... seawater. Because of this, it is used for piping, heat exchangers and condensers in seawater systems, ... as well as marine hardware, and sometimes for the propellers, crankshafts and hulls of premium tugboats ... manganese and 2% iron alloy was introduced for a UK power station which needed better erosion ... first became available in the 1950s, initially for seawater piping, and is now the more widely used ...