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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. Source

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. Source

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. Source

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. Source

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. Source

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