Effect of precipitation of (Ti,V)N and V(C,N) secondary phases on mechanical properties of V and N microalloyed 1Cr steels

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:738

Article

Zhang, Z. H.¹  Liu, Y.^2,3  Zhou, Y. N.^2,3  Dong, X. M.¹  Zhang, C. X.¹  Cao, G. H.^2,3  Schneider, R.⁴  Gerthsen, D.⁴ 

[1] Baoshan Iron & Steel Co Ltd, Baosteel Res Inst, Tube & Pipe Dept, Shanghai 201900, Peoples R China

[2] Shanghai Univ, State Key Lab Adv Special Steel, 149 Yanchang Rd, Shanghai 200072, Peoples R China

[3] Shanghai Univ, Sch Mat Sci & Engn, 149 Yanchang Rd, Shanghai 200072, Peoples R China

[4] Karlsruher Inst Technol, Lab Elektronenmikroskopie, D-76128 Karlsruhe, Germany

关键词: Steels;    Microstructure;    Mechanical properties;    Precipitation strengthening;    Electron microscopy;   

DOI  :  10.1016/j.msea.2018.09.102

来源: Elsevier

【 摘 要 】

The influence of (Ti,V)N- and V(C,N)-type precipitates on the mechanical properties was studied using transmission electron microscopy, energy-filtered transmission electron microscopy, and electron energy-loss spectroscopy for four medium carbon 1Cr steels containing various amounts of vanadium and nitrogen in the hotrolled and normalized states. (Ti,V)N-type nanoparticles were found only in the proeutectoid ferrite, while V (C,N)-type nanometer precipitates were distributed in ferrite and further promoted the transformation of pearlite. Addition of vanadium and nitrogen refined the size of the precipitates and increased the volume fraction of pearlite, leading to increased strength. A linear arrangement of (Ti,V)N nitrides and V(C,N) carbonitrides was observed after normalization and resulted in an increase of elongation-to-failure from 16% to 22% at the expense of a 103 MPa decrease in the strength. The precipitation mechanism of Ti-rich nitrides and V-rich carbonitrides and their effects on the mechanical properties of the ferrite-pearlite 1Cr steels were discussed.

【 授权许可】

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