Miaoquan LI
,
Shankun XUE
,
Aiming XIONG
,
Shenghui CHEN
材料科学技术（英文）
Hot compression was conducted at a Thermecmaster-Z simulator, at deformation temperatures of 800~1040℃, with strain rates of 0.001~50 s-1 and height reduction of 50%. Grain size of the prior α phase was measured with a Leica LABOR-LUX12MFS/ST microscope to which QUANTIMET 500 software for image analysis for quantitative metallography was linked. According to the present experimental data, a constitutive relationship for a TC6 alloy and a model for grain size of the prior α phase were established based on the Arrhenius' equation and the Yada's equation, respectively. By finite element (FE) simulation, deformation distribution was determined for isothermal forging of a TC6 aerofoil blade at temperatures of 860~940℃ and hammer velocities of 9~3000.0 mm/min. Meanwhile, the grain size of the prior α phase is simulated during isothermal forging of the TC6 aerofoil blade, by combining FE outputs with the present grain size model. The present results illustrate the grain size and its distribution in the prior α phase during the isothermal forging of the TC6 aerofoil blade. The simulated results show that the height reduction, deformation temperature, and hammer velocity have significant effects on distribution of the equivalent strain and the grain size of the prior α phase.
关键词:
Titanium alloy
,
null
,
null
,
null
,
null
稀土学报(英文版)
A dense and conductive LaCrO(3) coating was prepared on type 316 stainless steel (316 SS), aiming at exploring its potential applications in SOFC and in other high temperature environments. Powder of LaCrO(3) with perovskite structure was synthesized by sol-gel method. LaCrO(3) coating on 316 SS substrate was obtained by slurry coating technique. The microstructure of the coating on 316 SS after sintering in air at 800 and 900 degrees C for 200 h was characterized. The effect of LaCrO(3) coating on oxidation resistance of the steel in air was also investigated. The results showed that the coating was adhesive to the substrate and improved greatly the oxidation resistance of the alloy.
关键词:
SOFC;316 stainless steel;LaCrO(3) coating;oxidation;rare earths;oxide fuel-cells;sofc interconnect
S.J. Patel
金属学报(英文版)
Chinese utilities as well as those worldwide are facing increased demand for additional electricity, reduced plant emissions and greater efficiency. To meet this challenge will require increasing boiler temperature, pressure and coal ash corrosion resistance of the materials of boiler construction of future coal-fired boilers. A new nickel-based tube alloy, INCONELR alloy 740, is described aiming at meeting this challenge. Emphasis will be on describing the alloy's mechanical properties, coal-ash and steam corrosion resistance. Microstructural stability as a function of temperature and time is addressed as well as some of the early methodology employed to arrive at the current chemical composition.
关键词:
ultrasupercritical
,
null
,
null
Zang Xin-Liang LI Xue-Tong
钢铁研究学报(英文版)
Using 3D rigid-plastic finite element method (FEM), a numerical simulation model for the non-steady state vertical- horizontal rolling process in roughing trains has been built, and is validated by comparison between simulated and experimental values of width and shape of the stock ends. Aiming to certain 2050 roughing process technologies, short shape control (SSC) of the stock ends was investigated using the model. Based on the simulated results, a new SSC model was developed. Moreover, it can be seen that it is effective for the new SSC model to improve shape of the stock ends from the analyzed results.
关键词:
hot rolling;FEM;Simulation;edging;shape control
KEIZO HASHIMOTO(Advanced Technologies Research Laboratories Nippon Steel Corp.1618 Ida Nakahara-ku Kawasaki 211 JAPAN)
金属学报(英文版)
Gamma titanium aluminide (γ-TiAl)intermetallic compounds are spotlighted as lightweight heat-resistant materials, and have been investigated extensively to aiming commercial use.Fundamental approaches in which phase diagrams of Ti -Al -Cr and TiAl -Nb have been studied based on the experimental data and calculations , have been performed in the national project For industrial approach, ingot process and direct casting process have been developed to provide sheet form of TiAl. By these approaches, γ-TiAl base ,intermetallic compounds show a great possibility to apply in the variety of fields .However, a more detailed understanding of phase equilibrium in Ti-Al -X and the relationship between the mechanical properties and microstructure will be necessary
关键词:
: TITANIUM ALUMINIDE
,
null
,
null
,
null
,
null
Lin HU
,
Xiaodong HU
,
Peng GAO
,
Hongyang ZHAO
,
Dong-Ying Ju
材料科学技术（英文）
Based on the discussing of the mechanisms of grain refinement strengthening and deformation induced transformation, the characteristics of controlled rolling and controlled cooling for high-speed wire were analyzed. Aiming at the problems of wire mill in Anshan Iron & Steel Co., turbulent cooler and spray cooler on the Stelmor conveyor were developed. Super-steels had been developed for Q235 steel through unrecrystallized austenite region rolling. The constitution and properties of the wire on the coil overlap zone were also improved. This proved the possibility that super-steels can be developed in high-speed wire mill.
关键词:
Super-steel
,
null
,
null
,
null
International Journal of Vehicle Design
Taking the forming processes of half-shaft bushing, wayshaft, and starter socket as examples and aiming at the typical problems in extrusion of automotive parts, some defects such as folding, underfilling, and cracking were numerically simulated and predicted in this paper with rigid-plastic FEM, rigid-viscoplastic FEM, and thermo-mechanically coupled methods by means of DEFORM3D. The distribution laws for the stress, strain, velocity, and temperature in the forming processes were analysed. The reasons for the defect generation were discussed, and some optimum measures for these processes were put forward. The results agree well with the experiments. Several proposals for prediction and simulation of extrusion defects of these automotive parts are put forward. It was instructional to apply FEM to the quality control of the extrusion.
关键词:
extrusion defect;numerical simulation;half-shaft bushing;wayshaft;starter socket;folding;underfilling;crack
LIU Li-mei
,
WANG An-na
,
SHA Mo
,
ZHAO Feng-yun
钢铁研究学报(英文版)
Aiming at the limitations of rapid fault diagnosis of blast furnace, a novel strategy based on cost-conscious least squares support vector machine (LS-SVM) is proposed to solve this problem. Firstly, modified discrete particle swarm optimization is applied to optimize the feature selection and the LS-SVM parameters. Secondly, cost-conscious formula is presented for fitness function and it contains in detail training time, recognition accuracy and the feature selection. The CLS-SVM algorithm is presented to increase the performance of the LS-SVM classifier. The new method can select the best fault features in much shorter time and have fewer support vectors and better generalization performance in the application of fault diagnosis of the blast furnace. Thirdly, a gradual change binary tree is established for blast furnace faults diagnosis. It is a multi-class classification method based on center-of-gravity formula distance of cluster. A gradual change classification percentage is used to select sample randomly. The proposed new method raises the speed of diagnosis, optimizes the classification accuracy and has good generalization ability for fault diagnosis of the application of blast furnace.
关键词:
blast furnace
,
fault diagnosis
,
cost-conscious
,
LS-SVM
,
multi-class classification
TIAN Huixin
,
MAO Zhizhong
,
WANG Anna
钢铁研究学报(英文版)
Aiming at the limitations of traditional thermal model and intelligent model, a new hybrid model is established for soft sensing of the molten steel temperature in LF. Firstly, a thermal model based on energy conservation is described; and then, an improved intelligent model based on process data is presented by ensemble ELM (extreme learning machine) for predicting the molten steel temperature in LF. Secondly, the selfadaptive data fusion is proposed as a hybrid modeling method to combine the thermal model with the intelligent model. The new hybrid model could complement mutual advantage of two models by combination. It can overcome the shortcoming of parameters obtained online hardly in a thermal model and the disadvantage of lacking the analysis of ladle furnace metallurgical process in an intelligent model. The new hybrid model is applied to a 300 t LF in Baoshan Iron and Steel Co Ltd for predicting the molten steel temperature. The experiments demonstrate that the hybrid model has good generalization performance and high accuracy.
关键词:
ladle furnace;hybrid modeling;soft sensing;thermal model;data fusion
