TY - JOUR
T1 - Effects of Boron on the Microstructure, Ductility-dip-cracking, and Tensile Properties for NiCrFe-7 Weld Metal
AU - Mo, Wenlin
AU - Hu, Xiaobing
AU - Lu, Shanping
AU - Li, Dianzhong
AU - Li, Yiyi
N1 - Funding Information:
The authors are grateful for financial support by the National Natural Science Foundation of China (No. 51474203 ) and Key Research Program of the Chinese Academy of Sciences (No. KGZD-EW-XXX-2 ). The authors also wish to recognize the assistance provided by China First Heavy Machinery Co. Ltd. in the welding process.
Publisher Copyright:
© 2015.
PY - 2015/12/1
Y1 - 2015/12/1
N2 - The distribution of boron and the microstructure of grain boundary (GB) precipitates (M23(C, B)6 and M2B) have been analyzed with their effects on the susceptibility of ductility-dip-cracking (DDC) and tensile properties for NiCrFe-7 weld metal, using optical microscopy (OM), secondary ion mass spectroscopy (SIMS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results show that boron segregates at GBs in NiCrFe-7 weld metal during the welding process. The segregation of boron at GBs promotes the formation of continuous M23(C, B)6 carbide chains and M2B borides along GBs. The addition of boron aggravates GB embrittlement and causes more DDC in the weld metal, by its segregation at GBs presenting as an impurity, and promoting the formation of larger and continuous M23(C, B)6 carbides, and M2B borides along GBs. DDC in the weld metal deteriorates the ductility and tensile strength of the weld metal simultaneously.
AB - The distribution of boron and the microstructure of grain boundary (GB) precipitates (M23(C, B)6 and M2B) have been analyzed with their effects on the susceptibility of ductility-dip-cracking (DDC) and tensile properties for NiCrFe-7 weld metal, using optical microscopy (OM), secondary ion mass spectroscopy (SIMS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results show that boron segregates at GBs in NiCrFe-7 weld metal during the welding process. The segregation of boron at GBs promotes the formation of continuous M23(C, B)6 carbide chains and M2B borides along GBs. The addition of boron aggravates GB embrittlement and causes more DDC in the weld metal, by its segregation at GBs presenting as an impurity, and promoting the formation of larger and continuous M23(C, B)6 carbides, and M2B borides along GBs. DDC in the weld metal deteriorates the ductility and tensile strength of the weld metal simultaneously.
KW - Boron
KW - Ductility-dip-cracking
KW - MB
KW - MC
KW - Tensile properties
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U2 - 10.1016/j.jmst.2015.08.001
DO - 10.1016/j.jmst.2015.08.001
M3 - Article
AN - SCOPUS:84940726906
SN - 1005-0302
VL - 31
SP - 1258
EP - 1267
JO - Journal of Materials Science and Technology
JF - Journal of Materials Science and Technology
IS - 12
ER -