LIU Gu
,
WANG Liu-ying
,
CHEN Gui-ming
,
HUA Shao-chun
钢铁研究学报(英文版)
Plasma surface hardening process was performed to improve the performance of the AISI 1045 carbon steel. Experiments were carried out to characterize the hardening qualities. A predicting and optimizing model using genetic algorithm-back propagation neural network (GA-BP) was developed based on the experimental results. The non-linear relationship between properties of hardening layers and process parameters was established. The results show that the GA-BP predicting model is reliable since prediction results are in rather good agreement with measured results. The optimal properties of the hardened layer were deduced from GA. And through multi optimizations, the optimum comprehensive performances of the hardened layer were as follows: plasma arc current is 90 A, hardening speed is 22 m/min, plasma gas flow rate is 60 L/min and hardening distance is 43 mm. It concludes that GA-BP mode developed in this study provides a promising method for plasma hardening parameters prediction and optimization.
关键词:
plasma transferred arc
,
surface hardening
,
optimization
,
neural network
,
genetic algorithm
陈志钢
,
唐一文
,
张丽莎
,
张新
,
贾志勇
,
余颖
材料科学与工程学报
doi:10.3969/j.issn.1673-2812.2005.04.025
以透明导电玻璃(TCO)、纳米TiO2/TCO、CNTs/TCO、铜片分别为工作电极,用简单铜盐通过阴极还原制备了Gu2O薄膜,并研究了溶液温度和衬底对电化学沉积Gu2O薄膜形貌的影响.结果表明:以TCO和铜片为衬底时,由于表面微粒为微米级,不管溶液温度高低,只能得到微米级的Cu2O薄膜;以纳米TiO2/TCO和CNTs/TCO为衬底,池温高于30℃只能得到微米级的Cu2O薄膜,而池温降到0℃时,都可得到纳米Cu2O.
关键词:
氧化亚铜
,
电沉积
,
溶液温度
,
衬底
徐卫兵
,
戈明亮
,
何平笙
应用化学
doi:10.3969/j.issn.1000-0518.2001.09.011
用熔融插层法制备聚甲醛/蒙脱土纳米复合材料,用X射线衍射研究聚甲醛及复合材料的微观结构,表明复合材料是纳米复合材料.用DSC法研究其非等温结晶行为,对所得数据分别用Jeziorny法、Ozawa法和Liu法进行处理.结果表明,Jeziorny法和Liu法处理非等温结晶过程比较理想.聚甲醛及聚甲醛/有机蒙脱土纳米复合材料的结晶活化能分别为334.6和196.9 kJ/mol,说明有机蒙脱土的加入,降低了聚甲醛的结晶活化能,且t1/z缩短,起到了异相成核的作用.
关键词:
聚甲醛
,
蒙脱土
,
纳米复合材料
,
非等温结晶动力学
王平华
,
徐国永
应用化学
doi:10.3969/j.issn.1000-0518.2004.08.007
用熔融复合法制备聚丙烯/凹凸棒土纳米复合材料,用DSC法研究其非等温结晶行为,对所得的数据分别用Jeziorny法、Ozawa法和Liu法进行处理.结果表明,Jeziorny法和Liu法处理非等温结晶过程比较理想.聚丙烯及聚丙烯/凹凸棒土纳米复合材料的结晶活化能分别为194.1和162.8 kJ/mol,表明凹凸棒土的加入,降低了聚丙烯的结晶活化能,且t1/2缩短,起到了异相成核作用.
关键词:
聚丙烯
,
凹凸棒土
,
纳米复合材料
,
非等温结晶动力学
李强
,
宣益民
工程热物理学报
建立了测量小通道扁管内纳米流体流动与对流换热性能的实验系统,测量了不同粒子体积份额的水-Gu纳米流体的管内对流换热系数和摩擦阻力系数,实验结果表明,在相同雷诺教条件下,小通道扁管内纳米流体的对流换热系数大于纯液体,且随粒子的体积份额的增加而增大,而纳米流体的阻力系教并未明显增大.
关键词:
纳米流体
,
强化传热
,
小通道扁管
Scripta Materialia
A recent comment on a previously published paper addressed the invalid explanation of the off diagonal interdiflusion coefficients of the beta-Ni(Al,Cr) phase in the Ni-Cr-Al system according to the symmetric property of the thermodynamic matrix. In this paper, the experimental data presented by Hou et al. was reanalyzed and the interdiffusion coefficient matrix was estimated again. The results of the analysis have been discussed in terms of a brief reply to the comments of Liu and Liang. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
关键词:
Diffusion;Intermetallic compound;Ni-Cr-Al
邓超
,
邵玮
,
李春忠
高分子材料科学与工程
采用元机纳米锑掺杂二氧化锡(ATO)和有机聚醚酯(PEE)协同提高聚时苯二甲酸乙二酯(PET)的抗静电性能,合成了聚对苯二甲酸乙二酯-聚醚酯/锑掺杂二氧化锡纳米复合材料(PET-PEE/ATO).使用Czawa方程和Liu-Mo方程研究了PET-PEE/ATO纳米复合材料的非等温结晶过程.Ozawa方程研究发现,在非等温结晶过程中,PET、PET-PEE、PET/ATO、PET-PEE/ATO的成核性能依次提高.Liu-Mo方程发现,ATO和PEE的加入分别促进了异相成核作用和加快了结晶生长,PET-PEE/ATO结晶成核性能最好,结晶速率最快.
关键词:
聚对苯二甲酸乙二酯
,
有机聚醚酯
,
无机纳米锑掺杂二氧化锡
,
纳米复合材料
,
非等温结晶动力学
董企铭
,
苏娟华
,
刘平
,
李贺军
,
康布熙
材料热处理学报
doi:10.3969/j.issn.1009-6264.2004.03.010
通过能谱和透射电镜分析研究了Gu-0.3Cr-0.15Zr-0.05Mg合金的时效析出,在4790℃时效4h形成了有序的原子排列,其化合物类型为CrCu2(ZrMg);同时存在体心的Cr相和面心的Cu4Zr相,在晶界上有少量未溶的Cr粒子.细小弥散的析出相使合金的性能得以提高,470℃时效4h～6h,硬度和导电率分别达109～108HV,79%IACS～80%IACS.
关键词:
Cu-Cr-Zr-Mg合金
,
微观组织
,
析出
,
时效性能
李增峰
,
汤慧萍
,
刘海彦
,
黄愿平
中国材料进展
doi:10.3969/j.issn.1674-3962.2006.01.006
采用机械活化制粉、低温烧结和致密化处理,制取了不同Ni含量的Mo-Gu合金.研究了Ni对Mo-Cu合金的致密性、膨胀系数、导热和导电性能的影响.结果表明,添加活化元素Ni使Mo-Cu合金的烧结致密化温度降低,热膨胀系数的变化与Al2O3陶瓷的变化很吻合,导电和导热性能降低,显微组织细小均匀,成为网络结构,是一种与Al2O3陶瓷封接匹配得很好的电子封接材料.
关键词:
Mo-Cu合金
,
活化元素
,
致密化
,
膨胀系数
,
导热系数
