Use of inkjet printing to deposit magnesium chloride salt patterns for investigation of atmospheric corrosion of 304 stainless steel

Inkjet printing was used to deposit MgCl2 salt patterns on 304 stainless steel foils to investigate atmospheric corrosion. Results were found to be more consistent if initial hydration (1 h at ∼90% RH) of the printed salt pattern was carried out. The pit diameter following exposure at 45% RH and 300 K for 24 h was found to increase with the diameter of the original salt deposit, which is consistent with the idea of cathodic limitation of the pit current. For a constant deposition area, the pit diameter increases with increased salt deposition density, which may be associated with a lower ohmic drop resulting from a higher droplet, or could be influenced by enhanced corrosion during the initial hydration stage.

► Inkjet printing of MgCl2 salt patterns was shown to be an effective method for studying atmospheric corrosion of stainless steel.
► Pit diameters were found to increase with the diameter of the salt pattern and the salt deposition density.
► The method can be adapted for combinatorial measurements of salt composition as well as the size and shape of the deposits.