Let’s kick off our newsfeed with very exciting news: Ducati introduces lightweight motorcycle seat support rear frame!
Mitsubishi Chemical Europe. Has displayed a lightweight motorcycle seat support rear frame developed through joint R&D between MCC subsidiary, Gemini Composites, and Ducati Motor Holding in October 2019 at the K Show, and again earlier this year in May 2022 at JEC World.
The seat support rear frame comprises the entire aft frame of the vehicle, forming an integral part of the chassis. It is designed based on fatigue strength criteria, but also must meet stiffness, static strength, and finish requirements. The part developed replaces a cast aluminum component for the Ducati Hypermotard 939, a vehicle designed for both road and off-road racing, and constitutes the main structural support for the driver, and optionally passenger and cargo bins.
The rear frame is made from MCC’s forged molding compound (FMC) material, said to be an advanced version of carbon fiber sheet molding compounds (CFSMC) and, combined with a modified molding process and a dedicated design philosophy, is said to be capable of yielding parts with properties suitable for primary structural applications.
The forged composite part weighs 0.8 kilograms, while the aluminum one is typically 1.35 kilograms per side, which represents a total savings of 1.1 kilogram, while maintaining the same cost and rate targets for the baseline aluminum component. The total motorcycle weight is 167 kilograms.
Now, let’s talk about 3D printing of composite materials! We have selected two news that cover groundbreaking projects!
Low-void, large-scale, high-volume 3D-printed composites!
Among its many composites-related projects, Oak Ridge National Laboratory recently installed its first AMCM test cell, combining extrusion with compression molding for fast, low-void, low-porosity thermoplastic composite parts.
AMCM has been in development for more than two years, and the team originally began by using the MDF’s existing large-format BAAM printer and compression press. Using this setup, ORNL was able to demonstrate initial benefits to the process combination such as low voids in the final part. However, the machines were not next to each other, and the relatively short distance of travel between the BAAM and press required an additional reheating step in a belt oven prior to compression molding to soften the preform again to the correct glass transition temperature (Tg). These five to six extra minutes of preheating per part significantly increased the overall cycle time up to eight to nine total minutes per part, says Dr. Vipin Kumar, R&D associate staff member in ORNL’s Advanced Composites Manufacturing group.
It quickly became apparent that a dedicated production cell that combines AM and compression molding into one system would be needed to demonstrate that this technology could be used in a high-volume production environment,
To produce a part in the AMCM cell, the part geometry is extruded directly onto a mold, resulting in a 3D tailored preform that travels via conveyor belt directly into the press for immediate molding (see video below). Kumar explains that the material is extruded at, or a little above, the melting temperature of the material, and that the design of the AMCM cell allows the preform to reach the press for compression before the material has cooled down below its Tg.
Interested to know more about this project? Check out this link:
High-performance, high-detail continuous 3D-printed carbon fiber parts!
Mantis Composites Inc.’ new technology uses a fused filament fabrication (FFF) 3D printing system, which essentially entails extruding a filament made up of a pre-impregnated, continuous fiber/towpreg. The company also developed its own specialized design software to model and print parts with the accuracy needed to create detailed components to meet aerospace specifications. Parts can be printed on a range of commercial materials, though Dunn notes mostly carbon fiber and high-temperature thermoplastics like polyetheretherketone (PEEK) are used.
Today, operating three additive manufacturing (AM) cells with a maximum print volume of 18 x 20 inches, Mantis Composites offers custom design/engineering, printing, postprocessing, bonding and surface treatment services for each of its projects. Fiber placement accuracy is said to be within ±0.015 inch (±0.4 millimeter) tolerance, and lower after postprocessing such as machining or sanding.
Our last story is about dimensional issues in high-temperature cured laminates!
When it’s not the tooling, the root cause of dimensionally inaccurate composite parts often boils down to two things: fiber form(s) used and laminate symmetry!