Improving the Erosion Behavior of Steel and Aluminum Substrates by Heat Treatment and Titanium or Zirconium Nitride Multilayer Coatings

Erosion caused by the impingement of solid particles carried by a fluid onto metallic surfaces is a common problem for equipment working in aggressive environments. The erosional process is influenced by the particles size, intensity, angle of impact, and the surface properties of metal. The erosion process was investigated for aluminum and steel alloys before and after performing the corresponding heat treatment. The substrates were also coated with micron size titanium or zirconium nitride multilayer structures using the DC high vacuum magnetron sputtering deposition equipment and their performance was evaluated. The coatings’ thickness was in-situ monitored using a quartz crystal microbalance and ex-situ evaluated using a profilometer. The chemical composition of the structures was characterized using the X-Ray diffraction analysis and scanning electron microscopy/ energy dispersive X-ray spectroscopy (SEM/ EDS) techniques and their surface morphology was obtained using the scanning electron microscopy (SEM) system. All samples were evaluated by a custom designed erosion apparatus using different intensities and angles of impact in order to optimize the coating composition and thickness for the best erosion behavior.