Low deposition temperature PVD coatings can be deposited at temperatures below 500 deg.C. Allowing bearing steels, and titanium or aluminium alloys to be coated for example. The temperature can even be reduced to a level that polymers can be coated.
Smooth coatings Magnetron sputtered coatings follow the exact surface roughness of the substrate material. If a fingerprint was present before coating you will see it after coating. Low surface roughness reduces heat generation in applications such as machining.
Hardness PVD coaings are deposited while under concurrent ion bombardment. These energetic ions allow the deposition of dense, hard films by supplying the sputtered neutrals with sufficient energy to find a suitable nucleation site and inducing high compressive stress. Coatings with a hardness of 1000-4000HV are possible with this technique, approximately 5x the hardness of tool steel.
Wear resistance PVD coatings can be deposited that are resistant to all forms of wear. In machining for example substantial reductions in the following are oberved:
Problem: Crater wear (chemical interaction between the tool and the workpiece).
Solution: Stable coatings that do not readily chemically react.
Problem: Flank wear - abrasive wear by hard constituents of the workpiece.
Solution: Hard coatings
Problem: Built-up at the edge - welding of the workpiece material to the tool tip which may detach along with part of the tip.
Solution: Low friction coatings that reduce heat generation and the formation of solid solutions.
Problem: Depth of cut notching - oxidation of the tool material with some abrasion from the edge of the chip.
Solution: Coatings can be deposited that resist oxidation up to 1000 deg.C.
Problem: Thermal cracks - produced by temperature gradients in repeated heating and cooling in interrupted cutting
Solution: Low friction coatings that reduce heat generation.
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