$ D.L*
,
D.N.He
,
X.J.Bao
,
Y. Q.Zhang
,
X. Y.Ruan
,
J.L. Cheng and J. Y. Jiang 1) National Die & Mold CAD Engineering Research Center
,
Shanghai Jiaotong University
,
Shanghai 200030
,
China 2) Shanghai Volkswagen Automotive Company Limited
,
Shanghai 201805
,
China
金属学报(英文版)
With the combination of a new theoretical formula, physical simulation experiments, the technology of artificial neural network and database, an intelligent system for the prediction of sheet metal drawing capability is constructed for the first time. A modified criterion for sheet metal drawing capability is proposed in this paper, namely, the Technological Limiting Drawing Ratio, TLDR = f(R, n, s, t, F, μ,r_d,r_p…). Based on the studies of other scholars, a new formula is derived to predict the TLDR in this paper. Then a series of orthogonal physical simulation experiments are designed to investigate the effect of technological parameters on the TLDR, and the results are analyzed in the paper. Then the predicting system is constructed with the combination of the theoretical formula, orthogonal experiments, the technology of artifocial neural network and database. The predicted results show good agreements with experimental data, so it can be used to avoid the blindness in the selection of sheet metal before stamping. The system operates under the Windows operating system, and it supports the mechanism of Client/Server as well as Intranet, so the system has high engineering value.
关键词:
TLDR
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null
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null
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null
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null
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null
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null
Z.L. Ding
,
Y.C. Fan
,
H.B. Qi
,
D.L. Ren
,
J.B. Guo and Z.Q. Jiang Shijiazhuang Railway Institute
,
Shijiazhuang 050043
,
China
金属学报(英文版)
The SiC_p/Al-alloy composite front broke rotors designed for SHANGHAI SANTANA cars were prepared by semi-solid stirring+liquid for ping process. The properties of the composite rotors were examined. The composite brake rotors were subjected to dynamometer tests on a SCHENCK broke testing system, referring to TLll0 standard of VOLKSWAGEN Company. The friction coefficient and thermal response during fade testing and the wear performance of the composite rotors were studied as the function of various parameters, such as braking pressures, initial speeds, initial temperatures, torque and decelerations, and compared with that of conventional cast iron rotors. The results showed that the properties of SiC_p,/Al-alloy composite rotors can achieve the requirements of commercial cast iron rotor.s. The results also suggested that the friction coefficients of composite rotors under different broking conditions are within the deviation band specified by the TLll0 standard, and the temperature rise of the composite rotors at the cud of each fade stop is lower than that of the cast iron rotors. The wear resistance of composite rotors was higher than that of cast iron rotors. The friction and wear mechanism are analyzed.
关键词:
SiC_p/Al-alloy composite
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null
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null
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null
L. P. Xu
,
M. H. Xu
,
L. Li
,
Y.A. Min
,
X.Z Xuand R.H .Liu (Department of Materials Science and Engineering
,
Shanghai University
,
Shanghai 200072
,
China) (Shanghai No.5 Iron and Steel Factory
,
Shanghai 200940
,
China)
金属学报(英文版)
The composition of a bearing steel was designed for limited hardenability by use of Grossmann's method. A medium frequency induction Process was applied to heat bearings to ensure penetrant heating and suitable solving of carbon and other elements in the matrix. The hardened depth measured from the end quenching test samples and actual bearings matches well with the designed one.
关键词:
: bearing steel
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null
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null
Journal of Physics-Condensed Matter
The vibrational densities of states for the diffusion-limited aggregate with varying elastic force consstants are calculated by the recursion method of Haydock, Heine and Kelly. It is found that the spectrum with central forces is very different from that with isotropic forces which is characterized by a power-law behaviour in the fraction frequency regime. An interesting crossover is also observed when the ratio of the central to the non-central force constants of the Born model varies from alpha/beta = 1 to alpha/beta = inifity.
关键词:
local atomic environment;tight-binding bands;elastic properties;percolation;systems;exponent
Physical Review B
The vibrational densities of states for a series of field-biased diffusion-limited aggregation clusters with varying fractal dimensions in two Euclidean dimensions are computed numerically by the continued-fraction recursion method. It is confirmed that the density of states is characterized by a power-law behavior in the fracton-frequency regime. The fraction dimensionalities are found to favor the Aharony-Stauffer conjecture in the present case. Numerical results also show that the fraction mode is strongly localized in the diffusion-limited aggregation systems.
关键词:
effective-medium approximation;percolation clusters;phonon;localization;density;network;glasses;states;growth
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
SUN Wenqiang
,
CAI Jiuju
,
MAO Hujun
,
GUAN Duojiao
钢铁研究学报(英文版)
As the largest energy consuming manufacturing sector and one of the most important sources of carbon dioxide (CO2) emissions, the China′s iron and steel industry has paid attention to the study of changing trend and influencing factors of CO2 emissions from energy use. The logarithmic mean Divisia index (LMDI) technique is used to decompose total change in CO2 emissions into four factors: emission factor effect, energy structure effect, energy consumption effect, and steel production effect. The results show that the steel production effect is the major factor which is responsible for the rise in CO2 emissions; whereas the energy consumption effect contributes most to the reduction in CO2 emissions. And the emission factor effect makes a weak negative contribution to the increase of CO2 emissions. To find out the detailed relationship between change in energy consumption or steel production and change in CO2 emissions, the correlation equations are also proposed.
关键词:
CO2 emissions
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energy use
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LMDI technique
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steel production
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energy consumption
XIAN Aiping LI Peiji CHEN Wenxiu WANG Yikang Institute of Metal Research
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Academia Sinica
,
Shenyang
,
ChinaCHEN Renvi MEI Dongsheng Panzhihua Institute of Iron and Steel Research
,
Ministry of Metallurgical Industry
,
Panzhihua
,
China associate professor
,
Institute of Metal Research
,
Academia Sinica
,
Shenyang 110015
,
China
金属学报(英文版)
The determination of dffusible hydrogen in U71Mn heavy rail steel,and hydrogen diffusivity as well as the hydrogen distribution in the cross section of blooms with stack cooling were stu- died.The results showed that,most of the hydrogen in blooms of heavv rail steel is diffusible, the hydrogen diffusivity in U71Mn rail steel blooms at room temperature is(0.85—1.02)× 10~(-6)cm~2/s,after stack cooling,the hydrogen content in bloom will decrease greatly which is helpful to form the flake-free phenomenon in the heavy rail produced by Panzhihua Iron and Steel Company.
关键词:
rail steel
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null
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null
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null
