4.4.7 Microwave Plasma Processing of Metals
Microwave plasma processing has been applied extensively for thin film applications and
ceramics processing [103–105]. Typical plasma applications include etching, deposition/
coating and surface treatment for thin films and sintering, bead and fiber production in
ceramics [103–105].
Microwave plasma processing has also been used for the surface treatment of metals [106,
107]. Microwave plasma nitriding of AISI-316 stainless steel was performed to determine
the optimum H2/N2 ratio for the nitriding process [106]. From the study, it was found that an
optimum ratio of 60 % H2/40 % N2 increased the surface hardness from 260 Hv to 1000 Hv
and improved the corrosion rate from 588:6 103 mpy to 309:6 103 mpy [106].
In a recent study, researchers have shown that it is possible to modify the surface of an
aluminum sample using microwave plasma at atmospheric pressure to improve the surface