TY - JOUR
T1 - Influence of aging and thermomechanical treatments on the mechanical properties of a nanocluster-strengthened ferritic steel
AU - Zhang, Z. W.
AU - Liu, C. T.
AU - Wen, Y. R.
AU - Hirata, A.
AU - Guo, S.
AU - Chen, G.
AU - Chen, M. W.
AU - Chin, Bryan A.
N1 - Funding Information:
This research was supported mainly by internal funding from Auburn University, Hong Kong City University, and together with the NJUST Research Funding (No. 2010GIPY031) and the National Natural Sciences Foundation of China (No. 50871054). Z.W.Z. benefitted from the Visiting Postdoctoral Research Program at the Neutron Scattering Science Division, Oak Ridge National Laboratory, Oak Ridge, TN.
PY - 2012/1
Y1 - 2012/1
N2 - This study investigated the effect of aging and thermomechanical treatments on the mechanical properties of a nanocluster-strengthened ferritic steel, Fe-1.5Mn-2.5Cu-4.0Ni-1.0Al (wt pct). The effect of thermomechanical treatments on the microhardness and tensile properties were measured at room temperature and correlated with microstructural features. Cu-rich precipitates were characterized by transmission electron microscopy and were found to coarsen slowly during long-time aging. The microhardness measurements indicate a typical precipitation hardening behavior during aging at 773 K (500 °C). Tensile tests showed that thermomechanical treatments can improve the mechanical strength and ductility of the nanocluster-strengthened ferritic steel significantly compared with those without the treatments. Fractography results indicated that the high yield strength resulted from precipitation hardening makes the steel more susceptible to grain-boundary decohesion, which can be suppressed by grain refinement. Atmosphere adsorption and diffusion along grain boundaries were found to intensify brittle intergranular fracture, and this embrittlement can be avoided by vacuum heat treatment.
AB - This study investigated the effect of aging and thermomechanical treatments on the mechanical properties of a nanocluster-strengthened ferritic steel, Fe-1.5Mn-2.5Cu-4.0Ni-1.0Al (wt pct). The effect of thermomechanical treatments on the microhardness and tensile properties were measured at room temperature and correlated with microstructural features. Cu-rich precipitates were characterized by transmission electron microscopy and were found to coarsen slowly during long-time aging. The microhardness measurements indicate a typical precipitation hardening behavior during aging at 773 K (500 °C). Tensile tests showed that thermomechanical treatments can improve the mechanical strength and ductility of the nanocluster-strengthened ferritic steel significantly compared with those without the treatments. Fractography results indicated that the high yield strength resulted from precipitation hardening makes the steel more susceptible to grain-boundary decohesion, which can be suppressed by grain refinement. Atmosphere adsorption and diffusion along grain boundaries were found to intensify brittle intergranular fracture, and this embrittlement can be avoided by vacuum heat treatment.
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U2 - 10.1007/s11661-011-0835-4
DO - 10.1007/s11661-011-0835-4
M3 - Article
AN - SCOPUS:84855768972
SN - 1073-5623
VL - 43
SP - 351
EP - 359
JO - Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
JF - Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
IS - 1
ER -