People familiar with BMW i3 electric cars must understand that the extensive use of carbon fiber composite materials can be used to achieve car light. But the carbon fiber may not replace the cabin environment and other parts of the part, so the new generation of high-pressure resin transfer molding (or Hp-RTM) was born.

The Cleveland Advanced Design and Manufacturing (ADM) car conference was held from March 29 to 30th at the Huntington Convention Center in Cleveland, where suppliers and original equipment manufacturers will discuss lightweight strategies and transmission efficiency.

Frank Henning, director of the Institute of Composite Materials at the University of Western Canada, the Lloyd Hoffman Project Center, Hp-rtm the report.

HP in Hp-rtm is usually about 120 KPAhigh pressure, the typical epoxy resin base system in the mixture of Catalyst and release agent to facilitate the injection mold uniform molding.

The system includes an enhanced non-woven or non-crimp carbon fiber fabric. This process takes only five minutes in industrial production and is used to make large parts such as aircraft frames and wind turbine blades, and the RTM process takes several hours to a few days.

“We’ve achieved two minutes of cycle time in the development process, and for simple parts that use polyurethane, it can be shortened to one minute,” Henning said. The next generation of materials will be fully implemented in one-minute cycle. ”

According to Henning, developed on the basis of BMWi3 and i8, the use of composite materials can reduce the weight by 50%, and for the BMW8 system, such as the existing design, the use of steel composite mixing method, can reduce the weight of about 20-40%.

According to Henning requirements, if the parts are not over-designed, you can save additional weight. “The parts are still too designed, because OEMs want safety first, so the time to reduce weight and cost is basically ripe, especially when carbon fiber is expensive,” he said.

The resin can be injected into a completely closed die or partially open mold, the latter being called compression RTM. Compression RTM is generally more suitable for the formation of larger components, but during the resin permeation phase, fibers tend to migrate and shift. So the simulation experiment can minimize these effects.

Five years ago, the Fraunhofer Institute in Germany established the Fraunhofer Project Center (FPC) at the University of Western Canada, becoming the largest composite manufacturing center in North America, with an industrial scale.

Research and development focus on the automotive industry, FPC can create a complete car structure, including roof, base, side frame, seat, and tail door.

In addition to RTM, FPC is also capable of processing sheet-shaped compounds (SMC), long fiber reinforced thermoplastic plastic and manufacturing composite foams.

The latest research is to install a fast-placed unidirectional hot plastic belt. “In this way, we are using thermoplastic and thermosetting resins, as well as discontinuous and continuous fibers.”

A similar center is being opened next year in South Korea’s Ulsan, and the third center in Jiangsu, China, is in the planning stage, Henning said.