52 advantages of 3D printing with Metals

Bas Koper
03 aug 2018

Customers always ask us why they should look into the possibilities of 3D printing in their business. Almost every tech company is these days busy with innovations in their own industry. Most potential clients we talk with are frightened by the new technology of printing because they don’t see the benefits for their own business but they do see that others are implementing it in a rapid pace. In this blog you will find 52 reasons why you should look into the possibilities of implementing Additive Manufacturing for production of your products and why this technology will give you advantages with respect to the competition in your industry.


  1. Little preparation time is required

Every manufacturing process needs preparation time. When comparing 3D printing to machining or casting it takes a lot less time in preparations. Regardless of the complexity of the product, the preparations for 3D printing take on average between 1 – 1.5 hours. Machining complex components usually requires a preprogrammed machining plan (3-4 hours) + collection of the right tooling (1 – 2 hours) + setup of the machine (1 hour) which adds up to 5-7 hours. For castings the preparation of a mould usually takes even longer and therefore the preparation time (and costs) of 3D printing is very low compared to other techniques.


  1. Low set-up costs

Due to preparation time, setup of machines require time and materials. This means that every machine has certain set-up costs. For machining the costs are mainly coming from hours spent in programming and required tooling. For castings the costs are mainly in creation of a mould. 3D printing, or Additive Manufacturing requires very low set-up costs. On average the set-up costs are 1 hour of programming and 1.5 hours of machine setup. Therefore the total set-up costs for a new build usually do not exceed EUR 250, while this can be easily EUR 750 for machining and EUR 3500 for casting.


  1. Quick time to market

The possibility to significantly reduce preparation time and setup costs leads us to the fact that the prototyping phase of a new 3D printed product can be significantly quicker than other manufacturing techniques. This advantage allows for superfast development and very short time to market required. Instead of 10-15 weeks of delivery time for castings the products can now be printed within 3 weeks maximum.


  1. Suitable for small series production

Small production series can be easily produced on a build plate or a sequence of build plates. If the products are well nested on a build plate one can produce batches up to 200 items (dependent on the dimensions of the parts and the build envelope of the 3D printer). The big selling point for Additive Manufacturing using Selective Laser Melting or Direct Metal Laser Sintering is that the products produced have equal or better material properties compared to castings. Therefore one can decide to print a small batch of products that were designed for casting to save the costs of mould preparations.


  1. Allows for quickly trying out and iterations of prototypes

The prototyping phase can be a long iterative process in which lots of resources are spend. This means that the prototyping phase is in general a highly cost ineffective period in the product development phase. Iterations are not only expensive but also time consuming: machining and casting can take up to 10 weeks for each iteration. With 3D printing companies are able to have a new product iteration within 3 weeks and in a cost effective manner: no costs for an update of a mould or machining software.


  1. Practical for production of spare parts

If complex spare parts are urgently needed and no suitable parts can be delivered on demand, often the most rapid process is 3D printing. With Additive Manufacturing even the most complex parts can be printed directly without long preparations of a mould or time to prepare a machining program.


  1. Print on demand instead of keeping warehouse stock

Spare parts are capital intensive: it can take years before a client requests a particular component and therefore it can take years before this part of the inventory is generating cashflow. For manufacturers of machines it is therefore a capital intensive part of the inventory on the balance sheet of the company. Additive manufacturing allows for cost-effective availability of spare parts: the parts can be economically printed within 3 weeks and on demand per part which allows for lower stock quantities in your warehouse.


  1. Produce unique replacement parts

Existing machines need spare parts. Whenever parts are replaced by spare parts, the spare parts can be an update of the original parts to further improve the performance of the machine. Additive manufacturing allows for constant optimization of replacement parts without increase increasing costs or increasing delivery time. It is an unique technique that can even adapt to the most radical changes without extra preparation time.


  1. Suitable for producing 3D scanned parts when part files are missing

Legacy parts of machines that are out of production are often hard to obtain. It often happens that the technical drawings of those legacy parts are missing as well. Especially in these situations 3D technologies can provide great benefits: 3D scanning for dimensioning of the product and 3D printing used the scan data for production of the spare part.


  1. Possibility to adjust a part without having to change the production approach

3D printing allows for adjustments in design of parts without having to change the production techniques. For casted products an adjustment in design usually requires redesign of the mould, which is a costly and time consuming process. Similarly, adjustments to the design of machined parts usually results in (partial) rewriting of the machining program which can also be a costly and time consuming process.


  1. Possibility to make custom, one off, products

With traditional manufacturing methods there is always an economical batch size: the amount of products that justifies the preparations for production and post-processing of parts. For Additive Manufacturing the economical batch size is independent of the amount of products, and purely dependent on the size of the build plate. This means that several products can be printed at the same time and therefore the economical batch size for every product starts at 1 item. This makes it economically possible to make custom, one off products.


  1. Additive manufacturing offer unparalleled design freedom

Traditional manufacturing methods have several limitations compared to additive manufacturing: additive manufacturing can combine several complex shapes including but not limited to products with cavities, internal structures, lattice structures and even fluent internal channels for optimized flow of gasses or fluids. These features are impossible or extremely expensive to make with traditional methods such as casting or machining. However, for selective laser melting all these features are possible. This gives design engineers unparalleled freedom in their designs. Products can be created in the most perfect shape, without constraints of manufacturing techniques.


  1. Allows for manufacturing porous structures which have benefits in medical and other applications

Porous structures allow for many design features for a variety of products. Especially in applications where the product should be accessible by other media such as medical devices. However this feature can also be very practical for other industries. For instance with heat exchangers or structures that require varying strengths in multiple directions. The advantage that additive manufacturing brings on the table is that the porosities can be random and also varying over many different sides or the product, allowing for design features that have never been possible with traditional manufacturing methods.


  1. Free form designs can be manufactured just as easily as designs with straight lines

Other than traditional machining it does not take any efforts to vary between free form designs or straight line designs! It’s incredible isn’t it?


  1. Allows for the production of shapes which are impossible to manufacture with other techniques

A titanium hinge from one structure, manufactured as one part? An Inconel heat exchanger with optimized random cooling channels, manufactured in one go? A metal hollow product which is manufactured as one object? All these  items have one thing in common: they can only be manufactured by 3D printing. These objects have features which are either practical for the application and/or cost effective but were never available before.


  1. Possibility to make hollow, thin walled structures to achieve mass savings

Imagine how weight saving can help your machine perform faster, without sacrificing durability and operational life time. Additive Manufacturing allows for great savings of mass which will result in smaller inertia’s of moving components allowing for either higher performance for the client or lower costs for motors, hydraulic systems and electronics for you as a manufacturer.


  1. Possibility to create internal 2D honeycomb or 3D lattice structures for enforcing lightweight parts

Honeycomb or lattice structures can be a great solution if a redesigned part should be lightweight and should maintain its original ‘solid’ shape. Honey comb structures or lattice structures can maintain the rigidity of the part and save an enormous amount of mass at the same time. 3D printing allows for very complex internal structures, with only small efforts, that cannot be created with a different manufacturing technique.


  1. Complex, lightweight parts produced with topology optimisation can be manufactured with Additive Manufacturing

Today we have software tools that help us generate structural designs that have bionic shapes just as nature would develop a structure over time. Those structures are the optimum between structural mechanics and usage of material (mass) in the structure for the specified loading conditions. These bionic shapes are often possible to machine or cast but requires rather complex programming/machining or a complex mould. Additive manufacturing brings various great advantages to the table for these kind of products: It does not take more effort to create complex shapes than rather straight simple products. Secondly the material used is purely used to create the product, without any waste. This is especially interesting for the more expensive materials: machining of such a product would easily create 40-50% of swarf.


  1. Possibility to manufacture parts with incorporated meta materials

Additive manufacturing is a very useful technique to produce products which contain lattice structures. These lattices can have varying moments of inertia which gives the material the possibility to produce different stiffnesses in adjacent directions. This feature is also known as meta material and will bring a whole new dimension to high performance products for instance in medical, aerospace and sports industry.


  1. Meta materials can allow for varying material properties throughout the product

Isn’t it incredible that a product can be very flexible in one direction and very stiff in another direction? Imagine how to create those properties with another technique than additive manufacturing, that is almost impossible to work out!


  1. Meta materials produced with AM can exhibit a negative poisson’s ratio

The poisson’s ratio is the ratio of the decrease in width to the increase in length of a material sample that is being stretched elastically. Intuitively, a positive poisson’s ratio makes sense. When you stretch a piece of material, it shrinks laterally. With additive manufacturing it is possible to build up metal mesh structures that actually expand laterally when stretched! This is a useful trick used in hip implants to ensure that material expands on both sides of the implant when it experiences a bending load.


  1. Lots of freedom to tweak properties such as thermal conductivity or natural frequency of a product

Due to the freedom of design and possibility of using meta material structures, additive manufacturing offers a lot of freedom to adjust thermal conductivity and the natural frequency of a product without changing its outer shape. This can be especially useful in aerospace applications.


  1. The AM process produces little material waste. This is especially beneficial for expensive metals

The average metal 3D printed product requires print supports that are about 15% of the mass of the product. Some require none at all! Besides that, a tiny fraction of the used material powder will be filtered out during powder filtration to ensure good powder quality. With machining methods however, as much as 90% of the used material can be waste material. Especially for expensive metals, this is a big benefit of AM.


  1. Small machine footprint

AM machines have a relatively small footprint whilst offering the capability of producing an endless variety of product.


  1. Energy efficient production

Especially for complex products that would otherwise require many machining operations to produce, Additive Manufacturing is a more energy efficient process. Laser power is applied to the powder bed with great precision.


  1. Cool lasers!

Up to 1KW lasers are used in the additive manufacturing process. Strong enough to shoot aircraft from the sky!, …….. probably, ……..maybe not. But still cool!


  1. Print powder can be recycled

Additively manufactured products are build up in a build chamber that is filled up with material powder layer by layer. Only a fraction of the powder used in the process ends up in the product. The remainder of the powder gets filtered to ensure no sintered particles are left behind in the recycled powder that can be used again to create more printed products.


  1. Lightweight parts made possible by 3D printing results in more energy efficient machines or transport

For any moving part the following applies. The more lightweight the part, the lower the inertia contribution, the less energy is required to move it. Thus, lightweight parts result in more efficient or less energy demanding machines and transportation. With the production freedom delivered by AM, parts can be designed to be more lightweight than ever before.


  1. Complete freedom to create aesthetically pleasing designs!

Again, design freedom. Design whatever odd shape you want without having to worry about whether or not it can be produced. Additive manufacturing opens up new possibilities for designers and artists to come up with complex new shapes.


  1. Mirror finish possible after polishing

Straight out of the printer, a material roughness of about 6 Ra can be expected. After some tumbling and/or media blasting, a roughness of 2-3 Ra is attainable. With proper polishing, a mirror finish (<0.8 Ra) can be achieved on AM produced parts.


  1. Possibility to create internal features such as cooling channels

Additive manufacturing offers the possibility to design internal structures within parts. Such structures cannot be created with other methods without assembling, bonding or welding parts together. Integrated internal cooling channels are probably the most prominent example.


  1. Air or liquid channels can be designed and manufactured freely for optimal flow characteristics

In doing so, more laminar flow characteristics can be achieved. It is also possible to design pipe connections fittings such that the flow is minimally obstructed and thus a smaller pump can be used to for circulating liquids.


  1. Heat radiators or exchangers can be made in complex shapes that optimize performance
    In order for a heat radiator to work efficiently, a large amount of radiating surface must be present whilst also allowing for proper heat conductivity through the radiator. This combination of requirement results in very complex shapes when such a product is optimized. These shapes are however extremely difficult to produce without AM. Additive Manufacturing is now making much more efficient designs feasible.
  2. 9+ % material density
    The quality of metal 3D printed parts is getting better and better every year. Various printed materials are now approaching 100% density. This means that even for products that have to be fatigue resistant, additive manufacturing is now a viable production method. This is why even critical aerospace components are now being developed.
  3. Relatively high material ductility
    Various alloys exist with varying properties. With AM it is possible to create relatively ductile products. This means that the material can achieve significant deformation without large stresses being created in the product. High material ductility is not necessarily an advantage but it can be one in some applications.
  4. Large variety of metal (and polymer) materials available and more and more being added every day
    Dozens of various metals and alloys are already available for 3D printing. Some with equal or similar material properties to their bulk counterparts, others with unique material properties. Improvements to existing options as well as new printable materials are continuously being developed.
  5. Lots more potential in the future. Getting into 3D printing now ensures that you stay on the cutting edge of production
    Learning how to design and incorporate AM produced components into your products might or might not deliver significant benefits today, depending on the type of product. You will however be able to recognise a part that is suitable for AM when you see one. For businesses, it is important to note this technology will only get better and more cost efficient in the future. It is better to adapt now to ensure you don’t miss out on opportunities to improve and stay ahead of the competition.
  6. Form freedom manufacturing can allow for a strong reduction in part count in assemblies
    It is often possible to reduce the part count in an assembly by combining various components into one part. This combined part might not have been possible to manufacture efficiently in the past, but AM is making this possible in many cases. By combining various parts into one component it is possible to streamlining the design process, reduce track and tracing efforts, assembly time and ultimately costs and production times.
  7. Combining parts leads to a more optimized design, increasing product performance
    After combining several parts into one larger part that can be produced by AM, it is possible to optimize the whole structure more efficiently compared to optimizing all the separate parts that previously made up the assembly.
  8. The elimination of bonds, welds or other types of interfaces results in a more structurally sound product
    Interfaces often turn out to be too week or to strong. If they are too weak, they will cause to product to fail sooner.
  9. The elimination of interfaces can reduce the amount of work required to clean a product
    Combining multiple assembled parts into one part eliminated interfaces, which get dirty easily. This can be especially important in the food industry where machine hygiene is very important. If a food processing machine does not get dirty as quickly, less machine maintenance is required.
  10. Design of parts can be simplified by not having to take into account regular machining restrictions and tool access
    Almost anything can be produced with metal 3D printing. Even though there are some simple rules which should be taken into account in order to ensure that the product can be produced in the most efficient and least costly manner, design for AM can be relatively simple compared to, for example, machining.
  11. Adding extra features to a product can be done easily, without adding significant costs
    Last minute design changes are usually no problem and will have little to no effect on the production costs. It also easy to make adjustments to a product that is already in series production since there is no need to change the production process.
  12. The use of topology optimisation can speed up the design process whilst also resulting in mass optimized parts. Easy to print!
    Topology optimisation programs perform iterative stress analyses on a given design with specified applied loads. After each iteration, some material is taken away from the parts of the design where stresses are low. In this manner, the part can be designed to deal with applied loads in the most material efficient manner. Usually, the result is an organic looking structure. Difficult to produce with most production methods, no problem for 3D printing!
  13. Design drawings are not strictly necessary. A 3D file is enough to start 3D printing
    For complex products, creating proper technical drawings can be a time consuming task. This is not necessary for the AM process since the 3D file itself is used to determine the laser pattern that needs to be followed in order to build up the product. If you are unfamiliar with 3D printed products, it is best to specify requirements on surface roughness’s and important tolerances. It might be necessary to perform extra surface treatment or post machining for tight tolerances.
  14. Short lead times
    Work preparations require little time. Time to print can vary from hours to days, depending on the product and process specifics. Some products will require heat treatment, which could take up another day. Print support removal and standard surface
  15. Production under controlled, inert conditions
    Some metal powders slowly degrade if they are in contact with oxygen. Therefore, it is important to keep 3d printing powders in an inert atmosphere. New print powder is delivered in air sealed containers filled up with argon gas. These containers are placed inside the AM machine. Subsequently, the machine is filled with argon gas before the containers are opened and the powder is placed in the powder chamber. This powder chamber can be closed off when the printer has to be opened. Printing is also done under argon atmosphere. Overflow powder and the powder that is removed from the build chamber after the print is finished ends up in the overflow container. This container is sealed off before the machine is opened to take out the products. The filter station is also flushed with argon before the overflow chamber is attached to the filter station. Thus, the powder remains in an argon atmosphere at all times until it ends up in a product. Quality material is the first step to delivering quality products!
  16. Print parts together that would otherwise be impossible to assemble like interlocking parts
    It is possible to print interlocking parts like chains. Since this has not been possible before, it is difficult to come up with applications where this feature might be useful. Surely someone will find a good application for this new possibility!
  17. Good material weldability
    The print process is basically a high precision welding process on the micrometre scale. Therefore it should not come as a surprise that materials which are suitable for additive manufacturing tend to be very suitable for welding. This property can be useful when a part is too large to fit in a AM build volume. Restricted build volume is still one of the main restrictions of additive manufacturing.
  18. Tolerances sufficient for most applications
    High quality additive manufacturing machines can realistically reach an accuracy of +/- 0.1mm on 100mm. This can be slightly improved with thermo-mechanical build analyses and/or iterative scaling adjustments. Micrometre accuracy should however not be expected. For many applications, AM can deliver sufficient accuracy.
  19. Possibility to do post machining to reach strict tolerances
    If micrometre level or better accuracy is required, it is always possible to perform post machining in order to reach the required accuracy.
  20. Possibility to produce an endless variety of products on one machine
    Due to the versatility of additive manufacturing an endless variety of products can be produced on a single machine, even in a single print job! Often, it is even preferable to build various different parts on a single build in order to make the most efficient use of the available build volume.
  21. Printing 2D objects is also possible
    It is also possible to print thin 2D objects! But… for large batches it is unlikely to be the most efficient production method. Many products can be produced with a less costly method. Some however, are best produced with Additive Manufacturing. It is unlikely that 3D printing will ever make all other productions obsolete. But, as the technology is maturing, more and more products are becoming (economically) suitable for additive manufacturing and this trend will surely continue for a long time to come.