Spare parts for trucks and buses made in a 3D printer

Trailblazing future technology.

Mercedes-Benz Trucks and Daimler Buses are pioneers in the supply of 3D parts.

Genuine parts for Mercedes-Benz Trucks and Daimler Buses as well as for vintage cars and late-model classics that can be ordered and supplied even after many years - in the parts business they are already reality and have been for a long time.

Now comes the next step: The first plastic series-production parts made using additive manufacturing technology have been in use since 2016 in, among others, our commercial vehicles division and in special-purpose vehicles such as, e.g. the Unimog. Today, customers can order a double-digit number of parts for Mercedes-Benz Trucks out of the 3D printer in any desired quantity, "at the touch of a button," so to speak.

The Buses division nowadays also uses this technology to produce special customer options, and as part of the CSP 3DD (Customer Services & Parts 3D Print) project conducts in-depth reviews to determine which parts are suitable for being manufactured using the 3D printing process.

The available special parts and spare parts are made from high-grade plastic components. covers, spacers, spring caps, air and wiring ducts, brackets and mountings are some examples.

Last powder particles are being removed.

The parts are manufactured on state-of-the-art 3D printers based on the selective laser sintering (SLS) printing process. This generative layer manufacturing process involves using a laser to create the physical structures of the pre-programmed 3D part from the powdery polyamide source materials layer by layer.

To ensure the high quality standards of Mercedes-Benz Trucks, the process parameters were optimized and specified by the Daimler Research and Advance Engineering units. They were translated into a Daimler standard to be applied throughout the Group and therefore also in the Buses division.

Based on these parameters, Trucks Parts Engineering reviews the existing range of spare parts for a possible transition to the "generative production process." The same review is simultaneously being conducted for bus parts in the CSP 3DD EvoBus project. This would make it possible to eliminate, e.g. tooling costs for low-demand parts, and ensure the parts availability for "years" to come. Once all requirements on a part are met, the 3D spare part is approved with a specific part number in the parts team and can then be ordered by customers worldwide.

Daimler is also working together with partners on a application for aluminum components in metal 3D printing. A first printed aluminum component for Trucks is already available as a spare part.

Advantages through secure parts supply, fast delivery capability, and economic efficiency

The eco-friendly and resource-conserving 3D printing process plays a pioneering role in the special parts and spare parts business. This process enables Daimler to ensure the parts supply for model series that are no longer in production as well. As a result, our product range also includes parts with only a limited demand each year. Parts whose production is increasingly uneconomical – frequently requiring production facilities and tools to be preserved and maintained for years. The 3D printing process makes these challenges a thing of the past, because each 3D part is quickly available on demand worldwide.

After receiving the design definition and the order, the printing can be done promptly. This makes the parts manufacture and delivery significantly faster. Because spare parts and retrofit parts can be "reprinted" easily even after a long time based on the stored data, they can be delivered without maintaining a costly inventory, thus also eliminating the need for warehousing. At the same time, this saves costs while protecting resources and the environment, because the process creates virtually no excess material that must be recycled or disposed of at great expense and effort.

How 3D printing works:

The 3D printing process involves the layer-by-layer construction of three-dimensional parts. The buildup from one or several liquid or solid materials to the specified dimensions and shapes (CAD) is computer-controlled. Physical or chemical hardening or melting processes take place during the buildup. Typical materials for 3D printing are plastics, synthetic resins, ceramics and metals.

The most important technologies of 3D printing are selective laser melting (SLM) for metals and selective laser sintering (SLS) for plastics.

Selective laser melting and selective laser sintering both involve applying the powdery material to a substrate plate. The layers are sintered or melted into the power bed gradually. The substrate plate is then lowered slightly and a new layer is applied. The powder is supplied by raising a powder platform. The processing takes place layer by layer, making it possible to create complex structures.

In the selective laser sintering (SLS) process, the plastic powder is heated to about 90 degrees Celsius before melting. It changes its characteristics already before being exposed to the laser. The melting point of the material used by Daimler is about 175°C. The laser fuses the individual layers into a three-dimensional component, which during its formation is always supported by the surrounding powder.

The temperature of the assembly space is far below the melting point of the material during selective laser melting (SLM). The laser energy melts the material wherever it is hit by the laser.