Effect of controlled rolling/controlled cooling parameters on microstructure and mechanical properties of the novel pipeline steel  

作　　者：Min Jiang Li-Na Chen Jin He Guang-Yao Chen Chong-He Li Xiong-Gang Lu 

机构地区：[1]Shanghai Key Laboratory of Modern Metallurgy & Materials Processing,Shanghai University [2]Baoshan Iron & Steel Co.,Ltd. [3]Shanghai Special Casting Engineering Technology Research Center

出　　处：《Advances in Manufacturing》2014年第3期265-274,共10页先进制造进展（英文版）

基　　金：the National Nature Science Foundation of China(Grant Nos.51374142,51225401);the Science and Technology Fund of Scientific Committee of Shanghai(Grant Nos.11520500100,11DZ2283400);the Open Project of the State Key Laboratory of New Ferrous Metallurgy Technology(Grant No. KF12-05)

摘　　要：The study of controlled rolling/controlled cooling process parameters which affect the microstructure and mechanical properties of a novel pipeline steel has been optimized by the orthogonal experiment with four factors and three levels in this paper. However, the parameters of thermo-mechanical control process （TMCP） optimized by the Gleeble-3500 hot simulator could not satisfy performance requirements of the X100 pipeline steel. In order to improve the performance of this steel, the influence of finish cooling temperature （FCT） on the microstructure and property is studied in detail. It is found that, as this steel is thermo-mechanically treated by this set of parameters （the start heating temperature, finish rolling temperature （FRT）, FCT and cooling rate of 1,180 ℃, 810 ℃, 350 ℃ and 35 ℃/s, respectively）, the micro- structures are mainly composed of granular bainite （GB） and acicular ferrite （AF）. The effective grain sizes are below 20 μm; the steel reaches the optimal balance between the strength and the toughness; the yield strength is 695 MPa; the tensile strength is 768 MPa; the elongation is 16.6 %; the impact energy is 262 J at room temperature. All indexes could meet the requirements of X100 pipeline steel.The study of controlled rolling/controlled cooling process parameters which affect the microstructure and mechanical properties of a novel pipeline steel has been optimized by the orthogonal experiment with four factors and three levels in this paper. However, the parameters of thermo-mechanical control process （TMCP） optimized by the Gleeble-3500 hot simulator could not satisfy performance requirements of the X100 pipeline steel. In order to improve the performance of this steel, the influence of finish cooling temperature （FCT） on the microstructure and property is studied in detail. It is found that, as this steel is thermo-mechanically treated by this set of parameters （the start heating temperature, finish rolling temperature （FRT）, FCT and cooling rate of 1,180 ℃, 810 ℃, 350 ℃ and 35 ℃/s, respectively）, the micro- structures are mainly composed of granular bainite （GB） and acicular ferrite （AF）. The effective grain sizes are below 20 μm; the steel reaches the optimal balance between the strength and the toughness; the yield strength is 695 MPa; the tensile strength is 768 MPa; the elongation is 16.6 %; the impact energy is 262 J at room temperature. All indexes could meet the requirements of X100 pipeline steel.

关 键 词：Controlled rolling/controlled cooling Finishcooling temperature （FCT） Microstructure ~ Mechanicalproperties X100 pipeline steel 

分 类 号：TG335[金属学及工艺—金属压力加工] TG142.1[一般工业技术—材料科学与工程]