1. A carbon steel test specimen has a dimension of 2 in x 3 in x 0.125 in with 0.25 in diameter hole. It was exposed in an acid solution for 120 hours and weight loss was determined to be 150 mg. Please calculate the corrosion rate in mpy, pm/y, and mdd. What is the ranking of this carbon steel in this acid environment?
(neglecting all the edge areas, carbon steel density is 7.86 g/cm3)
2. The above carbon steel is also subjected to a planned internal test program at the same time. One specimen is exposed for 12 hours and loses 25 mg. A second is exposed for 108 hours and loses 130 mg. The fourth is inserted in the acid solution when the second is removed. After removal with the third specimen together after 120 hours, the weight losses of specimens No. 3 and No 4 are 150mg and 15 mg, respectively. Determine the effect of time on the solution corrosiveness and the carbon steel corrodibility.