Materiom is an online initiative that has been growing an online open source database of bio-based material recipes over the last couple of years. A new category of recipes to be found on this website is the category of bio-based 3D printable materials. The first 3D printable material recipe to emerge in the database was developed at the TU Delft. Since then the recipe was further developed into an alginate mussel shell composite. It was time for the next step: How can more of these kinds of materials be developed? Are there any ‘universal truths’ to be found in developing these materials and how can makers/designers be guided in this process? To tackle this problem a multileveled analysis was performed. A literature review of 3D printing with bio-based materials showed that in different fields of expertise, ranging from the medical field to the field of food, the first steps had been made into printing with bio-based materials. Printing experiments were then performed with a selection of binder materials mentioned in these papers. With iota-Carrageenan and kappa-Carrageenan in combination with different kinds of fillers such as rice starch and ground cacao shell, succesfull prints were made. Furthermore, interesting hand-printing results were obtained with chitosan and alginate. More importantly, however, an indicative range of material ratios was found that could help future material developers save time in their search. Finally, some basic guidelines for the printer set-up regarding nozzle size, print head speed and extrusion speed were formulated based on the findings in the experiments. These results led, together with the insights gained from analyzing makerspaces, cookbooks and the Materiom website, to a design proposal for an online material development tool. Currently the Materiom website provides ready-made recipes. As noticed during the analysis phase, however, not every experiment leads to a complete recipe. Also, based on the experience of a material developer, complete recipes are not always what is needed. Recipes can be inflexible and hinder experimentation and innovation. The material development tool provides therefore room for data on different levels. This means that the community can share a larger amount of data and it leaves room for more experimentation and innovation. This idea is brought in practice by dividing data into three different parts: Material information, material compatibility information and complete recipes. Together with a formulaic recipe that gives a starting point for experimentation and printer set-up guidelines, material developers have a range of tools that they can use according to their needs and likings for new material development. And when the experiments have been carried out, the data can be shared with community even when the results were not satisfying and thus saving time of their successors.

Previous research proved the potential of using mussel shell waste as additive manufacturing (AM) material. In this thesis, mussel shell powder was combined with sodium alginate, since it allows reversible cross-linking. Due to reversible cross-linking, this water-soluble and recyclable material can temporarily be made water-resistant, so it can be used for applications that need to be water-resistant. In this thesis, this material was researched, improved, and eventually used to print a prototype of a parametrically designed plant-specific planter.

The circular economy requires high-value material recovery to enable multiple product lifecycles. This implies the need for additive manufacturing to focus on the development and use of low-impact materials that, after product use, can be reconstituted to their original properties in terms of printability and functionality. We therefore investigated reprintable materials, made from bio-based resources. In order to equally consider material properties and recovery during development, we took a design approach to material development. In this way, the full material and product life cycle was studied, including multiple recovery steps. We applied this method to the development of a reprintable bio-based composite material for extrusion paste printing. This material is derived from natural and abundant resources, i.e., ground mussel shells and alginate. the alginate in the printing paste is ionically cross-linked after printing to create a water-resistant material. This reaction can be reversed to retain a printable paste. We studied paste composition, printability and material properties and 3D printed a design prototype. Alginate as a binder shows good printing and reprinting behaviour, as well as promising material properties. It thus demonstrates the concept of reprintable materials.

@en

This PhD project explored how the use of 3D printing can support design in a circular economy. 3D printing is an emerging technology and is viewed as a promising production process for the circular economy because of its unique additive and digital character. The aim of design in a circular economy is to preserve the value of products and materials through lifetime prolongation or high value reuse and recovery. Product integrity and material integrity are relevant for this, because they represent the quality of products and materials to remain whole and complete over time. In this research, we studied how 3D printing can support product integrity and material integrity in a circular economy. Research through design (RtD) was the main research method. In this method the design process is used to generate knowledge and we used a prototyping process to develop 3D printing in the new context of a circular economy. The main contributions of this research can be summarised as following: •We helped establish of a new research direction by exploring design approaches for product integrity and material integrity in a circular economy. •We developed a circular 3D print process flow for product integrity. This is demonstrated by showing that the digital and additive character of 3D printing can be harnessed to develop reversible connections that enable products to be disassembled and reassembled without loss of quality. We developed reversible joints and demonstrated these with a proof-of-concept of a lamp and vase. •We established a design approach for developing reprintable materials. This was demonstrated by producing reprintable materials from locally available bio-based resources, i.e. ground mussel shells with two different binders (sugar and alginate). We designed a lampshade and hairpin and 3D printed them using these materials. •We contributed to the domain of ‘research through design’ by using the prototyping process for knowledge generation; a less common use. The design goal in the prototyping process was used to obtain relevant information (from other disciplines) for developing technology in a new context. This resulted in an iterative process between experimental prototyping processes and scientific knowledge generation. We would like to conclude by nothing that, in spite of all the optimism about the way the use of 3D printing can accelerate the transition to a circular economy, there are currently few 3D print applications that actually support and enable the circular economy. Our exploration shows that to successfully print for product integrity and material integrity, both in-depth knowledge and understanding of the AM production technique is required. @en

Additive manufacturing, also known as 3D printing, is acknowledged for its potential to support sustainable design. In this paper, we explore whether the opportunities that additive manufacturing offers for sustainable design are also useful when designing for a circular economy, and to what extent additive manufacturing can support design for a circular economy. We performed a literature review on the sustainability aspects of additive manufacturing and held a series of interviews with designers about their 3D printed design projects to obtain in-depth information. The interviews were analysed using annotated portfolios, a novel analysis method created specifically for this research. This resulted in a visual representation of the outcomes. We found that additive manufacturing supports circular design strategies by creating opportunities to extend a product's lifespan, for instance by enabling repair or upgrades, even if these products were not originally designed for ease of repair or upgrading. However, the use of monolithic structurally complex parts that support design for recyclability may hinder high value product recovery, like repair. Besides this, the current offer of 3D printable materials should be extended with materials developed for durable use, as well as high-value reuse. Concluding, when accounting for these drawbacks, additive manufacturing is able to support multiple product life cycles and can provide valuable contributions to a circular economy.

@en

This master thesis is the result of a graduation project for the Master Integrated Product Design at the TU Delft. The project was formulated as a continuation on research done by Mariet Sauerwein and Zjenja Doubrovski, in which they proved the potential of mussel shells as a material for material extrusion 3D printing. This with the aim of creation of a locally available material from a current waste stream, exploiting the possibilities of local manufacturing with 3D printing, as this has the potential to contribute to a circular economy.
This project was meant to continue the search for a material made from mussel shells that was printable and recyclable, and find possible applications.
Based on the literature and initial tests was concluded that an additional ingredient was required besides ground mussel shells and water, to create the right viscosity. Research was done into suitable binder materials. Four potential materials were chosen with a weighted criteria method. These materials were sugar, potato starch, iota-carrageenan and NEO-alginate. These four were tested on their effect on the printability and recyclability of the material. Both sugar and NEO-alginate were chosen to continue with as they both had proven to be the best suitable binding agents according to a set of defined criteria.
Relevant technical characteristics of both material combinations were defined by material tests. As the material is developed in this project, there is a certain amount of control over its characteristics by varying certain parameters in the process; Because of this not only the characteristics themselves but also the effect of process parameters was defined. The experiential characteristics, i.e. how the material is perceived, were defined by user tests.
Based on found characteristics a Material Experience Vision was defined. This Vision was meant to give direction and provide guidance through to the ideation process. The Vision is defined as
“I want to create an application in which the material has clear benefits over other suitable materials and fits within a system compliant with the principles of a circular economy. This application will comprise physical interaction with the user, to evoke found positive surprise due to the materials characteristics that differ from materials the user initially associated developed material with.”
With this Vision as guidance three product applications were found through the ideation process. From these three the concept Circular Lighting was elaborated on; in this concept the material was used to create lamp shades in a ‘light as a service’ system. This system was meant for circular built tourist residences. The manufacturer keeps ownership of the light system. Repair and replacement is outsourced to local parties, who would collect the material of the lamps and use it to print new lamps, creating local material loops. A prototype is made of a possible lamp design to validate and showcase the possibilities with developed material.¬

The potential of additive manufacturing (AM) for distributed production is often mentioned as an enabler for sustainable manufacturing within a circular economy. Currently, even if manufacturing with AM is distributed, the used materials can rarely be acquired locally and are usually obtained from a centralized location. Addressing this issue, we are developing an approach that supports the search for local materials that are suitable as material input for AM and are recyclable to serve multiple product lifecycles. The approach is an iterative process consisting of four phases; “material in AM context”, “recycling opportunities”, “material property testing”, and “application possibilities”. As an initial example, we present a process to adapt mussel shell waste into AM material. Mussel shells are a voluminous waste stream in the Netherlands. The shells, which mainly exist of calcium carbonate, are ground into a powder and combined with sugar water. Using a modified material extrusion process, 3D objects are created. In this paper, we discuss the iterations through our approach and illustrate the initial 3D printed results. With this project, we intend to demonstrate the potential of using local waste streams for AM processes for a circular economy. This is a first step towards the development of a methodology for linking local material streams to novel AM processes and meaningful applications.@en

The use of materials derived from waste is one of the prominent ways to contribute to sustainable product design. However, there is a stark gap in literature concerning how people appraise such materials. In this paper, we present our initial attempts to understand the aesthetic appreciation of materials, in particular those derived from discarded raw materials, i.e., revived materials. Two studies were conducted for which we took the aesthetic principle unity-in-variety as the departure point. In the first study, we explored material appraisals by testing whether different visual and tactile qualities interrelate with each other in a similar or contradictory way. Based on these findings, two revived materials were modified and our main assumptions were further explored in Study 2. We outline our findings and show that the aesthetic appreciation of a material can be influenced by the (in)congruity between visual and tactile qualities of the material.

@en

Circular product design is a relatively new approach to design suitable strategies to realize circular products. Additive manufacturing (AM) is seen as a promising enabling production process. It has digital and additive characteristics, which makes AM different from conventional production techniques. However, it is yet unclear how this technique can contribute to circular product design in practice. In this paper, a literature review is placed in context, i.e. the results of a literature review on sustainability opportunities in AM are compared to five typical design cases in a design review. The outcomes of the literature study reveal the aspects of the digital and additive characteristics of AM, that lead to potential sustainability opportunities. We compared these aspects to the circular design strategies as described by Bakker et al. (2014) and Bocken et al. (2016) in the context of the five selected design projects. Each project is described in terms of circular design strategies and how these were achieved through additive manufacturing. Using design practice to reflect on the outcomes of the literature review resulted in a better understanding of the potential of additive manufacturing for circular product design. The relation between the sustainability aspects of AM and the circular design strategies were made explicit. AM seems to be especially suitable to customize parts to fit existing products and to contribute to new opportunities regarding material recycling. These findings deserve further exploration in order to understand the motives for implementation in circular product design.@en

The assignment for this project is to design a presentation for Océ wide format printing to connect the Customer Experience Center(CEC) and to achieve a marketing effect.

Repair was once a common act. With increased product diversity and complexity, a scarcity and obsolescence of spare parts is making repair increasingly difficult and economically unviable. The result is an accelerated turnover of manufactured goods, which are more often replaced than repaired. As products are discarded, embedded materials and energy are wasted.
Alternatively, in a proposed Circular Economy, repair is one of the most efficient strategies of product recovery, retaining as much of the manufactured product as possible whilst restoring its functionality. This makes repair a very effective strategy for sustainability, reducing energy and material waste through product life extension.
An opportunity to revive the habit of repair was found in using 3D printing to produce spare parts for the repair job. This project was initiated to explore the application of 3D printing in this manner, to gain insights and exploring the possibilities with currently available means.
The rise of digital manufacturing and 3D printing accessible to consumers has spawned the ‘Maker Movement’; people making their own physical objects, in a DIY ethic. By enabling ‘Makers’ to create their own spare parts, using 3D printing, a first step in the revival of repair is set.
All three aspects of human, technology and business are incorporated in this project, together leading to a viable strategy for sustainability through design. By incorporating Makers in the role of the repairer and introducing 3D modelling and printing technologies, Repair using 3D printing is found to be a viable concept.
Through an iterative process of practical case study experiments, a complete process of reproducing a viable substitute from an original part is developed. Various repair attempts on actual case subjects are done to explore several methods and options, gaining insights in the parameters and boundary conditions of repair using 3D printing. Resulting from this, a series of written guides and supportive tools are designed and published on popular online Maker platforms. The entire process is covered in the project poster, which includes QR-code links to the tools and guides.
The reproduction process covers three main obstacles: setting requirements for the new part, creating a 3D model and 3D printing it. The major challenge in this project was to enable inexperienced users to do so, using only common materials and equipment. The resulting process involves the decomposition of the original part to set requirements, after which it is measured and CAD modelled, or 3D scanned. For the latter, a 3D printable rotating platform is designed, that supports a photogrammetry-based 3D scanning procedure. Furthermore, two questionnaire-like tools are developed to advise users in the critical decisions of which 3D modelling strategy to apply in the particular case, and what material to 3D print it in.
The repair using 3D printing principle is successfully applied to several case studies, resulting in insights and guidelines for future application. A first step in a widespread adoption of this concept is set by providing Makers with a set of guides and tools to reproduce spare parts on their own. The project concludes with the publication of the developed guides and tools. The thesis overviews the process and outcomes and concludes with recommendations for further development.