Microstructure Evolution at Different Cooling Rates of Low Carbon Microalloyed Steels  

作　　者：Elena Brandaleze Matias Ramirez Martina Avalos 

机构地区：[1]Metallurgy Department and Deytema Centre, Universidad Tecnologica Nacional, Facultad Regional San Nicolas, Colon 332,2900 San Nicolas, Argentina [2]IFIR-Conicet, Universidad Nacional de Rosario, Ocampo y Esmeralda, Ocampo 210 bis, 2000 Rosario, Argentina

出　　处：《Journal of Chemistry and Chemical Engineering》2017年第1期22-29,共8页化学与化工（英文版）

摘　　要：In low carbon microalloyed steels （C 〈 0.1%）, the content of V, Nb and Ti affects the phases transformation kinetic during cooling in the rolling process. The final microstructure determines the required mechanical properties such as high formability, high toughness and adequate strength. For this reason it is relevant to identify and determine the volume fraction of the ferrite, bainite and martensite present in the structure. The microalloying elements： V, Nb and Ti promote carbides precipitation during cooling. The precipitates control the grain size refinement during hot rolling process and the mechanical properties of the steel. In this sense it is necessary to increase the knowledge on the microstructure evolution at different cooling rates. In this paper, the results obtained on two low carbon microalloyed steels （with C contents between 0.11%-0.06%） are reported. An integrated methodology including dilatometry in combination with microscopy techniques was applied. By EBSD （Electron Backscatter Diffraction） technique and microhardness measurements, the structural study was completed. Through a thermodynamic simulation using Fact Sage the type of precipitates in the studied steels structure at the temperature range between 950 ℃ and 450 ℃, were predicted. The information on the evolution of the steel structure at rolling process conditions is relevant to consider changes in processing conditions.

关 键 词：Low carbon steels dilatometry cooling curves phases transformation precipitates. 

分 类 号：TG142.33[一般工业技术—材料科学与工程] TG146.21[金属学及工艺—金属材料]