Faculty of Design and Creative Technologies (Te Ara Auaha)

Permanent link for this community

https://hdl.handle.net/10292/10758
The Faculty of Design and Creative Technologies - Te Ara Auaha is comprised of four schools: The School of Future Environments - Huri Te Ao, the School of Art and Design - Te Kura Toi a Hoahoa, the School of Communication Studies - Te Kura Whakapāho and the School of Engineering, Computer and Mathematical Sciences - Te Kura Mātai Pūhanga, Rorohiko, Pāngarau. It also has Institutes, Centres and Labs across the Arts and Sciences in a mix that blends the traditional and the new, praxis and theory.

Browse

Browsing Faculty of Design and Creative Technologies (Te Ara Auaha) by Subject "03 Chemical Sciences"

Now showing 1 - 9 of 9
  • Item
    Biocompatible Polymer for Self-Humidification
    (MDPI AG, 2023-10-16) Al-Jumaily, Ahmed M; Bartual, Sandra; Weerasinghe, NT
    Lung supportive devices (LSDs) have been extensively utilized in treating patients diagnosed with various respiratory disorders. However, these devices can cause moisture depletion in the upper airway by interfering with the natural lubrication and air conditioning process. To remedy this, current technologies implement heated humidification processes, which are bulky, costly, and nonfriendly. However, it has been demonstrated that in a breath cycle, the amount of water vapor in the exhaled air is of a similar quantity to the amount needed to humidify the inhaled air. This research proposes to trap the moisture from exhaled air and reuse it during inhalation by developing a state-of-the-art hydrophilic/hydrophobic polymer tuned to deliver this purpose. Using the atom transfer radical polymerization (ATRP) method, a substrate was successfully created by incorporating poly (N-isopropyl acrylamide) (PNIPAM) onto cotton. The fabricated material exhibited a water vapor release rate of 24.2 ± 1.054%/min at 32 °C, indicating its ability to humidify the inhaled air effectively. These findings highlight the potential of the developed material as a promising solution for applications requiring rapid moisture recovery.
  • Item
    Improved Performance in Temperature and Speed of TCP Artificial Muscles for Soft Wearables Robots by Length Modification
    (IOP Publishing, 2023-06-15) Gonzalez, Alberto; Garcia, Lorenzo; Kilby, Jeff
    Artificial muscles provide a unique solution for wearable rehabilitation robots (WRRs) because they are compliant, compact, and lightweight. Twisted and coiled polymer actuators (TCPs) are artificial muscles from thermally activated polymer fibres. They present high power density, linearity, stress and strain compared to other artificial muscles. Nevertheless, as TCPs require heat to start, their main barrier for widespread use in WRRs are their slow reaction times and the high temperatures they reach. Previous studies have analysed different parameters, like fibre material, fibre diameter, and various cooling systems, to improve TCP frequency response and working temperature. Nevertheless, the length of the actuator has not been explored as a possible parameter to enhance the actuation performance in this regard.

 This work focuses on studying the behaviour of TCPs with different lengths and how the performance in frequency response and temperature can be improved using the length as a primary parameter, as they are critical for wearable robots. First, a characterisation of the TCPs was performed. Then, a method to improve frequency response, based on offsets on long actuators was implemented and validated using a chirp signal. The experimental results show that the mechanical characteristics are similar regardless of the actuator’s length. They reached a strain of 10 % with a power of 0.16 W/cm. However, the electrothermal properties changed as the power needed to increase temperature was higher when the actuator was enlarged. Therefore, an improvement in the required temperature was found, able to reduce the temperature with the same frequency response. Regarding the technique to enhance the speed of the actuator, it was possible to increase the frequency by 0.0006 Hz for each mm applied as an offset. Hence, the frequency response for the same displacement was increased linearly as the actuator was elongated.
  • Item
    Laser Powder Bed Fusion of Inconel 718 Tools for Cold Deep Drawing Applications: Optimization of Printing and Post-processing Parameters
    (MDPI AG, 2023-06-29) Jiang, Cho-Pei; Maidhah, Andi Ard; Wang, Shun-Hsien; Wang, Yuh-Ru; Pasang, Tim; Ramezani, Maziar
    Inconel 718 (IN 718) powder is used for a laser powder bed fusion (LPBF) printer, but the mechanical properties of the as-built object are not suited to cold deep drawing applications. This study uses the Taguchi method to design experimental groups to determine the effect of various factors on the mechanical properties of as-built objects produced using an LPBF printer. The optimal printing parameters are defined using the result for the factor response to produce an as-built object with the greatest ultimate tensile strength (UTS), and this is used to produce a specimen for post-processing, including heat treatment (HT) and surface finishing. The HT parameter value that gives the maximum UTS is the optimal HT parameter. The optimal printing and HT parameter values are used to manufacture a die and a punch to verify the suitability of the manufactured tool for deep drawing applications. The experimental results show that the greatest UTS is 1091.33 MPa. The optimal printing parameters include a laser power of 190 W, a scanning speed of 600 mm/s, a hatch space of 0.105 mm and a layer thickness of 40 μm, which give a UTS of 1122.88 MPa. The UTS for the post-processed specimen increases to 1511.9 MPa. The optimal parameter values for HT are heating to 720 °C and maintaining this temperature for 8 h, decreasing the temperature to 620 °C and maintaining this temperature for 8 h, and cooling to room temperature in the furnace. Surface finishing increases the hardness to HRC 55. Tools, including a punch and a die, are manufactured using these optimized parameter values. The deep drawing experiment demonstrates that the manufactured tools that are produced using these values form a round cup of Aluminum alloy 6061. The parameter values that are defined can be used to manufacture IN 718 tools with a UTS of more than 1500 MPa and a hardness of more than 50 HRC, so these tools are suited to cold deep drawing specifications.
  • Item
    Pilot Study Investigating Effects of Changing Process Variables on Elastic and Energy-Absorbing Characteristics in Polyurethane/Agglomerated Cork Mix for Use in Micro-Transport Helmet
    (MDPI AG, 2024-04-22) White, David E; Kim, Hyun Chan; Al-Rawi, Mohammad; Yuan, Xiaowen; Sojan, Tony
    This pilot investigation identifies the influence that changing the process variables of curing pressure, curing temperature, and mix ratio of a polyurethane/agglomerated cork matrix has on the mechanical properties of energy absorption, Young's modulus of elasticity, and spring stiffness in safety helmets intended for micro-transport riders. The results are compared to expanded polystyrene, a material commonly used in micro-transport helmets. Mechanical testing of the various samples found that, over the range tested, curing pressure had no effect on any of the mechanical properties, while increasing amounts of resin caused a stiffer structure, and increasing curing temperature led to increased energy absorption. Consistent with the elastic modulus findings, all polyurethane/agglomerated cork test samples demonstrated higher median levels of spring stiffness, ranging from 7.1% to 61.9% greater than those found for expanded polystyrene. The sample mixed at a 1.5:1 binder/cork ratio and cured at 40 °C displayed the closest spring stiffness to EPS. While the mechanical properties of the eco-friendly polyurethane/agglomerated cork matrix did not match those of expanded polystyrene, the difference in performance found in this study is promising. Further investigation into process variables could characterise this more ecologically based matrix with equivalent energy-absorbing and structural characteristics, making it equivalent to currently used expanded polystyrene and suitable for use in micro-transport helmets.
  • Item
    Potential of Bacterial Cellulose for Sustainable Fashion and Textile Applications: A Review
    (Springer Science and Business Media LLC, 2024-04-10) Nayak, R; Cleveland, D; Tran, G; Joseph, F
    The fashion and textile manufacturing sectors are increasingly focusing on innovative raw materials that are renewable and biodegradable. Such materials not only mitigate environmental impacts but also prevent resource depletion. Bacterial cellulose (BC) has emerged as a prime candidate, derivable from a variety of natural ingredients such as tea and coffee in addition to a sugar source in presence of the bacterial microorganisms. Numerous studies have established the potential of BC in future fashion, and some brands have already started to utilise BC as a sustainable raw material. The applications of BC ranges from basic clothing and accessories to wearable electronics. This paper discusses the scope of BC in fashion and textiles, positioning it as a sustainable alternative to conventional materials. We present a comprehensive scoping review, covering the unique properties of BC, the factors influencing its production, and its applications in textile, clothing, and footwear over the past decade. The advantages of BC in fashion are manifold: zero-waste manufacturing, reliance on renewable sources, diminished environmental pollution, and biodegradability. Furthermore, the use of BC aligns with United Nations Sustainable Development Goals 6, 7, 12, 13 and 15. However, there exist challenges pertaining to production costs, scalability, and quality, in addition to the imperative of harnessing food waste streams instead of contending for human food resources. Addressing these challenges is vital to cement BC’s position as a pivotal sustainable material in future fashion.
  • Item
    Superhydrophobic, Magnetic Aerogels Based on Nanocellulose Fibers Derived from Harakeke for Oily Wastewater Remediation
    (MDPI, 2023-09-29) Zhai, Y; Yuan, X
    Cellulose-based aerogels have been seen as a promising sorbent for oil and organic pollutant cleaning; however, their intrinsic hydrophilicity and difficulty of recycling has hindered their practical application. In this work, a superhydrophobic, magnetic cellulose-based aerogel was fabricated as a highly efficient sorbent for the adsorption of oils and organic solvents. The aerogel was prepared via a simple freeze-drying method, followed by chemical vapor deposition (CVD). The incorporation of Fe3O4 nanoparticles into the aerogel not only makes it responsive to external magnetic field, but also contributes to the better hydrophobicity of the aerogel, in which the water contact angle (WCA) was about 20° higher than the aerogel without loading with Fe3O4 nanoparticles. The adsorption test showed that the resultant aerogel can selectively adsorb a wide range of oils and organic solvents from oil/water mixtures with a high adsorption capacity (up to 113.49 g/g for silicone oil). It can retain about 50% of its adsorption capacity even after 10 adsorption–squeezing cycles, which indicates its outstanding reusability. Moreover, the aerogels can be easily controlled by an external magnet, which is preferred for the adsorption of oily contaminants in harsh environments and enhanced the recyclability of the aerogel. We believe that this study provides a green and convenient approach for the practical fabrication of cellulose-based oil sorbents.
  • Item
    Superlubricity of Materials: Progress, Potential, and Challenges
    (MDPI AG, 2023-07-21) Ramezani, Maziar; Ripin, Zaidi Mohd; Jiang, Cho-Pei; Pasang, Tim
    This review paper provides a comprehensive overview of the phenomenon of superlubricity, its associated material characteristics, and its potential applications. Superlubricity, the state of near-zero friction between two surfaces, presents significant potential for enhancing the efficiency of mechanical systems, thus attracting significant attention in both academic and industrial realms. We explore the atomic/molecular structures that enable this characteristic and discuss notable superlubric materials, including graphite, diamond-like carbon, and advanced engineering composites. The review further elaborates on the methods of achieving superlubricity at both nanoscale and macroscale levels, highlighting the influence of environmental conditions. We also discuss superlubricity's applications, ranging from mechanical systems to energy conservation and biomedical applications. Despite the promising potential, the realization of superlubricity is laden with challenges. We address these technical difficulties, specifically those related to achieving and maintaining superlubricity, and the issues encountered in scaling up for industrial applications. The paper also underscores the sustainability concerns associated with superlubricity and proposes potential solutions. We conclude with a discussion of the possible future research directions and the impact of technological innovations in this field. This review thus provides a valuable resource for researchers and industry professionals engaged in the development and application of superlubric materials.
  • Item
    Tribological Performance of Bamboo Fabric Reinforced Epoxy Composites
    (Wiley, 2023-05-28) Oliver, BA; Dong, Q; Ramezani, M; Selles, MA; Sanchez-Caballero, S
    Bamboo fiber is one of the strongest natural fibers with high strength-to-weight and stiffness-to-weight ratios and can be used economically for manufacturing fiber-reinforced composites. In this paper, bamboo fabric-reinforced epoxy composite is manufactured and its tribological properties for load-bearing applications are investigated. Sliding wear tests are conducted using a linear reciprocating tribometer and the effect of dry and lubricated contact conditions, applied load, sliding speed, temperature, and woven fabric direction on the coefficient of friction and wear rate are investigated. A scanning electron microscope is used to define the wear mechanisms at room and elevated temperatures. It is observed that the fabric orientation influences the mechanical and tribological performances of the composite material. Wear rate increases at higher loads and working temperatures; however, the effect of sliding speed is not remarkable, especially under lubricated contact conditions. The results present in this paper can be used for designing bamboo-reinforced epoxy composites for load-bearing applications, under different working conditions.
  • Item
    Weldability and Mechanical Properties of Pure Copper Foils Welded by Blue Diode Laser.
    (MDPI AG, 2024-05-02) Pasang, Tim; Fujio, Shumpei; Lin, Pai-Chen; Tao, Yuan; Sudo, Mao; Kuendig, Travis; Sato, Yuji; Tsukamoto, Masahiro
    The need to manufacture components out of copper is significantly increasing, particularly in the solar technology, semiconductor, and electric vehicle sectors. In the past few decades, infrared laser (IR) and green laser (GL) have been the primary technologies used to address this demand, especially for small or thin components. However, with the increased demand for energy saving, alternative joint techniques such as blue diode laser (BDL) are being actively explored. In this paper, bead-on-plate welding experiments on 0.2 mm thick pure copper samples employing a BDL are presented. Two sets of parameters were carefully selected in this investigation, namely Cu-1: Power (P) = 200 W; Speed (s) = 1 mm/s; and angle = 0°, and Cu-2: P = 200 W; s = 5 mm/s; and angle = 10°. The results from both sets of parameters produced defect-free full penetration welds. Hardness test results indicated relatively softer weld zones compared with the base metal. Tensile test samples fractured in the weld zones. Overall, the samples welded with Cu-1 parameters showed better mechanical properties, such as strength and elongation, than those welded with the Cu-2 parameters. The tensile strength and elongation obtained from Cu-1 were marginally lower than those of the unwelded pure copper. The outcomes from this research provide an alternative welding technique that is able to produce reliable, strong, and precise joints, particularly for small and thin components, which can be very challenging to produce.
Items in these collections are protected by the Copyright Act 1994 (New Zealand). These works may be consulted by you, provided you comply with the provisions of the Act and the following conditions of use:
  • Any use you make of these works must be for research or private study purposes only, and you may not make them available to any other person.
  • Authors control the copyright of their works. You will recognise the author’s right to be identified as the author of the work, and due acknowledgement will be made to the author where appropriate.
  • You will obtain the author’s permission before publishing any material from the work.