Properties and uses of 42CrMo4 steel

42CrMo4 steel is the main material for manufacturing wind power fasteners, and its mechanical properties can be significantly improved by conditioning treatment. At present, the commonly used tempering heating equipment for wind power fasteners includes trolley furnace, mesh belt furnace and induction heating device. Net belt furnace productivity is high, product quality is stable, easy to realize automatic operation.

The hardness, grain size, yield strength, elongation after fracture, shrinkage of section and impact toughness of 42CrMo4 steel bar are similar after quenching by induction heating and tempering by mesh furnace.

Through numerical simulation, the induction hardening heating rate of 42CrMo4 steel bar is above 20 ℃/s at first, and decreases to about 2 ℃/s when the bar reaches austenitizing temperature above.

By controlling the tempering heating rate, temperature and holding time, the precipitation of carbide in large Angle grain boundary and small Angle grain boundary can be controlled to further improve the performance of 42CrMo4 steel. But because the induction heating time is very short, it is difficult to control.