How Additive Manufacturing Drives Sustainable Manufacturing

Climate change and pollution are growing concerns in today’s world. Plastics pollution and greenhouse gas emissions are considered to have some of the most significant impacts on our environment. The result is an increase in concerned consumers who demand sustainability in all aspects of the products they use and consume.

The good news is that engineering innovation continues to develop new technologies to combat these problems. Manufacturing is a critical component of the world economy and the lifecycle of every product we use. How can Industry 4.0 manufacturing help address sustainability issues while also delivering value for our economy?

That’s the question facing the 3D Print team at HP.  This company has a long history of fostering sustainability across their product portfolio and sees it as a key part of their reinvention journey, with a vision “to create technology that makes life better for everyone, everywhere.”

Keeping Materials in Use as Long as Possible, at the Highest State of Value

Building sustainability into manufacturing systems and product lifecycle starts here. What is a circular economy? The concept is defined in contrast to the extractive, take-make-waste model behind unsustainable economic practices. Rather than consuming and expending resources, in a circular economy, economic activity builds up the overall health of the system, rather than sapping it.

For example, in an unsustainable linear system, bauxite is mined, smelted into aluminum, formed into cans, filled, consumed and tossed in the landfill. In a circular economy, scrap aluminum cans are recycled into new cans, filled, consumed, and tossed back on the scrap aluminum heap to go around again. Energy is still consumed in the process, but resources are used much more efficiently. Recycling—at the outermost loop—is the most well-known form of a circular economy, but there are others. For example, reusing products, refurbishing, and maintaining products instead of disposing of them also preserves the value of resources longer.

3D printing and digital manufacturing are industry 4.0 processes which can be used to build these circular economies and improve sustainability of economies and value chains around the globe. These two concepts have distinct and different benefits for sustainability.

3D Printing Advances Plastics Sustainability

This is an important question not just from an environmental perspective, but from a cost perspective as well. For example, injection molding creates unavoidable plastic waste in the form of gates and flash which must be removed from the finished parts and recycled.

HP Jet Fusion 3D printers enable industry-leading surplus material reusability of up to 80%. By providing highly reusable printing materials, the company enables production of finished parts that have a lower impact. 3D printing also enables more materials-efficient designs compared to traditional manufacturing, further reducing overall impact.

In mass production, additive is currently positioned as an alternative to injection molding, which is much more commonly used. Injection molding requires a large energy and resource investment up front, due to the mold-making process. Once manufacturers begin shooting plastic into that mold, the energy investment begins to amortize.

According to an independent lifecycle assessment on the environmental impact of injection molding and Multi Jet Fusion printing, HP found that below 5,000 parts produced, additive manufacturing has a smaller environmental footprint than injection molding. In high volume production, all things being equal, injection molding is more efficient. Similarly, the capital cost of AM outperforms IM at volumes low enough that the cost of mold-making is not amortized across the total volume of IM parts.

However, there are other ways that AM can improve sustainability besides the elimination of tooling. HP’s fused bed process contributes to the circular economy within other loops as well.

Use Case Example: Additive Design Freedom Enables Carbon Footprint Reduction

HP has an example of how freedom from traditional design constraints enables additive to reduce the carbon footprint of an aluminum part.

The part targeted for redesign was a subtractively manufactured, machined aluminum part. Aluminum is a fairly high Global Warming Potential material: refining and recycling aluminum requires a significant investment of energy and water.

First, the material was changed to PA12 (nylon), reducing weight by 75 percent. In order to give the design the strength it needed, the part was redesigned using finite element analysis (FEA), reducing material use. The resulting design could only be manufactured additively.

Generative design allows for a reduction in material. The technique is similar to the efficiency of nature: structure is defined by function, resulting in a lighter part with the same strength and functionality. By lightweighting the part, engineers were able to reduce the weight of the part by 93 percent and reduce the carbon footprint by 95 percent. In addition, in some applications such as automotive, lightweighting can have a significant impact on efficiency: for every 100kg removed from a vehicle, fuel use decreases by up to 2 percent. Lattice infill structures are another feature that can increase the strength-to-weight ratio of printed parts.

How Digital Manufacturing Creates Opportunities for a Sustainable Value Chain

Additive manufacturing can compete with and even surpass injection molding when it comes to the lifecycle of parts themselves. But how can digital manufacturing impact the global supply chain?

On-demand printing means you’re only manufacturing what you require, so that there’s less overhead and no need to maintain massive warehouses full of inventory. Instead of shipping raw materials and printed parts across the world at considerable cost to the environment, you’re only shipping digital files to the nearest print bureau. Improving the functionality of products makes them more effective and cost less in the long run.

The world’s container ships produce up to 3 percent of the world’s carbon dioxide emissions. Because additive manufacturing can help massively distribute manufacturing of products and spare parts across the globe, it has significant disruptive potential by reducing reliance on containerships.

As industry continues to place more attention on the importance of sustainable practices, additive manufacturing is poised to deliver more efficient ways to make parts and do business. HP and other OEMs are focusing on building machines that can compete with traditional subtractive processes on cost, quality and flexibility. The aim is to build up the overall health of our system, from an ecological as well as an economic perspective. 3D printing as a process helps to reduce waste in tangible ways, such as reducing the amount of plastic and energy required to produce parts. Digital manufacturing helps to sustain circular economy loops by shortening global supply chains and making parts locally, and by providing a resource for replacement parts so that products can be repaired, not discarded.

Interestingly, the growth of another sustainable technology is helping to drive adoption of additive in the automotive industry: electric vehicles. Because automakers are developing new platforms for EVs, there are more opportunities for new design thinking in the components of these vehicles, as opposed to replacing existing part designs on established car models.

As additive manufacturing continues to grow, adopters and consumers will continue to find new, innovative and sustainable ways to move from linear, wasteful economies to circular, healthy ones which preserve our resources, dollars and our planet.

To learn more about the sustainability benefits of additive manufacturing, visit the HP website.


HP has sponsored this post.  All opinions are mine. –Isaac Maw.