X.H. You
,
Q.L. Zhang and H.G. Guo Taiyuan Heavy Machinery Institute
,
Taiyuan 030024
,
China
金属学报(英文版)
The significance of this paper lies in the application of bending-upsetting 35CrMo steel in train crack-shaft. The hot deforming tests of 35CrMo steel have been done on the Gleeble-1500 testing machine with the deformation temperature at the range of 900癈-1250癈, a strain strain of 0.05 s-1, 0.5 s-1, 1.0 s-1 and compress degree of 15%-80%. Through respectively analyzing and studying the microstructure of the specimen and getting the data from the testing, the results obtained are as follows: the model of flow stress and the stress-strain relationship of material hot deformation, the model of dynamic and static re-crystallization and the correlative references of hot forming parameters and changes of microstructure. The hot deforming stress-strain curses and relevantly re-crystallized micro-structure of 35CrMo steel are drawn at the deformation temperature of 1250 and the strain rate of 1.0 s. Through analyzing and regressive calculating the grain size of the deformation specimen of 35CrMo steel at different locations under the large-deformation and high-temperature conditions, the hot-deforming model of grain calculation is verified. The experimental results and the model of grain calculation can provide scientific basis for analyzing the hot deformation processes and controlling quality.
关键词:
35CrMo steel
,
null
,
null
X.H. You
,
F. Wang
,
L.C. Wang
金属学报(英文版)
A new technique, powder compact foaming process for the production of aluminum
foams has been studied in this article. According to this method, the aluminum powder is mixed with a powder foaming agent (TiH2). Subsequent to mixing, the powder
blend is hot compacted to obtain a dense semi-finished product. Upon heating to temperatures within the range of the melting point, the foaming agent decomposes to evolve
gas and the semi-finished product expands into a porous cellular aluminum. Foaming
process is the key in this method. Based on experiments, the foaming characteris-
tics were mainly analyzed and discussed. Experiments show that the aluminum-foam
with closed pores and a uniform cell structure of high porosity can be obtained using
this method by adjusting the foaming parameters: the content of foaming agent and
foaming temperature.
关键词:
aluminum foams
,
null
,
null
彭启才
,
周心明
,
蔡伯埙
材料研究学报
采用等离子体辉光放电单室系统制备的a-Si:H/a-Si_(1-x)C_x:H 多层膜结构具有低的暗电导和高的光电导特性,且不同于单层膜,有明显的S-W 效应。随着子层厚度L 减小,多层膜曝光态(B)的暗电导率σdB 较退火态(A)的σdA 减小快,即光诱导衰退程度增大,而光电导无明显变化。本文还测定了此多层膜结构的光能隙E_g,得到随子层厚度减小“蓝移”的结果。用一维单量子阱模型作了讨论,实验值与理论计算符合较好。
关键词:
a-Si:H/a-Si_(1-x)C_x:H
,
superlattice
,
amorphous semiconductors electrical properties
,
optical properties
,
null
潘亮
,
程知松
,
范爱琴
,
蔡庆伍
,
郭新文
钢铁
对采用XH轧制法轧制H型钢的轧制力进行分析，以西姆斯公式为基础，采用多元线性回归的方法建立万能轧机轧制H型钢的轧制力数学模型。用编程的方法对数学模型的系数进行求解，给出几种规格的H型钢回归模型的系数，并将计算结果与实测的数据进行对比分析，得到的结果与实测值的误差在6％以内，表明模型具有较高的应用价值。
关键词:
H型钢;数学模型;回归分析;轧制力
潘亮
,
程知松
,
范爱琴
,
蔡庆伍
,
郭新文
钢铁
对采用X-H轧制法轧制H型钢的轧制力进行分析,以西姆斯公式为基础,采用多元线性回归的方法建立万能轧机轧制H型钢的轧制力数学模型.用编程的方法对数学模型的系数进行求解,给出几种规格的H型钢回归模型的系数,并将计算结果与实测的数据进行对比分析,得到的结果与实测值的误差在6%以内,表明模型具有较高的应用价值.
关键词:
H型钢
,
数学模型
,
回归分析
,
轧制力
M. Vergnat
,
M.Gerl+
,
Laboratoire de Métallurgie Physique et Science des Maériaux (U.R.A.au C.N.R.S.No. 155)
,
Universite de Nancy 1
,
France
材料科学技术（英文）
Amorphous Si_(1-x)Sn_x alloys have been prepared by co-evaporation onto substrates maintained at liquid nitrogen temperature. Their atomic structure is investigated using density measurements, scanning high-energy electron diffraction and Mossbauer spectroscopy. The optical and electrical properties are reported. Then, a method to hydrogenate the films during the evaporation process is described and applied to the preparation of amorphous semiconductors from pure silicon to pure tin. Finally, multilayers of type Si / Si:H / ... or Si:H / Si:D / ... are studied. The modulation of hydrogen is shown by low-angle neutron scattering and measurements of hydrogen diffusivity are presented.
关键词:
amorphous alloy
,
null
,
null
张雁
,
蔡庆伍
,
谢广宇
腐蚀学报（英文）
通过扫描电镜（SEM）、透射电镜（TEM）等方法，研究了X65～X70级别管线钢在饱和H2S溶液中的氢致开裂行为，及不同显微组织、位错与析出对氢致开裂（HIC）的作用.结果表明：组织均匀的珠光体/铁素体型X65管线钢和铁素体/针状铁素体型X70管线钢均具有良好的抗H2S腐蚀性能；带状组织是裂纹萌生和扩展的主要途径；合金元素的弥散析出作用可以提高管线钢的抗硫化氢腐蚀性能.
关键词:
管线钢
,
null
,
null
卞留芳
,
张春光
,
陈维德
,
许振嘉
,
屈玉华
,
刁宏伟
中国稀土学报
用等离子体增强化学气相沉积(PECVD) 的方法,以固定的氢气(H2)流量和不同的硅烷(SiH4)和甲烷(CH4)流量比沉积了一系列的氢化非晶SiC(a-SixC1-x-H)膜.用这种宽带隙的a-SixC1-x-H材料作为掺铒的基体材料,通过离子注入的方法得到掺铒的a-SixC1-x-H(a-SixC1-x-H:Er)膜.注入以后的样品经过不同温度的退火.用X射线光电子能谱(XPS)、红外吸收光谱(IR)、拉曼散射谱(Raman)等技术研究不同的SiH4/CH4流量比和退火温度对a-SixC1-x-H:Er发光强度的影响.结果表明,高温退火引起了膜中C的分凝,对铒的发光是不利的.通过低温和室温下铒发光强度的比较,表明这种材料具有较弱的温度猝灭效应.
关键词:
Er
,
SiC
,
硅基材料
,
发光
,
稀土
于青
,
孔凡晓
,
李兰冬
,
武光军
,
关乃佳
催化学报
doi:10.3724/SP.J.1088.2010.91211
首次研究了Pd基催化剂上氢快速选择催化还原NO_x反应(快速H_2-SCR反应).结果表明,Pd/Al_2O_3和Pd/SiO_2催化剂表现出极高的活性,在200℃以上时NO_x转化率可达100%;但Pd/MgO催化剂在整个考察温度范围均没有活性,这表明载体对催化剂快速H_2-SCR活性有决定性作用.与常规H_2-SCR反应相比,快速H_2-SCR反应明显提高了NO_x的消除效率.原位漫反射红外光谱结果表明,快速H_2-SCR反应活性的提高来源于加速生成的氨物种以及后续反应速率的加快.
关键词:
快速选择催化还原
,
钯
,
氢
,
一氧化氮
,
二氧化氮
,
氨
