Additive manufacturing (AM), often referred to as 3D printing, is revolutionising how products are designed and manufactured across various industries, including aerospace, automotive, and healthcare.
One of the most significant advantages of this technology is its ability to create lightweight materials. Understanding how advancing additive manufacturing contributes to weight reduction involves exploring its design capabilities, material efficiency, and innovative processes.
Additive manufacturing is an inherently material-efficient process. Unlike traditional subtractive methods that cut away material from a solid block, it builds components layer by layer, which minimising waste.
This efficiency contributes to lightweight design by only using the material necessary for the structure, creating lightweight parts that meet performance requirements without excess weight.
It can also employ advanced materials, such as high-strength polymers and metal alloys, that are designed specifically for lightweight applications. These materials often possess superior properties compared to conventional materials.
Additive manufacturing enables the integration of multiple parts into a single component, reducing the need for fasteners and joints. This consolidation leads to fewer interfaces, reducing weight and potential failure points in a design. Fewer connections can lead to a more robust and lightweight structure. Additive manufacturing can produce intricate assemblies that would traditionally require multiple components to be fabricated separately. This complexity can lead to lighter overall designs.
With additive manufacturing, parts can be easily customised for specific applications or loads. This adaptability allows engineers to design parts with varying densities or material compositions tailored to specific performance requirements, enabling the creation of lightweight structures that maintain necessary strength.
The ability to quickly produce and test prototypes allows for iterative design processes that lead to more efficient and lightweight final products.
One organisation at the forefront of this sector is the University of Exeter’s Centre for Additive Layer Manufacturing (CALM) – a leading independent research centre, focused on supporting the development of advanced High Performance Polymers, driving innovation, and creating new knowledge around materials and processes for Additive Manufacturing.
Since its initial interactions with Hosokawa Micron – based at Sci-Tech Daresbury in the Liverpool City Region – in the mid-2010s, a partnership has evolved into a groundbreaking initiative aimed at developing advanced materials for additive manufacturing.
The relationship began when CALM required subcontract mechanical grinding services to convert high-performance polymers into powder suitable for 3D printing using powder fusion processes.
By 2017, the University of Exeter was investigating new multifunctional materials and began assembling a consortium that included key industry players such as Victrex, a leader in PEEK (polyetheretherketone) materials.
With both Exeter and Victrex having prior experience working with Hosokawa Micron, the latter became an obvious choice for this ambitious project. The collaboration aimed to develop new nano-composite materials that enhance properties like lightweighting, electrical conductivity, and thermal performance.
The proposal, submitted to Innovate UK in late 2017, was set into motion in June 2018, involving an impressive consortium of partners, including Qioptic Limited (now Excelitas Technologies), Versarien Technologies Limited, Haydale Limited, Thales, and Airbus.
At the core of the project was the integration of graphene with PEEK, a high-performance material known for its exceptional mechanical and chemical resistance, particularly in high-temperature environments. Incorporating graphene into PEEK is a promising route into new advanced applications due to the combination of properties offered by the two materials. The nanocomposite could be used as lightweight heating devices, de-icing materials in aerospace and civil engineering, conductive plastics for satellite parts, and submarine pipelines . Graphene has also been found to be useful in improving tribological properties such as wear properties in PEEK material and can promote bone osseointegration and bone regeneration
A key challenge in this project was effectively dispersing the nano-materials within PEEK and grinding them into a powder form for the powder bed fusion process. Traditional methods involved melting the polymer, which posed difficulties due to PEEK’s strength, leading to damage of grinding equipment.
To overcome this, the team turned to Hosokawa’s mechanofusion system. This innovative technology facilitates dry particle-to-particle fusion through mechano-chemical reactions, allowing for the creation of a new nano-composite material tailored for 3D printing.
This compact and entirely unique piece of equipment has been specially designed for facilitating dry particle-to-particle fusion, to enhance particle performance, control particle shapes by making them spherical or flat, precisely distributing and finely blending particles and to create an infinite number of new functional materials by generating a mechano-chemical reaction between two or more organic or inorganic substances, metals, ceramics or other materials.
With the right PEEK grades and functionalisation from using the Haydale HDPlas plasma process (Haydale, UK)., the mechanofusion process enabled the development of materials with optimised shape, size, and composition for additive manufacturing. To create plasma-functionalised nanomaterials, a process gas was introduced into a rotating vacuum chamber. An electrical potential was applied, and the gas was dissociated into its component parts. The dissociated ions from the process gas bombard the nanomaterial, producing chemical groups covalently bonded to the nanomaterial surface.
The resulting multifunctional materials offered significant benefits, particularly in the aerospace sector. Their lightweight yet strong characteristics make them suitable for various applications, from cabin components to de-icing materials. Additionally, the improved conductivity opens avenues for use in satellite components and defense applications.
Powder bed fusion technology, characterised by its precision in layer building—approximately 0.1 mm thick—allows for intricate designs and accurate dimensional control. This technology, combined with the new materials, provides unique solutions for high-performance components, eliminating the need for support structures and enabling complex internal designs.
Projects of this complexity necessitate a deep understanding of material and process interactions to optimise all aspects of the system. The academic rigor provided by the University of Exeter ensures thorough research, while industry partners like Hosokawa Micron offer practical insights and guidance on commercial applications and scaling.
This collaboration exemplifies the innovation at the heart of the UK’s manufacturing and engineering sectors. By bridging the gap between academia and industry, such partnerships challenge conventional practices, facilitate knowledge sharing, and lead to exciting new ideas.
The collaboration between the University of Exeter and Hosokawa Micron is a testament to the power of interdisciplinary partnerships in driving forward additive manufacturing technologies. As they continue to explore and develop advanced materials, their work holds the promise of transforming industries and paving the way for future innovations.
As additive manufacturing technology continues to advance, the potential for creating even lighter materials will grow. Innovations in printing speed, material formulations, and design software will enhance the capabilities of additive manufacturing, making it a cornerstone of lightweight design across multiple sectors.
In conclusion, advancing additive manufacturing creates lightweight materials through optimised design freedom, material efficiency, integration of components, and the use of innovative techniques and materials. This transformative technology is reshaping the manufacturing landscape and contributing to more sustainable and efficient products at a time when they are needed more than ever.
Authors: Kathyn Hipkins, Technical Operations Director, Hosokawa Micron Ltd
Paul McCutchion, Manager, Exeter Technologies Group at University of Exeter
Dr Yaan Liu, Postdoctoral Research Fellow, University of Exeter
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