GKN Sinter Metals and Porsche Engineering 3D Print with a New Kind of Steel

Share this Article

Steel, particularly stainless steel and tool steel, is a reliable and commonly used material in industries including tooling and biomedical. What is still relatively uncommon, however, is steel material for additive manufacturing. It exists, it’s just not as common as other metal materials – which is a shame as steel has a number of highly useful properties, such as high strength and corrosion resistance. A new steel material recently joined the additive manufacturing market, however, in the form of GKN Sinter Metals‘ 20MnCr5.

20MnCr5 is strong yet ductile, tough yet machineable, and boasts high fatigue strength and wear resistance. Porsche Engineering recently used the material to 3D print components for its e-drive powertrains, namely a conventional front transverse transmission. For optimum benefit, the part with the largest weight reduction potential, the differential housing with a ring gear, was chosen.

The ring gear and the differential housing serve different functions in a conventional transmission. The ring gear is made of specific steel, which is then hardened and ground for precision. The differential housing is usually casted and used for torque transfer from the ring gear to the center bolt and bevel gears. The wide ring gear teeth are supported by a thin, sometimes off-center, disc, which is connected to the differential housing. GKN and Porsche used CAD software and topology structural optimization to design a new shape based on the forces. The maximum available space within the transmission was then defined. All of the inner contours needed for any function, such as bevel gears, side shafts and bearings were subtracted from the body.

Based on the specifications and requirements of the transmission, all loads, including bearing and gear, were applied to the package block. The CAD optimization tool created a structure capable of taking all required loads. The resulting structure cannot be manufactured by any other means than additive manufacturing.

The inner shape is supported only by a system of organic beams and structures necessary for its structural integrity. These shapes cannot be machined by conventional methods. The structure also requires special features like holes to eject the unused metal powder after manufacturing, and openings on the outer diameter so that collected oil can drain in the inner area of the differential. These features can all be planned in the CAD model.

a) Conventional differential of front transverse transmission, b) package model of differential

The final finite element analysis showed a homogenous stress level and allowed wall thickness to decrease, which is not possible with other manufacturing methods due to machine limits. Based on original load requirements, the team was able to decrease weight by 13%, or about one kilogram; they also achieved 43% decrease of tooth stiffness variations in radial direction, 69% decrease of tooth stiffness variations in tangential direction, and 8% reduction of inertia.

Automobile manufacturers are constantly looking for ways to improve vehicle efficiency, whether it’s reducing weight, creating more efficient internal combustion engines, or improving powertrains. More and more of these manufacturers are turning to additive manufacturing to prototype and even manufacture parts, many of them with geometries impossible to achieve with traditional manufacturing. Add that to the materials that additive manufacturing offers, such as GKN’s 20MnCr5, and manufacturers are capable of creating complex, lightweight parts that withstand high wear.

GKN has been exploring the benefits of automotive additive manufacturing, and this recent application highlights several key capabilities of 3D printing. Read the full case study at the GKN Sinter Metals blog.

Discuss this and other 3D printing topics at 3DPrintBoard.com or share your thoughts below. 

[Images provided by GKN Sinter Metals]

 

Facebook Comments

Share this Article


Related Articles

3D Printing News Briefs: May 26, 2019

Patented Metals with Extremely High Carbide Content



Categories

3D Design

3D Printed Art

3D Printed Food

3D Printed Guns


You May Also Like

3D Printing News Briefs: April 28, 2019

We’re getting the business out of the way first, then moving on to awards and rewards in this edition of 3D Printing News Briefs. CECIMO has expressed its approval of...

Big Push in Germany to Enable 3D Printing in Automotive Industry

3D printing and additive manufacturing have become a matter of national importance in Germany, and to the automotive industry overall. Several organizations—along with the ongoing support of the Fraunhofer Institute...

Pushing it to the Limit with the Hoonitruck! Ford Creates Largest 3D Printed Auto Part Ever

Rev up your engines and get those motors racing as we explore the wilder side of 3D printing in the automotive industry. If you are a car and truck or...

Carbon and Ford Expanding Collaboration for Automotive 3D Printing Solutions

Digital manufacturing company Carbon and the Ford Motor Company, which recently announced the opening of its new Advanced Manufacturing Center in Michigan, have revealed that they are expanding their existing collaboration,...


Training


Shop

View our broad assortment of in house and third party products.


Print Services

Subscribe To Our Newsletter

Subscribe To Our Newsletter

Join our mailing list to receive the latest news and updates from our 3DPrint.com.

You have Successfully Subscribed!