Kingfa has worked in unison with German Tier I supplier Brose Fahrzeugteile to develop its new continuous fiber reinforced material, called KingPly, to fulfil the high requirements set by Brose for a lightweight door module carrier with considerable weight saving targets while not sacrificing on performance requirements. Moreover, Brose managed to increase functional integration.

The partners realized a weight saving of about 35% compared to a standard injection-molded door module carrier and reduced the car weight of the four-door model Ford Focus by more than 1 kg compared to a 30-percent long glass fiber-reinforced polypropylene (PP-LGF) door module carrier. Compared to a standard metal door concept without plastic carrier, this composite design can reduce the car weight by more than 5 kg.

With its new composite materials based on unidirectional (UD) tape layers, Kingfa advances into new areas of lightweight design. Thin single layers made of KingStrong UD tape are used to manufacture custom-made semi-finished products in the form of sheets under the brand name KingPly for the customer, which are finetuned exactly to the application and its requirements.

In the case of the door module, a very thin but strong multi-layer material is fabricated to give the part stiffness and strength. The door module has numerous requirements: Stiffness, strength, NVH, acoustics and also sealing, as the carrier is on the division line between dry and wet within the door structure. The chosen material uses a PP matrix and continuous glass fiber as reinforcement. The sheets are cut by Kingfa to the exact dimensions needed in the injection molding tool, so that no cutting is required, nor waste generated at the customer’s premises.

“Now, even more efficient parts can be designed and manufactured using UD layers, which enable highly custom-made and optimized materials. They can be used even better to implement the lightweight requirements of the future than commonly used similar materials based on woven fibers,” explains Martin Klocke, Vice General Manager Automotive Business of Kingfa Sci.&Tech. (Europe) GmbH, the European subsidiary located in Wiesbaden.

“Our newly developed thermoplastic composite materials have proven Kingfa’s innovative capacity and we hope to even better support our customers in their lightweight projects. To achieve this, we invested heavily in the design and construction of our own in-house technology and manufacturing. The whole production setup was optimized such that we are ready to tackle high-volume mass production. This is proven by this successful mass production project by Brose for Ford.”, says Peng Xiao, General Manager at Guangzhou Kingfa Carbon Fiber Materials Development.

The thermoplastic composite materials from Kingfa can be processed in a single-shot injection over-molding process. The part manufacturer has optimized this process for the mass production of the door module to such an extent that it is able to offer cost attractive lightweight parts in high volume. An important feature of the process is a short cycle time and the fact that forming of the composite and injection occur in the same tool.

The composite material is complemented in the carrier by Kingfa’s pultruded PP LGF injection molding grade. This grade was optimized to match current and future high requirements regarding VOC and odor for interior applications.

Kingfa is confident that its composite materials and compounds can be a solution for many cost-effective lightweight applications in the automotive industry in the future. This will be further demonstrated during K 2019, where Engel will showcase a complex high-tech production cell on their booth with daily live demonstrations. On this machine, a new, innovative part developed by Brose will be produced on a tool made by Georg Kaufmann Formenbau, hinting at the future of door structures. It features three different organic sheets tailor-made by Kingfa. These sheets fulfil very different mechanical and aesthetic requirements within Brose’s part design, which can be met with Kingfa’s UD-based technology.

Finally, the sheets are overmolded with Kingfa’s PP LGF injection molding material which provides the ribbing and also an aesthetic surface. “This application shows not only the future of possible plastic door structures, but also how our own technology will fit into this. On the one hand, we can follow the load paths within the part with our UD fibers; on the other hand, our UD based organic sheets can be overmolded to form an aesthetic surface. This is by far easier with our materials than with currently used, fabric-based organic sheets”, says Dr. Xinyu Fan, Director of R&D at Guangzhou Kingfa Carbon Fiber Materials Development.

Kingfa currently offers a portfolio of UD tapes, random mats and organic sheets mainly based on glass fiber and different thermoplastic matrix materials. For KingPly organic sheets based on PP and polyamide (PA 6) matrix resins are offered for automotive applications, whereas a wider variety of KingStrong UD tapes are available based on PP, PA6, ABS and HDPE,  with applications outside of automotive possible.