weighed they were then suspended from a glass rod in a salt spray cabinet for a total of 240 hours in accordance with astm b117 standard procedures the position of the panels was shifted periodically to ensure uniform exposure after exposure the panels were cleaned according to astm g1 standard procedures each panel was rinsed with distilled water dried and cleaned of adherent corrosion products by immersion in hot 20 chromic acid plus 1 silver nitrate for 1 to 2 minutes the panels were quickly dried and reweighed the corrosion rate in mils per year mpy was calculated with equation 1 as outlined by the astm g1 standard data from this study were combined with those reported in the sae technical papers previously identified by combining these two investigations a single comprehensive data matrix consisting of 83 corrosion test panels was created table i sets out the range of compositions and corrosion rates in the combined data matrix table i______________________________________ investigated rangestudy parameter from to______________________________________current nickel 0 0001 0 0014 copper 0 0001 0 0115 iron 0 0011 0 0162 fe mn 0 0076 0 0383 corr rate mils yr 0 4 40 0 no of panels 53hillis et al nickel.