3D printing of lunar bases using moondust

An investigation into using Selective Laser Melting (SLM), a modern powder-bed fusion category Additive Manufacturing/3D printing process, in order to fabricate structures out of non-traditional multi-component ceramic materials such as lunar regolith (moondust). The overall aim of this research is to investigate the feasibility/suitability of the SLM method for on-site (on the moon) manufacturing of various structures, parts/replacements for future space applications

3D printing with moondust

Purpose – The purpose of this paper is to investigate the effect of the main process parameters of Laser Melting (LM) type Additive Manufacturing (AM) on multi layered structures manufactured from JSC-1A Lunar regolith (Moondust) simulant powder. Design/methodology/approach – Laser diffraction technology was used to analyse and confirm the simulant powder material particle sizes and distribution. Geometrical shapes were then manufactured on a Realizer SLM™ 100 using the simulant powder. The laser-processed samples were analysed via Scanning Electron Microscopy (SEM) to evaluate surface and internal morphologies, Energy-dispersive X-ray Spectroscopy (EDS) to analyse the chemical composition after processing and the samples were mechanically investigated via Vickers micro-hardness testing. Findings – A combination of process parameters resulting in an energy density value of 1.011 J/mm2 allowed the successful production of components directly from Lunar regolith simulant. An internal relative porosity of 40.8 %, material hardness of 670 ± 11 HV and a dimensional accuracy of 99.8 % were observed in the fabricated samples. Originality/value – This research paper is investigating the novel application of a Powder Bed Fusion AM process category as a potential on-site manufacturing approach for manufacturing structures/components out of Lunar regolith (Moondust). It was shown that this AM process category has the capability to directly manufacture multi-layered parts out of Lunar regolith, which has potential applicability to future moon colonization

Additive manufacturing using extra-terrestrial multi-component ceramic materials

Powder Bed Fusion (PBF) based Additive Manufacturing (AM) is a category of advanced manufacturing technologies that can fabricate three-dimensional assets directly from CAD data, on a successive layer-by-layer strategy by using thermal energy from a laser source, to irradiate and fuse particles on a powder bed. The aim of this research was to investigate the application of this advanced manufacturing technique to laser process ceramic multicomponent materials into 3D layered structures. These ceramic materials matched those found on the Lunar and/or Martian surface. These indigenous extra-terrestrial materials could potentially be used for manufacturing physical assets onsite (i.e. off World) on future planetary exploration missions and could cover a range of potential applications including infrastructure, radiation shielding, thermal storage, etc. JSC-1A Lunar and JSC-Mars-1A Martian soil simulants, mimicking the mineralogical and basic properties of these planetary indigenous materials were used for the purpose of this study and processed with commercially available laser additive manufacturing equipment. The results of the laser processing were investigated and quantified through mechanical hardness testing, optical and scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDS). The research resulted in the identification of a range of parameters that resulted in the successful manufacture of three-dimensional components from Lunar and Martian ceramic multicomponent simulant materials. The feasibility of using thermal based additive manufacturing with multi-component ceramic materials has therefore been established which represents a potential solution to off-world bulk structure manufacture due to there being no requirement for additional materials and resources other than the manufacturing equipment to be shipped off-world

Additive manufacturing of physical assets by using ceramic multicomponent extra-terrestrial materials

Powder Bed Fusion (PBF) is a range of advanced manufacturing technologies that can fabricate three-dimensional assets directly from CAD data, on a successive layer-by-layer strategy by using thermal energy, typically from a laser source, to irradiate and fuse particles within a powder bed.The aim of this paper was to investigate the application of this advanced manufacturing technique to process ceramic multicomponent materials into 3D layered structures. The materials used matched those found on the Lunar and Martian surfaces. The indigenous extra-terrestrial Lunar and Martian materials could potentially be used for manufacturing physical assets onsite (i.e., off-world) on future planetary exploration missions and could cover a range of potential applications including: infrastructure, radiation shielding, thermal storage, etc.Two different simulants of the mineralogical and basic properties of Lunar and Martian indigenous materials were used for the purpose of this study and processed with commercially available laser additive manufacturing equipment. The results of the laser processing were investigated and quantified through mechanical hardness testing, optical and scanning electron microscopy, X-ray fluorescence spectroscopy, thermo-gravimetric analysis, spectrometry, and finally X-ray diffraction.The research resulted in the identification of a range of process parameters that resulted in the successful manufacture of three-dimensional components from Lunar and Martian ceramic multicomponent simulant materials. The feasibility of using thermal based additive manufacturing with multi-component ceramic materials has therefore been established, which represents a potential solution to off-world bulk structure manufacture for future human space exploration

The effect of print speed and material aging on the mechanical properties of a self-healing nanocomposite hydrogel

A UV-curable nanoclay-zwitterionic hydrogel is synthesised and evaluated though rheological and mechanical testing. The result shows that aging time of the pre-gel have a big impact on storage and loss of modulus which both increases with increasing aging time, particularly in the first 48 h. The pre-gel is successfully printed and is shown to be able to support itself making it possible to fully print structures before curing. Compression and tensile samples are printed and compared to cast samples. The pre-gel aging time showed that an increased time resulted in a lower strain at failure for both casted and extruded samples. However, when printing with a speed of 10 mm/s with UV-curing during printing, a significant increase in strain at failure is achieved. Furthermore, the compressed samples display self-healing abilities at room temperature and almost completely returns to its original state before compression occurred

Assessing extraterrestrial regolith material simulants for in-situ resource utilization based 3D printing

This research paper investigates the suitability of ceramic multicomponent materials, which are found on the Martian and Lunar surfaces, for 3D printing (aka Additive Manufacturing) of solid structures. 3D printing is a promising solution as part of the cutting edge field of future in‐situ space manufacturing applications. 3D printing of physical assets from simulated Martian and Lunar regolith was successfully performed during this work by utilising laser‐based powder bed fusion equipment. Extensive evaluation of the raw regolith simulants was conducted via Optical and Electron Microscopy (SEM), Visible‐Near Infrared/Infrared (Vis‐NIR/IR) Spectroscopy and thermal characterisation via Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The analysis results led to the characterisation of key properties of these multicomponent ceramic materials with regards to their processability via powder bed fusion 3D printing. The Lunar and Martian simulant regolith analogues demonstrated spectral absorbance values of up to 92% within the Vis‐NIR spectra. Thermal analysis demonstrated that these materials respond very differently to laser processing, with a high volatility (30% weight change) for the Martian analogue as opposed to its less volatile Lunar counterpart (<1% weight change). Results also showed a range of multiple thermal occurrences associated with melting, glass transition and crystallisation reactions. The morphological features of the powder particles are identified as contributing to densification limitations for powder bed fusion processing. This investigation has shown that – provided that the simulants are good matches for the actual regoliths – the lunar material is a viable candidate material for powder bed fusion 3D printing, whereas Martian regolith is not

3D printing with extraterrestrial materials

Additive manufacturing and its related powder bed fusion process category, consists of a group of key enabling technologies that allow the fabrication of various structures (...continues)

Mechanical behaviour of additively manufactured lunar regolith simulant components

Additive manufacturing and its related techniques have frequently been put forward as a promising candidate for planetary in-situ manufacturing, from building life-sustaining habitats on the Moon to fabricating various replacements parts, aiming to support future extra-terrestrial human activity. This paper investigates the mechanical behaviour of lunar regolith simulant material components, which is a potential future space engineering material, manufactured by a laser-based powder bed fusion additive manufacturing system. The influence of laser energy input during processing was associated with the evolution of component porosity, measured via optical and scanning electron microscopy in combination with gas expansion pycnometry. The compressive strength performance and Vickers microhardness of the components were analysed and related back to the processing history and resultant microstructure of the lunar regolith simulant build material. Fabricated structures exhibited a relative porosity of 44 – 49% and densities ranging from 1.76 – 2.3 g cm-3, with a maximum compressive strength of 4.2 ± 0.1 MPa and elastic modulus of 287.3 ± 6.6 MPa, the former is comparable to a typical masonry clay brick (3.5 MPa). The 2AM parts also had an average hardness value of 657 ± 14 HV0.05/15, better than borosilicate glass (580 HV). This study has shed significant insight into realizing the potential of a laser-based powder bed fusion AM process to deliver functional engineering assets via in-situ and abundant material sources that can be potentially used for future engineering applications in aerospace and astronautics

Public perceptions of household IoT smart water ‘event’ meters in the UK – implications for urban water governance

Cities around the world are facing water availability challenges, intensified by increasing populations and climate change. Technology, such as household smart meters measuring domestic water consumption, can play a role in demand management, yet a deeper understanding of public expectations and the practicalities of city-wide implementation is required. This article explores public perceptions of smart water meters that use Internet of Things (IoT) technology and machine learning to profile household water use “events” and anomalies. By leveraging insights from an online survey implemented in the UK (n = 558), this article explores factors influencing the likelihood of citizens choosing to have this type of meter installed along with potential societal barriers and opportunities. Nearly half of the participants said they would choose to have such a meter installed and logistic regression showed predictive variables were younger ages, being male, those with existing water meters and those with other smart devices. The likelihood of choosing this type of water meter was also associated with preferences to have control over data privacy, whether the meter would reduce water bills and whether it was provided free of charge. We locate these results within other contemporary experiences of smart meters and water grids in urban contexts to discuss practical challenges of using real-time environmental data for urban water governance. Policymakers and water resources planners should continue to monitor public perceptions, implement urban experiments and cost-benefit analyses to better interpret the wider benefits of such technology for behavioral and educational interventions within a more digitized and increasingly data-centric water grid.Creative E

Mechanical behaviour of additively manufactured lunar regolith simulant components

Additive manufacturing and its related techniques have frequently been put forward as a promising candidate for planetary in-situ manufacturing, from building life-sustaining habitats on the Moon to fabricating various replacements parts, aiming to support future extra-terrestrial human activity. This paper investigates the mechanical behaviour of lunar regolith simulant material components, which is a potential future space engineering material, manufactured by a laser-based powder bed fusion additive manufacturing system. The influence of laser energy input during processing was associated with the evolution of component porosity, measured via optical and scanning electron microscopy in combination with gas expansion pycnometry. The compressive strength performance and Vickers microhardness of the components were analysed and related back to the processing history and resultant microstructure of the lunar regolith simulant build material. Fabricated structures exhibited a relative porosity of 44 – 49% and densities ranging from 1.76 – 2.3 g cm-3 , with a maximum compressive strength of 4.2 ± 0.1 MPa and elastic modulus of 287.3 ± 6.6 MPa, the former is comparable to a typical masonry clay brick (3.5 MPa). The 2 AM parts also had an average hardness value of 657 ± 14 HV0.05/15, better than borosilicate glass (580 HV). This study has shed significant insight into realizing the potential of a laser-based powder bed fusion AM process to deliver functional engineering assets via in-situ and abundant material sources that can be potentially used for future engineering applications in aerospace and astronautics