The CCT curve of 100Cr6 bearing steel was measured by using thermal expansion instrument thermal simulation tester

metallographic microscope

field emission SEM

etc

it also studied the influence of thermal compression and controlled rolling and controlled cooling on network carbide precipitation behavior. The results show that: when the temperature of the secondary compression deformation decreases from 850 ℃ to700 ℃

the recrystallization refinement of austenite changes to non-recrystallization

and the secondary carbide gradually changed from closed network of grain boundary to semi-closed strip

short rod and then to chain along elongated austenite grain boundary

and the carbide was fine and dispersed in the range of 750-800 ℃.The Φ10 mm 100Cr6 wire adopts to control rolling and rapid cooling process from 910℃ to770 ℃. After hot rolling

spheroidal annealing and quenching and tempering

the carbide distribution uniformity is gradually improved

the austenite grain is refined from 8.0 grade to 10.0 grade

and the grain boundary carbide is trans- formed from closed mesh to discontinuous strip. The average thickness is reduced from 0.54 μm to 0.11 μm

and the network carbide level is reduced from33% of 3.0 grade to100% of 2.0 grade

which can shorten the spheroidizing annealing time and improve the fatigue life of bearings.