Microstructures and Mechanical Properties of a New Low Carbon Bainitic Weathering Steel

A low carbon bainitic weathering steel with Cu-P alloying was developed.The mechanical properties and hot-rolled microstructures of the new steel at different finishing temperatures were investigated.Cu-P alloying produced strong solution strengthening,delayed the transformation of austenite to bainite,thereby increased the amount of M/A islands.The interaction of phosphorous and copper atoms with dislocations inhibited the recovery process and the formation of subgrains.Low temperature rolling promoted the formation of bainite plates and reduced the size of M/A island,which were beneficial to improving the low temperature impact toughness of phosphorus-bearing low carbon bainitic steel.