ZOLTEK Corporation Sheet Molding Compound

ZOLTEK, together with Toray, has developed a new innovative technology and input material for Sheet Molding Compound (SMC) for compression molding. SMC is a material consisting of resin and chopped carbon fiber which is placed into matched metal tooling to mold a finished part.

The new carbon fiber tow product still consists of a large tow (50K), but it is now split into 3K sub tows, so that when chopped it breaks apart into a homogeneous isotropic bed of small tow carbon fiber which is easily wet out in the SMC process. The resulting molding compound produces a revolutionary strong and stiff composite part suitable for automotive and other applications.

Final parts molded from SMC benefit from a high throughput compounding process coupled with low cost inputs (resin and fiber). Further, the molding process is highly efficient with very low waste. More than 97% of the compound is used in the final molded part with very little edge trim or other scrap.

Typical Properties - Cut Coupons, Average 0/90:
Specific GravityASTM D792g/cm31.41
Tensile ModulusASTM D638GPa34.0
Tensile StrengthASTM D638MPa217
Flexural ModulusASTM D790GPa27.6
Flexural StrengthASTM D790MPa432
Impact Strength N -IzodASTM D4812J/m483
Glass Transition by DMAASTM 7028°C (Tan Delta)>192
Water AbsorptionASTM D570%<0.30
ShrinkageASTM D6289&0.01
FlammabilityUL 94HB

ZOLTEK Corporation Sheet Molding Compound Applications

ZOLTEK PX35 is the dominant carbon fiber in the wind turbine industry and is on the forefront of many other applications including infrastructure, automotive, pressure vessels, offshore drillings, and other industrial applications. It is the best value proposition of any other carbon fiber with market-leading properties at a market-leading price.