Extrusion and plasticizing screws that are exposed to abrasive particles containing plastics such as glass fibres, should at least be hardened or nitrided. However, these surface treatments do not offer improved non stick effects, tarnishing and corrosion resistance or are still not enough resistant to wear. In some cases (partially) full ceramic screws are available. Lunac 2+ now opens the
possibility to practically transform a current steel screw into a ceramic screw, yet preserving the characteristic toughness of steel. Another important plating characteristic is the, for a hard coating almost unparalleled, good throwing power in the deep structures (usually 6 times better than that of hard chromium). Thick (crack free) coatings of more than 120 µm / 0.0047" thickness can be deposited.
Extrusion screws prove to perform well over a long period in glass fibre or chalk filled (corrosive) plastics, due to the good corrosion and abrasive wear resistance of Lunac 2+ (up to 7.5 times longer service life compared to hardened DIN 1.2379 steel per µm). The good throwing power of this coating in the deep structure is typical for Lunac:
>120 µm / 0.0047" in the deep structures vs.
>160 µm (0.0063") near the flight tips.
Lunac 2+ offers significant non- stick effect as well.