Erosion problems are common in pneumatic and hydraulic systems due to the action of the processed mean. Sometimes this issue can be faced with design refinements changing the system at a base level. On the other hand, when design changes are not possible or not enough for preventing the problem, the selection of the proper material is of main focus. The objective of this activity has been to improve the lifetime of a spindle undergoing strong erosion during operation.

This study proposes the assessment of impingement erosion and electrochemical corrosion resistance of two coatings materials deposited by Cold Spray technology and compare them to 440C annealed steel. The tested coating materials were CrMnFeCoNi and WC-Ni, deposited on 2205 duplex stainless steel substrates using nitrogen as process gas. In between the substrate and the high entropy alloy coating, an interlayer coating of 316 stainless steel was used to enable HEA adhesion. The presence of WC particles in the WC-Ni composite coatings was confirmed by SEM cross sectional inspection. Following deposition, the coatings were heat treated in an air furnace. The influence of heat treatment holding time on the WC-Ni coatings was studied using chemical analysis by x-ray diffraction. Heat treatments peak temperatures for the WC/Ni-Ni and high entropy alloy coatings were 600°C and 550°C, respectively. Coatings microhardness and porosity volume fraction were measured for all the samples. The HEA coating outperformed the WC/Ni-Ni hardness but exhibited a higher level of porosity. Both the coatings and 440C plates were then subjected to erosion experiments using alumina particles with variable impact angles (30°, 60°, and 90°). To compare the different materials, an average erosion value was calculated for each target specimen. The WC/Ni-Ni as-sprayed coating was the most effective coating against a 60° impingement angle. The HEA coating, on the other hand, demonstrated greater resistance to impact angles of 30° and 90°. However, the 440C substrate seems to be more resistant to particles impingement. Cyclic Potentiodynamic tests were also conducted on the three different materials and the 440C showed the highest corrosion rate. In this study the Selective Laser Melting processing of 316 stainless steel and Maraging steel was conducted. Optimal parameters were defined by DoE approach and the mechanical behaviour of the manufactured parts was tested.