Additive manufacturing, more commonly known as 3D printing, is a method whereby an object is constructed through the addition of layers (Figure 1), rather than by subtraction or injection molding. In subtractive manufacturing material is removed, like when a woodworker whittles a figurine from a block of wood; in injection molding, as the name suggests, a molten material is injected into a mold, which is then removed. One great advantage of additive manufacturing is that it gives designers much more freedom to make structures which would normally be prohibitively complex due to factors like lack of tool access (subtractive manufacturing) or undercutting (injection molding). 3D printing is also a very versatile process, while often associated with small cheap plastic objects, 3D printers can be designed to print using almost any media, ranging from metals to food to bone.
The company I am looking at for the megatrend of additive manufacturing is Porsche. Porsche is a German automobile manufacturer focusing on high-end high-performance vehicles. Additive manufacturing will be an important factor for product development in two main ways. The first is the ability of 3D printers to build novel and complex architectures. In particular, hollow parts will allow Porsche to make lighter components, and thereby lighter cars, without having to sacrifice performance. In the automotive industry, weight is an incredibly important consideration, as it affects things like fuel efficiency, acceleration, handling, and braking. The second benefit of additive manufacturing is that a single 3D printer can make a variety of parts, thereby removing tooling costs which are typically the most expensive fixed costs for low volume production. You can see how this bears out in a reduced cost for production of metal part below quite high volumes (Figure 2).
In the short term Porsche is positioned to use 3D manufacturing for obsolete replacement parts. In the auto industry, original factor parts are typically in good supply for 5 years, but cars are kept (in the US) for an average of 11.4 years. This clearly means that older cars, and especially classic cars, are very hard to repair with genuine parts. There is little incentive to produce these parts, because the fixed costs to reproduce a part with volumes at such low levels is prohibitively expensive. With 3D printing on the other hand, Porsche can make even just one or two copies of a part for a classic car at roughly same cost per part as a new mass-produced part, and even using the same machine.
Replacement parts for classic cars is an extremely niche market, and so it would not be worth it for Porsche to move into 3D printing unless they have a longer-term strategy over the next 5-10 years. After establishing 3D printing for replacement parts, Porsche will look to 3D printing for mass production of parts, with an eye towards pushing performance benchmarks through weight reduction. With global sales of roughly a quarter million cars per year across all sub-brands and models, the cost to manufacture all of their larger parts through 3D printing would be financially comparable to (or even cheaper than) traditional methods; this will all be possible while reducing the weight of parts through techniques like hollowing out, without reducing durability.
In the short term I would suggest that rather than 3D printing obsolete parts, that Porsche distributes their .3D files (a format usually used to digitally render the object to be printed) for these parts to individuals or garages. The benefit of this is that they will create a lot of goodwill with loyal car enthusiasts, while giving up what is a very small market.
In the longer term (5-10 years) I see two main additional uses for 3D printing: customization and Just-In-Time manufacturing. 3D printing will provide greater flexibility in the building of parts, and could allow for made to order cars with some level of customization; customization would need to be limited to specific parameters in order to maintain high performance and safety, but for example, trunk length might be customizable depending on customer need. More importantly, being able to produce parts on demand and as needed, will allow for Toyota Production System Just-In-Time part creation.
An open question remains about whether additive manufacturing can make car production a local endeavor. Will 3D printing become simple but robust enough so that dealership lots full of new cars will be replaced by buildings for manufacturing customized cars made to order?