Škoda has put a new processing line for plasma coating into operation. The process allows conventional cylinder liners to be replaced with a powder coating that measures 150 μm (0.15 mm). This will now be used when producing the company’s EVO three-cylinder engines from the EA211 series. The process will reduce internal friction and, as a result, the company says the 1.0 TSI EVO petrol engines will be even more efficient and boast even lower emissions.

During production, the cylinders are first bored on the machining line. A 1,500-watt laser then abrades the cylinder bores to ensure the plasma layer will adhere to the surface.

A mixture of hydrogen and argon is then used to create plasma gas which is mixed with various types of steel that have been ground into fine powder. This powder is made up of iron, carbon, silicon and manganese as well as other elements. When sprayed onto the cylinder walls, the molten powder forms a layer measuring approximately 250 μm which is then honed out to measure 150 μm.

Optical measuring instruments first record the surface abraded by the laser, before a second measurement is taken once the plasma has been applied. Finally, the structure of the plasma layer is tested using turbulent flow.

Source: Motor Trader E-magazine (October 2020)

12 October 2020