Effect of Pickling on Notch-Toughness, and Surface Pitting of HY-80/100 Type Steel Plate

摘要

An investigation was made to develop a uniform and improved pickling procedure for the descaling of HY-80/100 type steel plate. The principal governing criteria were (a) maximum depth of pitting and (b) effect on notch-toughness as evaluated by the Navy tear test. Results indicate the following: (a) HY-80/100 steel plate may be pickled in the standard solution for time intervals up to two hours without adverse effects on the material provided that there is at least a 48 hour interval before fabrication. (b) Windrowing or deep furrowing of plate surfaces observed after removal of the steel from the acid bath is associated with the prior mill processing and not the chemical action of the pickling solution. The following modifications in the pickling procedure are recommended for HY-80/100 type steel: a Pickling times up to two hours should be permitted provided that there is at least a 48 hour interval before fabrication (24 hours currently specified). b For intervals of less than 48 hours, rinse time after pickling should be increased to 30 minutes or the plate should be heated at 200F for at least four hours. Consideration should be given to modification of the inhibitor specification to screen out those inhibitors which might have embrittling effects. (Author)