The process of 3D printing metal parts is vastly different from traditional ways of metalworking. For one, instead of cutting, molding, and hammering metal slabs, a 3D printer seemingly creates the desired shape out of thin air.
As a result, 3D printing can overhaul a thousand-year-old tried-and-tested tradition. The new method may require a new, ground-up approach to metalworking.
The metal 3D printing process is an additive manufacturing process. It involves creating a shape out of specialized powder. Once the custom shape is printed out, it goes through a debinding and sintering process. The debinding process washes off the binding material from the freshly printed part. After that, it goes through sintering where the metal is heated to make it more compact.
3D printing produces less waste and allows for more complex designs, which will be discussed later in this article. With that in mind, here’s how 3D printing can transform the metals industry.
Role of 3D printing in the current market
Where 3D printing has the best use case in the current industry is in research and development. Due to its short value chain (which we’ll discuss later), metal 3D printing is effective for creating designs and prototypes.
Product managers and designers can create a 3D render and instantly summon a live prototype with the help of 3D printing. This can immensely speed up product development, allowing companies to mass-produce better metal goods. However, at the moment, 3D metal printing isn’t known to perform in long production runs.
That’s because, despite the promising innovation of 3D printing, the process still has some flaws. One of the drawbacks is, 3D printing can’t beat the rigidity of traditionally crafted metal parts. This is because it creates a structure from metal powder, resulting in a more porous final result. A printed metal part will be more prone to cracks and stress than a traditionally milled one.
Additionally, 3D metal printers are costly. Further, 3D printing is still significantly slower than utilizing custom molds. So, as mentioned earlier, 3D printing isn’t very ideal for long production runs.
However, once 3D printing technologies overcome these challenges, they may rebuild the way we produce metal goods.
Methods of 3D Metal Printing
There are various methods in this unique additive manufacturing process. Shown below is the selective laser sintering process.
With this method, a model is formed by directly heating metal powder with a laser beam. This continues for every layer until the three-dimensional model is fabricated.
This is also known as the powder bed fusion technique. That’s because it utilizes a bed of powder to make the model.
There’s also the direct energy deposition method, as shown below.
Here, the powder is printed layer by layer to create a metal model. Think of it as an ice cream machine where the raw material comes out of a nozzle. The guided nozzle dispenses the material, forming a three-dimensional model.
Key benefits of 3D printing
Whichever method a 3D printer uses, the 3D printing process is guaranteed these three key benefits:
1. Wastage is low
Unlike traditional methods, 3D systems produce no waste at all. If there are any, they are very insignificant.
Traditional methods cut through chunks of metal, producing a lot of waste, as shown above. There’s also the grinding and sanding process that polishes rough edges but removes material, as a result. This subtractive manufacturing is not very cost-efficient. Only a portion of the metal you outsource will be used in the final output. You’re lucky if you can recycle that scrap metal for revenue.
However, a process like selective laser sintering only uses the metal powder that’s needed to be used. The powder that isn’t used can be heated for another 3D model.
As a result, 3D printing increases your yield and maximizes your raw material spending.
2. Produces complex designs with precision
The thousand-year-old tradition of metalworking we’ve been accustomed to has limitations. The milling process is hindered by what the machines can achieve, resulting in a relatively inflexible metal design process.
However, since 3D metal printing produces three-dimensional objects layer by layer, the process can create complex designs that aren’t possible with milling as shown in the video above. This allows for hollow materials to be made with much precision—something that cutting and milling have difficulty with.
3D systems may also be able to create lighter-weight parts due to the 3D printing process’ ability to make hollow designs.
With this, there’s a lot of value that 3D systems can bring to the automotive, industrial, aeronautic, and dental industries. However, this can happen only if 3D printing materials can create output as rigid as traditionally processed ones.
In addition, 3D printing techniques allow manufacturers to fuse the production and assembly processes into one. This allows for a snappier design experimentation process.
3. Value chain is shorter
A shorter value chain means fewer markups and shorter turnaround times. 3D printing helps achieve that shorter chain because 3D printing metals only involves atomizing metal (powderizing it), printing the shape, and then debinding and sintering the shape.
On the other hand, traditional subtractive manufacturing involves cutting parts and assembling them. However, depending on the complexity of the overall part’s shape, this process may take longer for each individual piece. There’s also the finishing process to ensure each output has that smooth, polished finish.
Another traditional method is by pouring molten metal onto a mold. The molten metal is then cooled, solidifying it. However, creating molds is another phase of the value chain and is very expensive, especially those you’ll use for long production runs.
Due to this, 3D printing excels in prototyping, R&D, and short production runs.
3D printing maximizes your raw materials, can create hollow and complex designs with ease and has a shorter value chain. Indeed, 3D printing has the potential to transform the metals industry.
But despite the benefits that 3D metal printing promises, there are still some major drawbacks to this process. First, 3D printers are expensive. If one factor in sintering equipment, then the initial cost of 3D metal printing is not too affordable.
Creating molds also costs a wallop, but unlike these long-run machines, 3D printers can only print one part at a time. Paired with the high initial cost, 3D printing is best utilized for prototyping, short production runs, and R&D.
With traditional manufacturing methods, manufacturing costs go down as production scales. Plus, traditional milling processes metal products much quicker than individually printing each part. There’s also the questionable strength of 3D printed parts to consider.
So don’t say goodbye to the good old ways of metalsmithing just yet. 3D metal printing still needs some time to develop before it can disrupt the metals industry. But once those challenges are overcome, 3D printing will forever change the way the metals industry and all other industries that rely on metal goods operate.