Li C.,Guizhou University |
Li C.,Guizhou Key Laboratory for Mechanical Behavior and Microstructure of Materials |
Yao Z.,Guizhou University |
Liang Z.,Guizhou University
Advanced Materials Research | Year: 2011
Continuous casting process parameters such as casting speed, superheat, secondary cooling water flow rate have greatly affections to central defects in SWRH82B billet. These parameters were investigated by the methods of chemical content analysis and etch test for macrostructure in some steel plant of china. The results shows that the central defect of SWRH82B billet can be improved when the superheat is controlled at the range of 15∼25°C, casting speed is 1.80m·min-1 and secondary cooling water flow rate is 0.72 L·kg-1. © (2011) Trans Tech Publications.
Ren Y.-H.,Guizhou University |
Zhao F.,Guizhou University |
Zhao F.,Guizhou Key Laboratory for Mechanical Behavior and Microstructure of Materials |
Yan Y.,Guizhou University
Cailiao Rechuli Xuebao/Transactions of Materials and Heat Treatment | Year: 2013
Influence of heating temperature and holding time on the grain growth of 18Ni(1700 MPa) maraging steel were studied. The grain growth model of 18Ni maraging steel has been established by regression with experiment data and the applicability of the model is verified. The results show that grain evolution experiences three stages when holding at temperature of 930-1070°C inverted austenitic recrystallization incubation period, inverted austenitic recrystallization process and recrystallized grain re-growing. The grain is refined obviously in recrystallization process. The refined grains will grow up again at a high speed after the tens of seconds of the recrystallization of reverted austenite, the higher temperature, the higher the grains growth rate, and the grains growing rate is reduced with the increase of holding time. The predictive and measured grain size coincides rather well.
Huang C.,Guizhou University |
Huang C.,Guizhou Key Laboratory for Mechanical Behavior and Microstructure of Materials |
Liang Y.,Guizhou University |
Liang Y.,Guizhou Key Laboratory for Mechanical Behavior and Microstructure of Materials |
And 4 more authors.
Jinshu Rechuli/Heat Treatment of Metals | Year: 2013
Microstructure and fatigue properties of 211Z.X heat-resisting high strength and toughness aluminum alloy under T6 heat treatment condition were studied. The fatigue fracture surface was analyzed by scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). The results show that the fatigue limit of the alloy is 154.25 MPa and its range from 147.13 MPa to 140 MPa when the survival rate P is from 50% to 99.9%. Fatigue cracks are often found to initiate from Ce-rich rare earth particles and Fe-rich intermetallic particles, which are located near the subsurface of the specimens. It also shows that fatigue cracks propagate radially as a transcrystalline and intercrystalline mixed propagation mechanism.
Zeng H.,Guizhou University |
Zeng H.,Guizhou Key Laboratory for Mechanical Behavior and Microstructure of Materials |
Xiang S.,Guizhou University |
Xiang S.,Guizhou Key Laboratory for Mechanical Behavior and Microstructure of Materials |
And 2 more authors.
Corrosion Science and Protection Technology | Year: 2014
Electrochemical performance was studied for 904L stainless steel after solution treatment at different temperatures in concentrated sulfuric acid by means of measurements potentiodynamic polarization curve and cycle polarization curve. The results show that the solution temperature has little effect on cathodic process, but varies the anodic polarization curve greatly. Whilst 904L stainless steel shows the best corrosion resistance after solution treatment at 1120 °C for 0.5 h.
Zhu J.,Guizhou University |
Zhu J.,Guizhou Key Laboratory for Mechanical Behavior and Microstructure of Materials |
Yang C.,Guiyang University |
Jiang Y.,Guizhou Key Laboratory for Mechanical Behavior and Microstructure of Materials |
And 3 more authors.
Jinshu Rechuli/Heat Treatment of Metals | Year: 2016
Under the same quenching process (910 ℃×30 min), influence of different tempering temperature (400-520 ℃) on microstructure and mechanical properties of 60Si2CrVAT spring steel was investigated. The results show that quenched at 910 ℃ for 30 min and tempered at 430 ℃ for 60 min, the strength and toughness of the steel is best. With tempering temperature increased from 400 ℃ to 520 ℃, the strength and hardness of the steel decrease, and the elongation and contraction of cross sectional area first increase and then decrease. When tempering temperature is 430 ℃, the strain hardening exponent reaches the maximum value 0.086. The microstructures of spring steel tempered between 400 ℃ and 520 ℃ are tempering troostite, and needle-shaped ferrit tends to grow up and the residual austenite is decomposed with the temperature increasing. © 2016, Chinese Mechanical Engineering Society of Heat Treatment. All right reserved.