The Ti(C,N)precipitation and texture evolution in ultra-low carbon Ti-bearing enamel steel were studied to discover their correlation.Two different cooling paths of simulative coiling were adopted to gain different ...The Ti(C,N)precipitation and texture evolution in ultra-low carbon Ti-bearing enamel steel were studied to discover their correlation.Two different cooling paths of simulative coiling were adopted to gain different morphologies of Ti(C,N)precipitate in hot strips.It is found that the Ti(C,N)precipitate in hot strip using Path 2(put into asbestos box and air cooled)are finer and much more in quantity than that in hot strip using Path 1(held at 730℃ for 30min and furnace cooled).The morphology of Ti(C,N)precipitate in hot strip has great effect on recrystallization texture in the subsequent cold-rolled annealed sheet.γ-fiber texture of strong recrystallization is gained in coldrolled and annealed sheet came from Path 1.On the contrary,in the one came from Path 2,theγ-fiber texture is weak.This may be due to the pinning force of numerous fine Ti(C,N)precipitate which retard the growth of preferential nucleated{111}orientated grains.Annealed steel sheets in the test came from both paths have excellent fishscale resistance.展开更多
The nanometer-size carbides formed in ferrite matrix of Nb-Ti microalloyed steel at different finishing cooling temperatures and holding time have been investigated. The characteristics of nanometer-size carbides in f...The nanometer-size carbides formed in ferrite matrix of Nb-Ti microalloyed steel at different finishing cooling temperatures and holding time have been investigated. The characteristics of nanometer-size carbides in ferrite were observed by transmission electron microscopy, and mechanical properties of ferrite were detected by a nano-hardness tester. The results showed that interphase precipitation and diffusion precipitation were observed at different finishing cooling temperatures, and the interphase precipitation was planar and curved. Sheet spacing of inter-phase precipitation increased with the increase of finishing cooling temperature and changed a little when holding for 50--1000 s. Interphase precipitation shows higher nano-hardness at 640℃ compared with diffusion precipitation at 600℃, and the contribution of interphase precipitation to the mechanical properties of ferrite was larger than that of diffusion precipitation.展开更多
基金Sponsored by National Natural Science Foundation of China(50527402)National Basic Research Program(973Program)of China(2011CB606306-2)
文摘The Ti(C,N)precipitation and texture evolution in ultra-low carbon Ti-bearing enamel steel were studied to discover their correlation.Two different cooling paths of simulative coiling were adopted to gain different morphologies of Ti(C,N)precipitate in hot strips.It is found that the Ti(C,N)precipitate in hot strip using Path 2(put into asbestos box and air cooled)are finer and much more in quantity than that in hot strip using Path 1(held at 730℃ for 30min and furnace cooled).The morphology of Ti(C,N)precipitate in hot strip has great effect on recrystallization texture in the subsequent cold-rolled annealed sheet.γ-fiber texture of strong recrystallization is gained in coldrolled and annealed sheet came from Path 1.On the contrary,in the one came from Path 2,theγ-fiber texture is weak.This may be due to the pinning force of numerous fine Ti(C,N)precipitate which retard the growth of preferential nucleated{111}orientated grains.Annealed steel sheets in the test came from both paths have excellent fishscale resistance.
基金Item Sponsored by National Natural Science Foundation of China(51104046)Fundamental Research Funds for Central Universities of China(N120407001,N120807001)
文摘The nanometer-size carbides formed in ferrite matrix of Nb-Ti microalloyed steel at different finishing cooling temperatures and holding time have been investigated. The characteristics of nanometer-size carbides in ferrite were observed by transmission electron microscopy, and mechanical properties of ferrite were detected by a nano-hardness tester. The results showed that interphase precipitation and diffusion precipitation were observed at different finishing cooling temperatures, and the interphase precipitation was planar and curved. Sheet spacing of inter-phase precipitation increased with the increase of finishing cooling temperature and changed a little when holding for 50--1000 s. Interphase precipitation shows higher nano-hardness at 640℃ compared with diffusion precipitation at 600℃, and the contribution of interphase precipitation to the mechanical properties of ferrite was larger than that of diffusion precipitation.