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The successful development of renewable feedstocks for monomer and oligomer synthesis has remained limited in its achievable biobased content, and often still rely on toxic compounds for functionalisation (e.g., acrylates). As such, the viability of itaconic acid as an abundant, cheap, and highly sustainable source of functionalisation for free radical polymerisation was explored to overcome these issues. Itaconic acid presented itself as a versatile α,β-unsaturated carbonyl diacid with the ability to be incorporated into monomers via several facile and sustainable synthesis pathways. Owing to these attributes, a novel monomer system composed of an unsaturated polyester oligomer and a castor oil derived monomer were developed and used alongside isobornyl methacrylate as a commercially available biobased reactive diluent for additive manufacturing. This system was demonstrated as an effective combination to achieve tailorable resins for masked stereolithography additive manufacturing with desirable mechanical properties, whilst maintaining a high sustainability.

This study aims to develop parameters that minimize porosity in SS316 using a Design of Experiments approach (DOE). Employing the D- Optimal (D-Optimal) method and ANOVA, we determined a quadratic model for predicting porosity. The model was validated through three-point predictions, demonstrating high accuracy. The study utilised the bootstrapping method to identify the minimum sample size required for reliable predictions, establishing that 15 samples are sufficient. This was verified by plotting three sets of 15 random samples, where actual vs. predicted values showed strong agreement. The study achieved the highest density of 7.94 g/cm³, corresponding to 99.6% relative density. These findings offer a robust framework for optimising material properties to reduce porosity effectively.

The development of fabricating in vitro flow phantoms to study biomedical fluid dynamics using laser particle image velocimetry provides a basis for better understanding and treatment of medical conditions such as aneurysms and cardiovascular disease. Additionally, the ability to fabricate patient-specific models rapidly and reliably is of interest for both bespoke therapeutic capabilities and computational modelling. Additive manufacturing (AM) presents a method for rapid and facile direct fabrication with the capability for excellent geometric and resolution fidelity that can overcome the shortcomings of traditional casting techniques. Furthermore, masked stereolithography (mSLA) presents itself as an accessible and versatile AM technology with the potential to overcome limitations seen for other AM technologies. As such, this study aimed to demonstrate mSLA as an accessible and effective AM technology for the fabrication of mechanically tailorable soft polymers for flow phantom applications.

This study examined the influence of process parameters on porosity and mechanical properties in Laser Powder Bed Fusion (LPBF) of Beta 21S (Ti–15Mo–3Nb–3Al–0.2Si) and Ti5553 (Ti-5Al-5V-5Mo-3Cr) titanium alloys, with Ti64 (Ti-6Al-4V) as the reference material. Using the volumetric energy density – a function of laser power, scan speed, hatch spacing, and layer thickness – to inform the design space, a means to achieve optimal process parameters which minimise porosity content was explored. By employing a constrained design space and response surface methodology, windows of process parameters were identified. Regression models developed for predicting porosity achieved R-squared values of 0.822 for Ti64, 0.859 for Beta 21S, and 0.788 for Ti5553, indicating strong data fit. The model for Ti64 was validated against five literature sources, with four predictions falling within confidence bands and showing an error range of 0.07 to 0.48%. For Beta 21S and Ti5553, the combined error range for validation samples was 0.24 to 0.45%. Optimal volumetric energy density parameters were suggested to maximise relative density. Vickers hardness was assessed and compared favourably to existing literature. Significant variation was found amongst hardness data, suggesting that LPBF parameters influence mechanical performance. Further investigation is recommended to understand the effects of thermal history on the observed hardness behaviour.