The corrosion and erosion-corrosion resistance of several stainless steels and aluminum alloys in strong nitric acid in the temperature range of room temperature to 160 F were investigated. In general the stainless steels show a marked increase in corrosion with increasing temperature. Galvanic couple systems of aluminum and stainless steel show the stainless steel to be protected by the aluminum which acts as a sacrificial anode in strong nitric acid. Polarization studies on aluminum and stainless steel provide some interesting information concerning the corrosion behavior of the aluminum-stainless steel couple system.
Erosion-corrosion tests show that the rate of attack on stainless steel decreases with increasing velocity of acid flow; the rate of attack on aluminum tends to increase with increasing velocity of acid flow. Experiments were conducted on both rotating specimens and on stationary specimens in a system involving a flowing solution.
A detailed description of the equipment used for the polarization and the erosion-corrosion studies is included.
