IMPROVING STRENGTH AND FRACTURE TOUGHNESS OF MICROALLOYED MEDIUM CARBON STEEL - AN EXAMPLE OF MICROSTRUCTURAL DESIGN

摘要

A microstructural design approach was used to develop thermomechanical processing (TMP) schedules for microalloyed medium carbon forging steels. The TMP forging schedule for a 1541+T,V steel produced recrystallized austenite, and a refined grain-boundary feirite+pearlite microstructure. The TMP schedule for a 1541+Nb steel produced pancaked austenite, and a fine mixture of intragranular ferrite+pearlite. In both cases, the TMP forging schedules produced significant increases in hardness compared with the conventionally forged material.