonator Gyro

The life and damage of hemispherical resonator are important factors that directly affect the service time and safety of high-precision hemispherical resonator gyro. However, the fused silica glass material used in the hemispherical resonator which was processed in China is mainly imported, and it is too expensive to use the traditional fatigue life experiment, so it is necessary to use the software of fatigue life analysis to analyze its fatigue life. In the paper, the ANSYS software is used to analyze the fatigue life of fused silica hemispherical resonator, to determine the dangerous parts caused by the residual stress to analyze the crack propagation in the fatigue parts, and to obtain the sum stress intensity factor, so as to effectively monitor and prevent the fatigue-prone parts in the process of structural design and use of the hemispherical resonator.

High-throughput injection molding of transparent fused silica glass

Glass is one of the most relevant high-performance materials that has the benefit of a favorable environmental footprint compared with that of other commodity materials. Despite the advantageous properties of glasses, polymers are often favored because they can be processed using scalable industrial replication techniques like injection molding (IM). Glasses are generally processed through melting, which is both energy intensive and technologically challenging. We present a process for glassworks using high-throughput IM of an amorphous silicon dioxide nanocomposite that combines established process technologies and low-energy sintering. We produce highly transparent glass using classical IM and sintering, allowing for a potentially substantial reduction in energy consumption. Our strategy merges polymer and glass processing, with substantial implications for glass utilization.