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TiCN基硬质合金刀具切削性能与切削机理研究 总被引:3,自引:0,他引:3
通过系统地切削试验,研究了TiCN基新型硬质合金刀具在耐磨性、抗冲击性、切削力、刀一屑摩擦系数、加工表面质量等方面的切削性能特点;并通过一定的理论分析,探讨了TiCN基硬质合金综合性能优越的切削机理。研究所得大量切削试验数据及回归经验公式等,可供TiCN基硬质合金刀具推广应用时参考。 相似文献
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Zhen-Xue Liu Jung-Nam Park S. H. R. Abdi Seung-Kyu Park Yong-Ki Park Chul Wee Lee 《Topics in Catalysis》2006,39(3-4):221-226
In this paper, the ethylene adsorption capacities of the nano-sized carbon hollow spheres (CNB) and active carbon (AC), the
Pd (PdCl2) impregnated CNB or AC (Pd/CNB, Pd/AC) and heat treatment under various conditions, were studied at different ethylene concentrations
from 64 to 1060 ppm. The results indicated that AC had a good ethylene adsorption capacity at high ethylene concentration.
Pd impregnation decreased the ethylene adsorption capacity of AC. Heat treatment and H2 activation could increase the ethylene adsorption capacity, but also lowered than AC itself. CNB had lower ethylene adsorption
capacity than AC, but heat treatment and H2 activation could increase its ethylene adsorption capacity markedly. With activating condition from heat treatment in N2 at 300 °C to activation in H2/N2 at 100 °C, to activation in H2 at 200 °C, and to activation in H2 at 300 °C, the ethylene adsorption capacity of Pd/CNB was increased regularly. At low ethylene concentration, viz., 64 ppm,
the ethylene adsorption quantities (q
a) by Pd/CNB activated in H2 at 200 or 300 °C were higher than any other adsorbents. So, activated in H2 atmosphere at higher than 100 °C, Pd/CNB is particularly advantaged for adsorbing low concentration of ethylene. Amongst
all the adsorbents used, Pd/CNB activated in H2 atmosphere at 300 °C for 2 h has the highest ethylene adsorption capacity at lower concentration than 125 ppm. In addition,
all the CNB, Pd/CNB, AC, and Pd/AC samples can be easily regenerated in airflow for more than 3 h. 相似文献
15.
Identification of organochlorines and organobromines in coals 总被引:1,自引:0,他引:1
Xian-Yong Wei Xiao-Hua Wang Zhi-Min Zong Zhong-Hai Ni Li-Fang Zhang Ya-Fei Ji Ke-Chang Xie Chul Wee Lee Zhen-Xue Liu Nai-Bo Chu Jiao-Ying Cui 《Fuel》2004,83(17-18):2435-2438
Four Chinese bituminous coals were extracted with CS2, n-hexane, benzene, methanol, acetone, tetrahydrofuran (THF) and THF/methanol (1: 3 vol/vol) mixed solvent sequentially. The resulting 28 extracts were analyzed with GC/MS. Six organochlorines (OCs) and two organobromines (OBs) were identified in eight extracts from the coals. Our experiments provide, for the first time, the information on the molecular structure of OCs and OBs in coals. 相似文献
16.
Several Mg–Y binary ribbons with Y content up to 17.9 at.% were fabricated by melt-spinning. X-ray diffraction (XRD) revealed that the phase structure changes with increasing Y content from extended solid solution to partially amorphous, and then fully intermetallic Mg24Y5. Anodic potentiodynamic polarization performed in 0.01 M NaCl electrolyte (pH=12) revealed improved anodic passivity behavior compared to pure Mg for all the Mg–Y alloys. X-ray photoelectron spectroscopy (XPS) revealed that the improved passivity of Mg–Y was more related to the elemental oxidation state rather than the concentration of the surface components. To study the effect of Cl− ion on the passivity behavior, anodic potentiodynamic and potentiostatic polarization were performed on Mg–17.9 at.% Y in alkaline (pH=12) NaCl electrolytes containing Cl− ion in the concentration range from 0.00 to 0.50 M. The passive films formed in 0.01 M NaCl electrolyte were similar to the native film, which were composed of MgO and Y2O3. No CO32− and Cl− ions were incorporated into the passive film. The passivity was significantly degraded in the electrolytes containing higher Cl− concentration (0.1 and 0.5 M). Detailed XPS revealed that the surface films under these conditions were composed of much hydrated species Mg(OH)2 and YOOH and/or Y(OH)3 and CO32− was incorporated into the surface film. The incorporation of Y2O3 in the passive film was given as the reason for the enhanced passivity properties of Mg–Y ribbons. The mechanism of Cl− and CO32− ions to the degradation of the passivity was discussed. 相似文献
17.
双余度永磁同步电机有两个余度单元,具有容错率高、体积小、功率密度大等特点,在航空航天、国防、机器人等领域得到广泛应用。针对双余度电机的多目标优化设计问题,基于其典型工作模式,提出二次田口法迭代的多目标优化设计方法。首先,依据双余度度永磁同步电机的应用需求,确定优化目标参数;在初始设计参数基础上,筛选出对目标优化参数影响大的尺寸参数作为优化因子。其次,首次应用田口法筛选出双余度模式下的准最优参数;进而在单余度模式下再次应用田口法对准最优参数进行二次优化;综合两次优化结果确定最终优化参数。最后,通过有限元仿真分析对优化前后的目标参数变化进行验证分析,证明了所提出方法的有效性,也拓宽了对于该类电机的多目标优化设计思路。 相似文献
18.
以原位合成的Al2O3、Al3Zr颗粒增强铝基复合材料作为预熔料,颗粒体积分数为15%,颗粒粒度为2~3μm。在恒温870℃时施加30s频率为20kHz的高频交变电磁场,集肤深度为5.314mm,线圈内输入电流80A,刚玉坩埚置于线圈边缘部位,对应位置处的磁感应强度为0.1T。扫描电镜分析复合材料水淬试样,结果表明,试样中心部位颗粒体积分数基本不变,靠近线圈5mm处颗粒体积分数减少至10%,靠近线圈边缘部分的颗粒体积分数增加至20%,呈现出一定梯度效应,这是电磁挤压力作用的结果。颗粒迁移效率的影响因素有:颗粒体积分数、粒径、熔体温度、磁感应强度、分布及其磁场作用时间。 相似文献
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Ping-Hui Hsu Hui-Ming Teng Yung-Tsan Jou Hui Ming Wee 《Computers & Industrial Engineering》2008,54(3):602-612
The supplier–buyer coordination is an important policy in the supply chain management. The buyer in the two-echelon inventory system with regular selling season has to face the uncertainty of customer demand, supplier’s delivery time and variable price change. At the same time, the supplier has to consider the inventory holding and delay cost. The objective of this study is to develop an integrated supply chain strategy for products with short lifecycle and variable selling price to entice cooperation. The strategy must provide a win–win situation for both the supplier and the buyer. A numerical case example, sensitivity analysis and compensation mechanism are given to illustrate the model. 相似文献