We studied two hybrid technologies and the properties obtained in relation to the applications. For each of these Duplex processes, we also evaluated the benefits from an energy and environmental point of view.

[1].[2]The first hybrid process carried out either in a plasma nitriding system either in a "coating system" is a combination of a plasma nitriding treatment and a DLC tribological coating intended for heavily stressed mechanical components . While obtaining remarkable multifunctional properties, this process is particularly well suited for the energy and ecological transition. We present an example of the potential for "green industrialization" through a hybrid duplex DLC treatment, gearboxes for electric cars compared to the current process.

In addition, the very energetic plasma sources available in a coating equipment allow the nitriding of AISI 316L and 304 stainless steels and to obtain strong S phase growth kinetics [3]. Thus, by associating the characteristics of the substrate with the nitriding properties (S phase) of wear and compression resistance and the tribological properties of a DLC coating, this hybrid process opens up great industrial perspectives.

The second hybrid process studied consists of the association of PVD coating by arc evaporation and magnetron sputtering. The research was conducted in two directions:

• To improve tribological or corrosion resistance properties by associating hard layers with layers or self-lubricating particles.
• To improve biocompatibility and inhibition of bacterial proliferation by associating TiN, ZrN, TiAlN coatings with the addition of copper or silver by co-deposition or multilayers [4]

Hybrid processes, by implementing several technologies in a single piece of equipment, allow for the realization of multifunctional processes. These offer a very strong potential for industrialization not only thanks to the multiple properties obtained, but also thanks to the reductions in CO2 emissions that they allow.