PC carbonate turning and milling

Polycarbonate is a durable material. Although it has high impact resistance, it has low scratch resistance. Therefore, hard coatings are applied to polycarbonate eyeglass lenses and polycarbonate exterior automotive parts. Polycarbonate has properties comparable to polymethyl methacrylate (PMMA, acrylic), but polycarbonate is stronger and holds longer at extreme temperatures. Polycarbonate is highly transparent to visible light and transmits light better than many types of glass.

Polycarbonate has a glass transition temperature of about 147°C (297°F), therefore, it gradually softens above that point and flows above about 155°C (311°F). Tools must be kept at elevated temperatures, typically above 80°C (176°F), to produce a strain-free and stress-free product. Low molecular weight grades are easier to mold than high molecular weight grades, but as a result they are less strong. The most difficult grades of steel have the highest molecular weight, but are much more difficult to machine.

Unlike most thermoplastics, polycarbonate can withstand large plastic deformations without cracking or cracking. As a result, they can be machined and formed at room temperature using sheet metal techniques such as bend brakes. Even for sharp elbows with small radii, heating may not be required. This makes it valuable in prototyping applications that require transparent or non-conductive parts that cannot be made from sheet metal. PMMA/acrylate, similar in appearance to polycarbonate, is brittle and cannot be bent at room temperature.

The main conversion technology of polycarbonate resin:

Extrusion into tubes, rods and other profiles, including multilayer

Extruded from cylinders (calenders) into sheets (0.5-20mm (0.020-0.787in)) and films (under 1mm (0.039in)), which can be used directly or by thermoforming or secondary processing Other shapes are made by techniques such as bending, drilling or milling. Due to its chemical nature, it is not conducive to laser cutting.

Injection molded into finished product

Polycarbonate may become brittle when exposed to ionizing radiation above 25 kGy (J/kg).