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J. Cent. South Univ. Technol. (2009) 16: 0066-0072 DOI: 10.1007/s11771-009-0011-9 Synthesis and property of temperature and pH sensitive xanthan–MA/PNIPAAm hydrogels LONG Qing-de(隆清德), PAN Chun... property. And maximum swelling ratio, swelling kinetics and temperature response kinetics were studied. The data obtained clearly show that these smart hydrogels are responsive to the external changes......
of 0.01-10 s-1, deformation temperature range of 250-450 °C and a true strain of 0.6. The constitutive relationships among flow stress, strain rate and deformation temperature were described by Arrhenius-type equations, based on the fact that the material constants could be calculated under a wide range of strains. The results show that the flow stress of the experimental alloy decreases......
. The experimental results shows that 2A70 aluminum alloy is a kind of aluminum alloy with the property of dynamic recovery; its flow stress declines with the increase of temperature, while its flow stress... that the model constructed by BP ANN can accurately predict the flow stress of the 2A70 alloy. Key words:2A70 aluminum alloy; flow stress; constitutive relationship; BP artificial neural network; [全文内容正......
molten pool with different flow rates of pure nitrogen 2.1.2 组织与物相 图4所示为纯氮气气流量15 L/min时渗氮层不同部位组织SEM像.图4(b)~4(e)所示分别为从渗氮表层到基体热影响区的组织放大图,组织依次为粗大的胞状树枝晶,等轴晶,细小的胞状树枝晶和针状晶.其中,胞状晶发展的一次枝晶臂来自于同一个晶粒,结晶取向一致.表层...31.0%(摩尔分数),细枝晶为20.3%,枝晶间为4.2%(见图6(a)). 图7所示为纯氮气不同气流量时渗氮层表面的XRD谱.由图7可知,气流量5 L/min渗氮后渗氮层的相组成为TiN和α-Ti,15 L/min渗氮后渗氮层的相组成为TiN. 图3 渗氮层熔体流动示意图 Fig. 3 Diagram of melt flow in nitriding layer 图4......
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s-1. The microstructural evolution of the alloy was investigated by optical microscopy. The results indicate that the flow stress of the alloy increases with increasing strain rate and decreasing deformation temperature. The flow stress increases with increasing strain until the stress reaches the peak value, then the flow stress remains constant. The flow stress in deformation can be described......
deformation temperature and decreasing strain rate. The constitutive equation for flow stress of Q345E is formulated by Arrihenius equation and the modified Zener-Hollomon parameter considering the compensation of both strain and strain rate. The flow stress values predicted by the constitutive equation agree well with the experimental values, realizing the accurate prediction of the flow stress of Q345E......
words: magnesium alloys; anodization; electric parameters; property 镁合金具有密度小, 比强度, 比刚度高, 电磁屏蔽性, 减震性好以及优良的切削加工和抛光性能, 在航空, 汽车和3C产品领域具有很大的应用潜力[1-4]. 但是其耐蚀性较差, 制约了镁合金的广泛应用. 镁合金常用的防护方法有电镀/化学镀, 化学..., 2005, 34(10): 1554-1557. GUO Hong-fei, AN Mao-zhong, XU Shen, et al. Effects of current density on mechanism of micro-arc oxidation and property of ceramic coating formed on magnesium alloys[J]. Rare......
Trans. Nonferrous Met. Soc. China 25(2015) 3399-3409 CFD-supported optimization of flow distribution in quench tank for heat treatment of A357 alloy large complicated components Xia-wei YANG1, Jing.... School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China Received 9 December 2014; accepted 4 May 2015 Abstract: The flow distribution in quench tank for heat......
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