Metal Additive Manufacturing Market Estimated to Grow by 4.42 Billion by 2024

Powder bed fusion

Powder bed fusion technologies, such as direct metal laser sintering (DMLS), selective laser sintering (SLS), and direct metal printing (DMP), build three-dimensional objects by depositing powder layers on top of each other and applying heat source, such as laser or electron beam, to consolidate the adjacent layers. 

Image via 3Dnatives

Video of PBF by Solid Concepts

Powder bed fusion technologies are relatively inexpensive compared to traditional methods and more suitable for prototyping. However, it also has its challenges, such as relatively slow speed of printing, product size limitation, and laborious processing requirements. Nonetheless, it is still the most mature and widely used metal additive manufacturing process. For example, Morris Technologies helped GE Aviation print a fuel nozzle using powder bed fusion technologies. All 20 parts were combined into a single unit and it was 25% lighter and 5 times more durable than its predecessors.

Direct energy deposition

Direct energy deposition (DED), such as laser-based, electron beam, and plasma or electric arc based DED, is similar to powder bed infusion since both of them use a focus energy source; however, DED melts the metals, in the form of either powder or wire, as they are deposited. Aside from that, electron beam-based systems DED must take place in a vacuum so that the electrons will not be affected by air molecules. As for laser-based DED, it has to be performed in chambers with inert gasses to protect the reactive metals.

Image via 3Dnatives

Video of DED by BeAM Machines

DED is capable of creating parts from scratch but is more commonly used for repairing by adding melted materials to existing parts. Compared to other metal additive manufacturing technologies, DED has a faster build rate and can produce larger parts; however, it also has relatively lower build resolution with poorer surface finish. 

Wire arc additive manufacturing

Wire arc additive manufacturing (WAAM) is a variation of DED that uses electric arc as the heat source to melt metal arc and fabricate parts. As the metal wire becomes melted, it is extruded as beads and these beads will stick together to form layers of metal materials. These layers will then form the metal parts. 

Image via WAAM

Video of WAMM by Tecnalia

Unlike PBF, WAAM has the ability to manufacture large-scale metal parts and the welding wire is much less expensive than the metal powder used in metal PBF. Aside from that, worn-out or damaged parts can actually be repaired with WAAM to eliminate the cost of replacement. 

One of the challenges faced by WAAM is built-up of residual stress as a result of extreme change of temperature involved in the process. Residual stress might cause the parts to have different forms of deformation, which affects the integrity of the parts. In addition, parts might have poor surface finish and therefore require post-processing. 

Binder jetting

Bound metal deposition (BMD), or bound powder deposition, is different from other additive manufacturing as the powders used in BMD are bound together with both wax and polymer binder.

Image via ExOne

Video of binder jetting by ExOne

This process allows the materials to become safer and easier to use compared to loose powder. These materials are then heated and extruded onto the build plate to form layers of metals, resulting in a part composed of several layers. The binder is then removed and the layers are then sintered directly after printing for the metal particles to densify. Compared to other major metal additive manufacturing technologies, BMD is said to be more affordable and is capable of printing all part geometries. However, parts printed with BMD often require post-processing, post-machining or polishing.

Stainless steel

Image via Axom

Steels, particularly stainless steels, are one of the most commonly used types of materials for metal additive manufacturing. Several industries, such as automotive, industrial, and medical applications, use stainless steel for metal additive manufacturing as it has several properties, such as hardness, corrosion resistance, and impact resistance. Engineers have used stainless steel to produce parts of jet engines, rockets, and even nuclear facilities

Titanium

Image via 3DPrint.com

Unalloyed titanium has a wide range of applications in metal additive manufacturing. Aside from its balance between formability and strength, other characteristics of titanium, such as strength to weight ratio and resistance to corrosion and heat, make it the ideal material for a variety of parts for jet engines, missiles, airplanes, orthopedic implants, etc.

Aluminium alloy

Image via Sculpteo

Aluminium alloys are quite light and therefore are commonly used in aerospace and automotive industries, which prioritize optimization of vehicle performance and reduction of fuel consumption. Aside from exhibiting excellent resistance to metal fatigue and corrosion, aluminium alloys also have excellent strength-to-weight ratios and help engineers reduce weight of parts even more with the additive manufacturing’s ability of producing complex geometries.

Significantly reducing lead time for manufacturers

Engineers in different industries have integrated metal additive manufacturing to shorten their production time. Compared to the traditional metal manufacturing processes, such as CNC, casting, and forging, 3D printing is much faster and is capable of producing parts that are as good as or even better than those produced with traditional techniques. Furthermore, metal additive manufacturing can shorten the supply chains by removing several steps, such as assembly, warehousing, and other. As a result, the overall lead time for manufacturers to produce and deliver the metal parts to the customers is significantly reduced.

Printing complex parts as easily as printing simple parts

Metal additive manufacturing can print complex parts as easily as simple parts. Traditional metal manufacturing processes are mostly subtractive, meaning that machines form the final products by removing parts of the materials. It will be quite difficult and time-consuming for traditional processes to produce complex parts. However, metal additive manufacturing fabricates parts by adding layers of materials and therefore printing complex parts is just as easy as printing simple parts for metal additive manufacturing.

Aerospace

The aerospace industry has been incorporating additive manufacturing into its production strategies to take advantage of its flexibility in engineering and design. Airbus has been using metal additive manufacturing to reduce the weight of aircraft to not only decrease the consumption of fuels but also emissions of carbon dioxide. Earlier this year, Boeing 777X took its first flight with more than 300 3D-printed parts from Everett, Washington. With the help of 3D printing and other advanced materials and technologies, Boeing 777X is said to be the biggest twin-engine jet with the biggest engines but also the most fuel-efficient commercial aircraft in the market. From applying additive manufacturing to produce parts of aircraft cabins, engineers in the aerospace industry have now started designing and producing more complex and essential parts for aircrafts, such as engines and turbine parts. 

Automotive

The automotive industry has been one of the main drivers of metal additive manufacturing’s development as manufacturers need to design parts with complex geometries and produce lighter parts to not only reduce fuel consumptions but also improve performance of automotives. Initially, additive manufacturing was mainly used for rapid prototyping. Automotive manufacturers have extended the use of metal additive manufacturing to the production line. In early 2018, Ford and Porsche started exploring the potential of additive manufacturing and even introduced metal additive manufacturing for cooling components. Earlier this year, Alfa Romeo revealed the C39 F1 race car that featured 143 additively manufactured parts that helped the team reduce the weight of the car by 2%. Among the 143 3D-printed metal parts, 58 of them were made of titanium, 19 from aluminium alloy, and the rest from AlSi10Mg, which is another type of aluminium alloy with low weight, good strength, and thermal properties.