These processes allow to deposit some coatings in order to optimize the working and reliability of some mechanic components, when thermal processing  (temper etc.), thermal chemical ones (cementation, nitridation, etc) or more traditional coatings look improper. This technology is often employed also to restore or repair strongly worn parts, without creating deformation and variation of structures of basic material.

Thermal spray processes consist in a coating obtained from powders whose sizes vary  between 1 and 500µm, wires, metallic sticks, ceramics or cermet (dispersion of ceramic phases in metallic matrix) which are heated in gas atmosphere at high temperature, close to fusion point and then accelerated, in gas emission, towards the substrate where they fast solidify giving place to superimposed lamellar structures (splats).

Zocca Officine Meccaniche, since its foundation, has been protagonist of significant technological turns in this sector:

• Since 1967 we have been realizing metallic coatings such as molybdenum, copper and aluminium alloys, carbon steels, stainless steel, etc. by “Wire Flame Spray” process
• Since 1975, by APS “Air Plasma Spray” process, coatings have been made of molybdenum of nickel basic alloys, cobalt, alloy steels and non alloy steels, bronze, etc of ceramic material based on alumina, cromia and zirconia, of cermet (metal-ceramic composite materials), such as chromium and tungsten carbide, cermet (metal-ceramic composite materials), etc.
• Since 2002 coatings of multi-composed metal alloys have been made, by HVOF (High Velocity Oxygen Fuel) process, particularly of metallic matrix composites (ex. WC – Co). The high speed of gas and particles (faster than 2 Mach) gives the coating adhesion, cohesion, porosity, hardness, etc. values which are neatly superior to those concerning the coatings realized in APS.
• Since 2008 a new torch APS, named Triplex, has been introduced, named Triplex, allowing us to set up the same coatings typology of the traditional plasma torches produced previously, but with neatly superior quality characteristics (both mechanic and composition). By adopting proper tactics it also allows to realize coatings made by metallic matrix composites with a supersonic gas and particles speed (superior to 1 Mach)

Coatings are made on simple and multi-complex geometrical parts by means of ABB robots endowed with absolute check on 7 axes and on completely automated plants.

The best fitting coating for a mechanic part is chosen between a wide range of possible coatings according to whatever stress, strain, wear and corrosion the part is to undergo and by considering the contact surface characteristics of the antagonist component, such as hardness and geometrical shape, and even type and structure of materials.

Zocca Officine Meccaniche realizes coatings having high superficial hardness, best adhesion, least porosity, regular structure, and final thickness and roughness carefully checked. These coatings characteristics allow to reach good results in wear resistance, control of corrosion produced by acid and basic liquids, high work temperatures, thermal shocks (even repeated) and, when required,  best electric insulation.

Present technologies in Zocca Officine Meccaniche:

• Wire Flame Spray
• Air Plasma Spray
• HVOF