Carbon-fiber-reinforced plastics are very much in demand as lightweight construction materials for high-stress components in the automotive, sport and leisure industries, for example. LANXESS is accompanying this trend with new material developments, focusing on thermoplastic systems. One example of this is the new easy-flowing polyamide 6 Durethan TP 038-001 (in the future to be named Durethan BCF 30 H2.0 EF), which is reinforced with 30 percent by weight carbon fibers. Its strengths are its high tensile modulus and tensile strength at break combined with a comparatively low density. “Our high-tech compound is especially suitable for high-stress components that have to be particularly lightweight or thin-walled because of small installation spaces, and at the same time extremely stiff and strong. In many cases, we see it as a lightweight, high-performance alternative to metals, thermosetting plastic systems and sheet molding compounds,” says Dr. Guenter Margraf, expert in Durethan product development.
Good potential uses include lightweight structural components for automobiles or the manufacture of tennis, badminton and squash rackets, for example. Other possible applications include back-injecting of TEPEX continuous-fiber-reinforced thermoplastic high-performance composites made by LANXESS subsidiary Bond-Laminates.
As hard as die-cast aluminum
The new injection molding compound has a density of just 1.262 g/cm3. Nonetheless, at around 11,500 MPa and 140 MPa respectively, its tensile modulus and tensile strength at break in a conditioned state are only slightly lower than Durethan DP BKV 60 H2.0 EF, which is highly reinforced with 60 percent glass fibers and is a cut above other polyamide 6 grades in terms of stiffness and strength. The “weight-adjusted” specific stiffness of the new compound is 9 GPa/g/cm3, similar to the glass-fiber-reinforced polyamide 6. However, at 111 MPa/g/cm3, the specific strength is significantly better. “Our carbon material is approximately twice as strong as most commonly used steel and die-cast zinc materials, and is on a par with die-cast aluminum in terms of strength,” explains Margraf.
Balanced characteristics profile
Furthermore, the material shows good impact strength and notched impact strength both at 23 °C and at -30 °C in the Charpy test (ISO 179/1eU and 1eA). This performance profile is achieved in other mechanical properties such as flexural strain and elongation at break with a justifiable, low level of compromise. Thermal stabilizing ensures that the new material is thermally resilient up to 140 °C.
LANXESS focus on carbon-fiber-reinforced thermoplastics
Until now, the market has primarily used carbon-fiber-reinforced thermosetting plastics for example in bodywork parts for automobiles. LANXESS, on the other hand, is committed to thermoplastic carrier plastics for carbon fibers. “In our experience, such systems are easier to process with lower energy consumption, open up greater design flexibility and produce finished components that do not require reworking and generally weigh less,” says Margraf.
LANXESS (lanxess.com) is a leading specialty chemicals company with sales of EUR 9.1 billion in 2012 and roughly 17,400 employees in 31 countries. The company is currently represented at 50 production sites worldwide. The core business of LANXESS is the development, manufacturing and marketing of plastics, rubber, intermediates and specialty chemicals. LANXESS is a member of the leading sustainability indices Dow Jones Sustainability Index (DJSI) World and FTSE4Good as well as the Carbon Disclosure Leadership Index (CDLI).