Analysis on Big Fluctuation in Elevated Temperature Ductility of Solution S31042 Steel
WANG Jing-zhong1，2，LIU Zheng-dong1,CHENG Shi-chang1，BAO Han-sheng1
1. Institute for Structural Materials, Central Iron and Steel Research Institute, Beijing 100081, China 2. School of Metallurgy and Engineering, Xi’an University of Architecture and Technology, Xi’an 710055, Shaanxi, China
Abstract：In order to analyze the reasons which cause big fluctuation in elevated temperature ductility of S31042 steel, the fracture morphologies, surface and microstructure of specimens were observed by stereomicroscope, metallographic microscope, scanning electron microscope(SEM), transmission electron microscope. Extracts powder from specimens at corresponding condition were analyzed by X-ray diffraction. Phase diagram of S31042 steel were calculated using Thermo-Calc software. The results show that the big particle of NbCrN in cluster distributing on grain boundaries and in grains is the reason which leads to low short-term elevated temperature (at 700℃) tensile ductility (elongation only be 28%) of S31042 steel and serious surface checking. However, the specimen of S31042 steel with fine Nb-precipitation particles distributing dispersedly in grain have relatively high short-term elevated temperature (at 700℃) tensile ductility (elongation reaching 50%) and no surface checking on the surface of fracture specimens. The major reason which causes fluctuation in elevated temperature ductility of S31042 steel is morphologies of Nb-bearing phase. Therefore, improving the morphologies of niobium precipitation particles is beneficial to enhance the short-term elevated temperature tensile ductility for solution treatment S31042 steel.
王敬忠，，刘正东，程世长，包汉生. 固溶态S31042钢高温塑性波动大的原因分析[J]. 钢铁, 2012, 47(1): 60-64.
WANG Jing-zhong1，2，LIU Zheng-dong1,CHENG Shi-chang1，BAO Han-sheng1. Analysis on Big Fluctuation in Elevated Temperature Ductility of Solution S31042 Steel. Iron and Steel, 2012, 47(1): 60-64.
2012, Vol. 47 
