ժҪ The ultra-fast cooling technology of large-section bars GCr15 bearing steel was researched connected with industry practice, the microstructure in different cooling patters were researched by optical microscopy��transmission electron microscopy and energy spectrometer, it was concluded that: the large-section bars of GCr15 bearing steel passed the zone of secondary carbide precipitation quickly through the ultra-fast cooling technology(UFC) the instantaneous cooling rate of which was about 200��/s, the finishing cooling temperature was higher than Ms, the lamellar spacing of pearlite was thinner and thinner and the micro-hardness was bigger and bigger along with the reduction of re-reddening temperature��the precipitation of network carbide was restrained when re-reddening temperature was 690��, and fine laminated pearlite was obtained through transformation of pseudopearlition which induced the reduction of the diamond of pearlite grain and refinement of the lamellar spacing of pearlite, ideal microstructures promoting spheroidizing annealing were obtained.
Abstract��The ultra-fast cooling technology of large-section bars GCr15 bearing steel was researched connected with industry practice, the microstructure in different cooling patters were researched by optical microscopy��transmission electron microscopy and energy spectrometer, it was concluded that: the large-section bars of GCr15 bearing steel passed the zone of secondary carbide precipitation quickly through the ultra-fast cooling technology(UFC) the instantaneous cooling rate of which was about 200��/s, the finishing cooling temperature was higher than Ms, the lamellar spacing of pearlite was thinner and thinner and the micro-hardness was bigger and bigger along with the reduction of re-reddening temperature��the precipitation of network carbide was restrained when re-reddening temperature was 690��, and fine laminated pearlite was obtained through transformation of pseudopearlition which induced the reduction of the diamond of pearlite grain and refinement of the lamellar spacing of pearlite, ideal microstructures promoting spheroidizing annealing were obtained.
SUN Yan-Kun. Effect of Ultra-fast cooling on the microstructure of large-section bars of bearing steel[J]. �й������ڿ���, 2009, 16(5): 61-61.
SUN Yan-Kun. Effect of Ultra-fast cooling on the microstructure of large-section bars of bearing steel. Chinese Journal of Iron and Steel, 2009, 16(5): 61-61.