The Heavyweight of Engineering Polymers
When consumer plastics melt or deform under thermal load, Polycarbonate (PC) is the standard upgrade. Renowned as the polymer used in bulletproof glass and riot shields, PC delivers a glass transition temperature of 145-150 °C and heat deflection under load exceeding 110-120 °C.
In addition to thermal resistance, PC possesses remarkable flexural yield strength (~90 MPa), allowing structural brackets to take immense bending stress without permanent plastic deformation.
Overcoming the Warping Challenge
PC has one of the highest thermal contraction coefficients among commercial 3D printing filaments. Attempting to print PC on an open-frame printer or with an unheated chamber will result in violent corner lift, glass bed delamination, and cracked layers.
- Hotend Temperature: 280 °C to 310 °C (all-metal hotend required).
- Heated Bed: 110 °C to 125 °C coated with Magigoo PC or PVP glue stick on textured PEI.
- Actively Heated Chamber: A passive enclosure at 55 °C is the bare minimum; an actively heated chamber at 65-80 °C is ideal for parts larger than 100 mm.
PC Blends: PC-PBT and PC-ABS
To reduce warping while maintaining thermal headroom, chemical blends like PC-ABS offer a practical compromise. PC-ABS prints 15 °C cooler than virgin PC, exhibits smoother surface aesthetics, and retains 80% of PC's impact toughness.
