Is Additive Manufacturing and Sustainability a match made in Heaven?

Hidden emissions and rare materials make this answer a complicated one.

Optimising a single step in the production process creates advantages that reverberate throughout the supply chain. For instance, simply using lighter build materials reduces manufacturing energy usage, cuts transportation fuel consumption, allows more units to be delivered simultaneously, and cuts distribution costs. Now imagine the environmental, creative, and financial benefits of overhauling multiple steps along the production process.

Traditional manufacturing is often constrained by a global supply chain with multiple blind spots. Anything from a delay in an offshore factory to a hurricane in the Atlantic can hinder production and distribution. Hence industries such as automotive, aerospace, transport, and AEC are adopting Additive Manufacturing (AM) with its localised production and sustainable supply chains. A word equally celebrated and bastardised, ‘sustainability’ is thrown around in business discourse, often without real commitment. Does AM’s sustainability credentials hold up to scrutiny? The short answer is: yes. The long answer is: it’s complicated. Continue reading for the latter.

“Sustainability analysis is often done at the end of the design process when a product’s impact has been locked in”

Whether a completed product or a single component, the design phase not only determines a project’s success but also up to four-fifths of its lifetime emissions. Any project is a race against budget, time, and resources. Hence, the choice of unsustainable build materials can bring a product down with the heavy delays of recalls, redesign, and increased lead times. It’s then imperative that a product’s digital twin is perfect before it exits design and into production.

Designers have been making great strides in this department with Autodesk Fusion 360’s Makersite add-on which basically gives them the power of foresight. Translating a product’s CAD model into a Bill of Materials, the add-on calculates the cost and carbon emissions associated with each part. It also recommends designers a list of sustainable materials that can be easily swapped in the CAD model.

“We’re giving designers the tools to make better decisions, more quickly,” says Zoé Bezpalko, Autodesk’s Senior Design and Sustainability Manager. “Sustainability analysis is often done at the end of the design process when a product’s impact has been locked in. To reduce environmental impact on a large scale, we need many more accessible sustainability tools of this kind.” With insight into parameters such as carbon footprint which can’t be reliably calculated until after production, the Makersite add-on creates a holistic workflow where designers can bring down costs, decrease prototypes and design iterations, avoid supply chain risks, and adhere to product compliance.

Metals are tricky to work with; they’re expensive, often need to be imported from abroad, and a lot of leftover scrap is wasted. So the ability to 3D print metals down to the exact amount is an AM dream come true. Markforged is leading the charge with their Metal X 3D printer which is allowing EV manufacturers to fabricate complex parts such as busbars. These electroconductive metal bars distribute electricity to different parts of an EV. Copper is the material of choice, but its perfect electroconductivity is balanced by it being difficult to work with, hence higher costs and longer lead times. Costing $200 per iteration and a lead time of three weeks with traditional manufacturing, the Metal X cures this headache by printing busbars for only $55 with a lead time of three days.

“The Metal X,” says Ross Adams, Markforged’s Global Metal Product Manager, “can turn around nine iterations in the same time it takes to get just a single iteration through traditional fabrication.” This strengthens the supply chain by speeding up and localising production while freeing up engineers to test the parts in real-world conditions.

Bruce Bradshaw, Chief Marketing Officer of materials producer 6K Additive, is sceptical of the sustainability behind most metal 3D printing. “The metal powders used in AM processes have to be treated first with gas or plasma atomisation – coming with a sizeable environmental price tag. With low yields and high waste, both processes expend prodigious quantities of energy.” Furthermore, many products require expensive, carbon-intensive, and rare materials to achieve sustainability during use. For example, Lithium for EV batteries.

This is when informed design and production decisions are required to offset the emissions released before the beginning of manufacturing.

Although manufacturers are cutting emissions on a product level, there’s unavoidable environmental damage done on a process level. Relativity Space’s 3D-printed rocket launch may have created a sustainably made product but the environmental cost of the rocket fuel and the soot particles released in the atmosphere isn’t worth it.

AM supplements rather than replace traditional manufacturing, so judgements must be made about where to apply its capabilities. Sustainability isn’t a solution to a problem but an opportunity to rethink our methods of production and consumption. AM is enabling that by emboldening designers and engineers with a wider toolkit to actualise their visions while creating more resilient supply chains and promoting localised production. After all, sustainable products ensure sustainable companies.

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