Combined deep drawing and compression molding process for producing metal-plastic hybrid components using VESTAMELT Hylink
The goal was clearly defined: to come up with high-performance manufacturing processes that would reduce the weight of metallic chassis components. The result: weight savings of about 20 percent in two different automotive control arms. This was achieved thanks to adhesive bonding between metal and a long-fiber-reinforced thermoplastic (LFT) by the adhesion promoter VESTAMELT Hylink. The multiform process for simultaneous forming and molding of fiber-reinforced plastics with metal plates is used here.
*The longitudinal control arm made of high-strength steel plate and VESTAMID PA12 with 40 percent long glass fibers substitutes the solid metal part, reducing the weight by about 20 percent. *
Composite compression molding process
The metal and plastic components of hybrid parts are typically bonded with the help of frictional or form fit elements such as screws, rivets, or by overmolding and insert molding. The challenge in the case at hand was to come up with a novel production process that includes the forming of the metal plate as well as the molding of the long-fiber-reinforced thermoplastic, taking into account reinforcement ribs and a variable wall-thickness distribution of the fiber-reinforced plastic (BMBF: Multiform 02PN2081). For this process an adhesive bonding technology such as is offered by VESTAMELT Hylink is an absolute necessity.
The longitudinal and transverse control arms of the car rear axle of a well-known German car manufacturer served as demonstration components; originally made from solid metal, these were now produced by the multiform process. Subprojects on the design, simulation/computation, and testing of components made from a novel FRP metal composite material were carried out under the guidance of Prof. X. Fang at the University of Siegen. From these, and the subsequent process development, a new solution was developed consisting of a high-strength steel plate and a long-glass-fiber reinforced thermoplastic that are bonded with the adhesion promoter VESTAMELT Hylink. For demonstration purposes, for example, a polyamide 6, polyamide 610, and polyamide 12 with 40% long glass fibers were used in a longitudinal control arm.
In the multiform process a long-glass-fiber reinforced compound produced by Weber Fibertech GmbH is extruded to give a moldable semi-finished product. Together with a preheated metal plate coated with VESTAMELT Hylink this is transferred in the molten state into a mold. In a one-step production process both parts are pressed into shape and simultaneously joined together. The mold incorporates the desired negative form for the ribbing and the forming of the metal. Thanks to the process-integrated bonding of steel and LFT by VESTAMELT Hylink, a bonded hybrid component can be obtained directly from the mold. This method could be a technical and economical substitute for the conventional multi-step production process.
By combining steel and LFT, materials of two different types (two dissimilar materials), it has been possible to reduce the thickness of the steel plate by more than a millimeter from the original. This results in about 20 percent less total weight of the demonstration longitudinal and transverse control arms.
Further information from: www.evonik.com
New Redi-Spine system for spinal fusion surgical procedures from Innovative Surgical Designs
Solvay, a leading global supplier of specialty polymers, announced during NASS 2018 recently that Innovative Surgical Designs, a developer and manufacturer of orthopedic spinal systems, chose Ixef polyarylamide (PARA) resin to innovate a new single-use surgical instrument kit for minimally invasive spinal fusion surgery. Innovative Surgical Designs' new Redi-Spine kit leverages Ixef PARA's mechanical strength, moldability and gamma sterilizability to offer an economical alternative to reusable stainless steel instruments.
“Ixef PARA's metal-like strength and rigidity enabled us to simplify and deliver Redi-Spine instruments in a compact, elegant kit,” explained Jon Rinehart, chief financial officer of Innovative Surgical Designs. “When we first started heading down the path of polymer instruments, I candidly admit that I was skeptical. I didn't think an injection-molded alternative to stainless steel was possible. But when we started working with Solvay's Ixef PARA resin, I realized how wrong I was. We wouldn't be able to offer the Redi-Spine kit for all of our surgeons' one- and two-level cases without Solvay's high-performance polymer and application support. ”
Designed to withstand the severe torsional forces and rigors of thoracolumbar spinal fixation, Innovative Surgical Designs' Redi-Spine instruments received 510(k) clearance from the U.S. Food & Drug Administration (FDA) in August. It contains multiple disposable, handheld instruments including a T-ratchet handle, countertorque tool and gearshift probe that are molded entirely or in part from Solvay's Ixef GS-1022 PARA.
Ixef GS-1022 PARA can be sterilized with gamma ray radiation without any significant change to its mechanical properties, ultra-smooth finish or color. Solvay offers the material in a range of gamma-stabilized colors, from which Innovative Surgical Designs, Inc. chose gray for its kit. Solvay's polymer has also been evaluated for ISO 10993 limited duration biocompatibility and is supported by an FDA Master Access File, which can help streamline regulatory approvals.
“The growing adoption of single-use surgical instruments has increasingly established Solvay's Ixef PARA as a mainstream material for these applications,” said Jeff Hrivnak, business manager for Healthcare at Solvay's Specialty Polymers Global Business Unit. “We continue to build on our early and proactive support of this trend by working closely with trailblazers like Innovative Surgical Designs, Inc. to help optimize their products for molding and speed to market.
Further information from: www.solvayhealthcarenews.com.
New Geon Plenstar series for telecommunication cables launched at IWCS
PolyOne announced availability of the new Geon Plenstar series of fire-resistant, plenum cable jacketing at the recent IWCS International Cable & Connectivity Symposium.
Answering the market need for flame retardance and low smoke performance, the Plenstar series includes five grades of cable jacketing materials. All meet UL approvals for plenum applications and provide the robust physical properties required for telecommunications cables.
“The Geon brand has a long history of supplying vinyl solutions in the wire and cable industry,” said Jim Mattey, global marketing director, Performance Products and Solutions, at PolyOne. “We are excited to provide multiple grades of plenum materials supported by our unsurpassed regulatory, processing and material science expertise.”
Addressable applications for the Plenstar series are Cat 3 to Cat 6 multi-conductor cables with a 75°C UL temperature rating, passing UL 444. Customization is possible for modified performance enhancements as needed, and custom colors can be developed as well.
Further information from www.polyone.com.