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Nie H.,Taiyuan University of Technology | Nie H.,Shanxi Coal Mining Administrators College | Liang W.,Taiyuan University of Technology | Yang F.,Taiyuan University of Technology | And 5 more authors.
JOM | Year: 2016

Three-layered 5052/AZ31/5052 clad sheets with maximum rolling reductions of 33% and 48% were prepared, using single-pass hot rolling followed by thermal annealing at 200°C for 1 h. The evolutions of microstructures and textures were analyzed. The experimental results show that the AZ31 layer exhibited a typical deformation microstructure with rolling-induced twins. The AZ31 layer with the 33% rolling reduction possessed a texture with the basal pole tilting about 35° away from normal direction to transverse direction and the majority of twins consists of {101 ¯ 1}–{101 ¯ 2} double twins and {101 ¯ 2} tensile twins. The AZ31 layer with the 48% rolling reduction possessed a typical basal texture because {101 ¯ 1} compression twins were activated by c-axis strain to compete with the tensile twins. No intermetallics were observed after annealing, and recrystallization occurred preferentially at the interface between AZ31 and 5052. The typical rolling texture of the 5052 layer disappeared, and the stable {001} 〈110〉 rotation cube component was dominant. The tensile test of the rolled three-layered 5052/AZ31/5052 clad sheets was performed. The tensile experimental results show that the annealed clad sheets with 33% rolling reduction and smaller degree of recrystallization have the largest elongation of 22.5% and larger ultimate tensile strength (UTS) than the annealed clad sheets with 48% rolling reduction. © 2016, The Minerals, Metals & Materials Society.

Hao J.-J.,Taiyuan University of Technology | Hao J.-J.,Shanxi Engineering Vocational College | Chen J.,Taiyuan University of Technology | Han P.-D.,Taiyuan University of Technology | And 2 more authors.
Steel Research International | Year: 2014

Solid phase decarburization of high carbon ferrochrome powders (HCFP) mixed with calcium carbonate powders (CCP) can be realized at a certain temperature in microwave heating field. The modified kinetic model is used and the results illustrate that, gas inner diffusion is the restrictive step of decarburization reaction, and apparent activation energy of the reaction is 72.80 kJ mol -1, which is much lower than that of carbon gasification reaction by conventional heating. Backscattered electron image analysis shows that the carbides in decarburized ferrochrome powders vary with temperature. With the temperature rising, the ratio of (Cr,Fe)7C3 decreases, (Cr,Fe)23C6 and chromium ferrite increases in the microwave field. Meanwhile, the thickness of oxide film around the decarburized ferrochrome powders enhances, which hinders gas inner diffusion. The optimum conditions of solid phase decarburization of HCFP by microwave heating are 1100°C and holding for 60 min. This paper deals with the kinetics of solid phase decarburization of HCFPs in microwave heating filed. Apparent activation energy of the solid phase decarburization reaction is calculated and restrictive step and the mechanism is also obtained. The optimum conditions of solid phase decarburization of HCFP by microwave heating are also concluded. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Wang C.-L.,Taiyuan University of Technology | Chen J.,Taiyuan University of Technology | Hao J.-J.,Taiyuan University of Technology | Hao J.-J.,Shanxi Engineering Vocational College | And 2 more authors.
Beijing Keji Daxue Xuebao/Journal of University of Science and Technology Beijing | Year: 2013

Solid-state decarburization kinetics of high-carbon ferrochrome powders was investigated by microwave heating. Calcium carbonate powders were used as a solid decarburizer. The high-carbon ferrochrome powders and calcium carbonate powders were mixed at the mole ratio between carbon in the high-carbon ferrochrome powders and CO2 decomposed from the calcium carbonate powders of 1:1 and 1:1.4. Then the mixtures were heated at different temperatures and decarburized in a microwave heating field. The carbon content of decarburized materials was measured and the apparent activation energy of decarburization reaction was calculated. Experimental results show that as the proportion of calcium carbonate in the mixtures enlarges, the decarburization rate increases, but the heating rate of the mixtures decreases. The decarbonization rate is higher at a higher temperature and for a longer holding time at the same mole ratio. The highest decarbonization rates are 65.56% and 82.96% for both the mixtures decarburized at 1200°C for 60 min, respectively. Carbon activation diffusion and CO2 adsorption diffusion in the high-carbon ferrochrome powders are enhanced in a microwave heating field. Solid-phase decarburization approximates the first-order reaction and the apparent activation energy of decarburization reaction is 68.43 kJ·mol-1.

Li Q.,Beijing University of Technology | Li Q.,Shanxi Engineering Vocational College | Yu Y.,Beijing University of Technology | Chang X.,Taiyuan Heavy Industry Co.
Jixie Gongcheng Xuebao/Journal of Mechanical Engineering | Year: 2012

As a new kind of mechanisms, the compliant mechanism accomplishes the transmission or transformation of motion, force and energy by the elastic deformation of component itself. It is an advanced aspect in the study of the mechanisms. A new dynamic model of compliant links with different loads (end moment or vertical force) is proposed based on 2R pseudo-rigid-body model (PRBM). The kinetic energy and deformation energy are obtained based on the new dynamic model. The dynamic equations of compliant links are derived via Lagrange equation. Compared with the 1R pseudo-rigid-body dynamic model (PRBDM), the equation property and dynamic response of each pseudo-rigid-body dynamic model are analyzed. The superiority of the 2R pseudo-rigid-body dynamic model is presented. The validity of the new model is verified in the example of a planar compliant parallel-guiding mechanism. The numerical results indicate that not only the motion trend but also the internal local deformation of compliant links are described in the 2R pseudo-rigid-body dynamic model. The 2R pseudo-rigid-body dynamic model can be used to show the dynamic behavior of compliant mechanisms and is suitable for the dynamics analysis and design of compliant mechanisms. © 2012 Journal of Mechanical Engineering.

Zhang H.,Shanxi Engineering Vocational College | Li Y.,Northeastern University China
Jinshu Rechuli/Heat Treatment of Metals | Year: 2013

A low-carbon bainitic steel of Mn-Nb-B system was studied. Different TMCP processes was simulated by MMS-300 multifunction thermal simulation testing machine, and microstructure and microhardness of the tested steel were analyzed, so the optimal combination of TMCP parameters was obtained. The results show that, the microstructure of the specimens with deformation of 15%, 30% and 50% is granular bainite, and the specimen with deformation of 50% has a relative finer microstructure and higher hardness. The microstructures of the specimens with deformation temperature of 880, 850, 820 and 780°C are mainly granular bainite. The higher deformation temperature leads to a coarser microstructure, but the amount of ferrite is more in specimen with lower deformation temperature, so the specimen with moderate deformation temperature of 850°C consists of uniform fine granular bainite with a higher hardness.The microstructure of the specimens with final cooling temperature of 600, 550, 500 and 400°C consists of ferrite and bainite. The microstructure of the specimen with a lower final cooling temperature is finer, but there is lath-bainite in the specimen with final cooling temperature of 400°C, while the microstructure is uniform fine granular bainite with relatively higher hardness, when the final cooling temperature is 500°C. So the optimal deformation, deformation temperature and final cooling temperature for the TMCP process are 50%, 850°C and 500°C, respectively.

Liu J.,Nanjing University | Liu J.,Shanxi Engineering Vocational College | Tian Q.,Nanjing University | Huang Y.,Nanjing University | Du L.,Nanjing University
Proceedings - 2012 International Conference on Computer Science and Service System, CSSS 2012 | Year: 2012

This paper explores the feasibility of extracting summer maize using the MODIS EVI time series imagery in Huang-Huai-Hai. We first obtained the spatial distribution of double-season crops based on three-temporal EVI imagery, and then the phenology calendar curves was generated based on the EVI seasonal variation in selected training areas of Huang-Huai-Hai. This curve can be served as a key parameter to separate the summer maize from the double-season crops. Finally, both the spatial distribution and the total area of the summer maize are obtained. The good results suggest that this methodology using MODIS-based EVI can serve as a useful tool to extract the spatial and temporal distribution of summer maize crop at the landscape or regional level. © 2012 IEEE.

Bai L.,Shanxi Engineering Vocational College | Bai K.,Shanxi Engineering Vocational College
Jinshu Rechuli/Heat Treatment of Metals | Year: 2014

The deformation behavior of TC18 alloy was studied by hot compressive deformation method, as well as the microstructure evolution was studied by TEM and EBSD. The results show that flowing curves at 650 ℃ show the recrystallization characteristics with single peak, the increase in deformation temperature the characteristics of single peak weakens and disappears gradually. A lot of recrystallization grains with small size can be observed at 650 ℃ and strain rate of 0.001 s-1. Regular dislocation lays, as well as dislocation cells and the zone without dislocation among dislocation cells can be found at 810 ℃, it is indicated that recovery and recrystallization is coexistence. The EBSD shows that the sub-structures ration in β phase is larger than that in α phase, showing that β prefers to recovery. With the temperature increasing and deformation rate decreasing, the recovery ratio in β phase increases.

Liu J.,Nanjing University | Liu J.,Shanxi Engineering Vocational College | Tian Q.-J.,Nanjing University | Huang Y.,Nanjing University | Du L.-T.,Nanjing University
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis | Year: 2012

In order to give consideration to the change information of summer maize planting area and spatial distribution in Huanghuaihai plain, the present paper combined statistical analysis and remotely sensed classification technology to extract summer maize based on MODIS EVI images. The results showed high accuracy (>67.35%) with the TM-derived in spatial distribution and high correlation coefficient with the agriculture statistics in planting areas at city level (R 2>0.4977). On this basis, change imagery was computed using image overlying algorithm based on binaryzated images derived from classification results in Huanghuaihai plain during 2000-2010. The change detection feature was analysed according to the plates in the region. The results show that the summer maize planting area increased significantly in huanghuaihai plain from 2000 to 2010. The planting area increased steadily in southern part during study year. In the northern part, it discreased from 2000 to 2003 and increased from 2003 to 2010. The most huge change occurred in the northern part in the period of 11 years. The planting proportion increased in the north of plain but decreased in the north. The new method can be widely used in regional dynamic detection and has a good applicability and accuracy.

Niu C.-Z.,Shanxi Engineering Vocational College
ICCASM 2010 - 2010 International Conference on Computer Application and System Modeling, Proceedings | Year: 2010

Aming at the difficulties of detecting clone TPM in DAA protocol using variable basename, a new method to detect clone TPM was proposed, which offers TPM high degree of anonymity. DAA certificate issuer has a new public-key PKN besides primary public-key PK. Every TPM has two certificate: DAA certificate and DAAN certificate, DAA certificate issuer detects clone TPM by DAAN certificate and validates TPM identity by DAA certificate. Analysis and simulation are conducted for our detecting method and exiting proposals. The results show that our detecting method has high detection rate and low leak alarm rate. It is easy that the method can be deployed in those systems that have online TTP. © 2010 IEEE.

Cheng Z.,Shanxi Engineering Vocational College
Advanced Materials Research | Year: 2011

Dry-film and zinc-phosphate (Zn-P) lubricants were compared for potential applications of dry-film lubricant in tube cold forming processes through the twist compression test. Test results showed that the coefficient of friction (μ) had no significant difference between Zn-P soap lube and dry-film lube. The lube coating breakdown time is different between Zn-P soap and dry-film lube. A preliminary industrial trial with dry-film coated tube through the cold drawn over a mandrel showed that the tube surface quality is good and comparable with the Zn-P coated tubes. © (2011) Trans Tech Publications.

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