Dry sliding friction and wear test of Nb containing low carbon microalloyed steel was carried out at room temperature,and the effect of Nb on the wear behavior of the steel,as welll as the mechanism was studied.Scanni...Dry sliding friction and wear test of Nb containing low carbon microalloyed steel was carried out at room temperature,and the effect of Nb on the wear behavior of the steel,as welll as the mechanism was studied.Scanning electron microscopy(SEM) and energy dispersive spectrometry(EDS) were employed to analyze the morphology and composition of the worn surface,and the structure evolution of the plastic deformation layer.The carbide content and type in the steel were analyzed by the electrolytic extraction device and X-ray diffraction(XRD).The experimental results demonstrate that the addition of 0.2% Nb can refine the grain and generate Nb C to improve the wear resistance of the steel.By enhancing the load and speed of wear experiment,the wear mechanism of the test steel with 0.2% Nb changes from slight oxidation wear to severe adhesion wear and oxidation wear.Compared with the load,the increase in the rotation speed exerts a greater influence on the wear of the test steel.展开更多
Based on their hot ductilities, Nb, V and Ti microalloying steels can be classified into two groups. The first group includes steels with lower carbon content (≤0.10%). Ductilities of steels of this group recover and...Based on their hot ductilities, Nb, V and Ti microalloying steels can be classified into two groups. The first group includes steels with lower carbon content (≤0.10%). Ductilities of steels of this group recover and rise with decreasing temperature when temperature lowers to below 825℃. Another group includes steels which contain more carbon (>0.12%) or contain more Nb and V. The low ductility temperature Region Ⅲ for steels of mis group extends to temperature as low as 725℃. The occurrence of the transverse corner cracks of the Nb, V and Ti microalloying steel CC slabs has be considerably decreased by stabilizing casting speed, increasing mold steel level automatic control ratio,enhancing caster segment radial alignment and adopting proper secondary cooling patterns to make slab corner temperature at straightening out off the low ductility temperature region.展开更多
文摘Dry sliding friction and wear test of Nb containing low carbon microalloyed steel was carried out at room temperature,and the effect of Nb on the wear behavior of the steel,as welll as the mechanism was studied.Scanning electron microscopy(SEM) and energy dispersive spectrometry(EDS) were employed to analyze the morphology and composition of the worn surface,and the structure evolution of the plastic deformation layer.The carbide content and type in the steel were analyzed by the electrolytic extraction device and X-ray diffraction(XRD).The experimental results demonstrate that the addition of 0.2% Nb can refine the grain and generate Nb C to improve the wear resistance of the steel.By enhancing the load and speed of wear experiment,the wear mechanism of the test steel with 0.2% Nb changes from slight oxidation wear to severe adhesion wear and oxidation wear.Compared with the load,the increase in the rotation speed exerts a greater influence on the wear of the test steel.
文摘Based on their hot ductilities, Nb, V and Ti microalloying steels can be classified into two groups. The first group includes steels with lower carbon content (≤0.10%). Ductilities of steels of this group recover and rise with decreasing temperature when temperature lowers to below 825℃. Another group includes steels which contain more carbon (>0.12%) or contain more Nb and V. The low ductility temperature Region Ⅲ for steels of mis group extends to temperature as low as 725℃. The occurrence of the transverse corner cracks of the Nb, V and Ti microalloying steel CC slabs has be considerably decreased by stabilizing casting speed, increasing mold steel level automatic control ratio,enhancing caster segment radial alignment and adopting proper secondary cooling patterns to make slab corner temperature at straightening out off the low ductility temperature region.
基金the financial supports from the National Natural Science Foundation of China(No.51505323)State Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology,China(No.AWJ-17M-04).