材料期刊网

VARIATION OF SUBSTRUCTURES OF PEARLITIC HEAT RESISTANT STEEL AFTER HIGH TEMPERATURE AGING

R.C.Yang , K.Chen , H.X.Feng , H.Wang

金属学报(英文版)

The observations of dislocations， substructures and other-microstructural details were conducted mainly by means of transmission electron microscope (TEM) and scanning electron microscope (SEM) for 12Cr1MoV pearlitic heat-resistant steel. It is shown that during the high temperature long-term aging, the disordered and jumbled phasetransformed dislocations caused by normalized cooling are recovered and rearranged into cell substructures, and then the dislocation density is reduced gradually. Finally a low density linear dislocation configuration and a stabler dislocation network are formed and ferritic grains grow considerably.

关键词: pearlitic heat-resistant steel , null

DETERMINATION AND APPLICATION OF LARSON-MILLER PARAMETER FOR HEAT RESISTANT STEEL 12CrlMoV AND 15CrMo

R.C.Yang , K.Chen , H.X.Feng , H.Wang

金属学报(英文版)

Based on the analysis and processing on relative empirical formula and data, C-values in Larson-Miller (P) expression, P = T(C + lgt), have determined for pearlitic heat resistant steel 12Cr1Mo V and 15 CrMo (20. 62 and 20. 30). The simulation experiments of high temperature aging, heated from 1.5 to 873 hours, have been designed and performed for its verification. And in combination with published information and the present nearly quantitative works, it has further been verified that both the degradations of microstructures and mechanical properties show a good accuracy and practicability using the Larson-Miller parameter with the present determined C-values. Finally, the effects of carbon content on C-value are analyzed by the empirical electron theory of solids and molecules (EET).

关键词: pearlitic heat-resistant steel , null , null

Chen系统的状态变量周期性反馈控制

李开明 , 李亚洲 , 冯维贵 , 林长

量子电子学报 doi:10.3969/j.issn.1007-5461.2007.05.014

采用非线性反馈控制,用附加了带参数的正弦项对Chen系统进行了有效的控制.随着参数k的逐渐增大,系统的动力学行为呈现出一系列的变化.数值研究结果表明:随控制参数的增大,驱动信号的强度渐大,混沌系统由混沌运动到周期轨道,最终到一相点.

关键词: 混沌 , Chen系统 , 不动点 , Lyapunov指数 , 反馈控制

Ion sputter erosion in metallic glass-A response to "Comment on: Homogeneity of Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass" by L-Y. Chen, Y-W. Zeng, Q-P. Cao, B-J. Park, Y-M. Chen, K. Hono, U. Vainio, Z-L. Zhang, U. Kaiser, X-D. Wang, and J-Z Jiang J. Mater. Res. 24, 3116 (2009)

Journal of Materials Research

The morphology of the dark and bright regions observed by transmission electron microscopy for the Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass strongly depends on the ion beam parameters used for ion milling. This indicates that the ion beam could introduce surface fluctuation to metallic glasses during ion milling.

关键词: room-temperature

K金首饰走俏市场

黄晓霞

黄金 doi:10.3969/j.issn.1001-1277.2004.11.018

以金合金为基体材料或镶嵌各种人工合成宝石而加工制作的K金首饰在颜色、品种、款式等方面都优于纯金首饰,并随着设计及加工工艺水平的不断提高,K金首饰以其个性化、艺术化的创意在市场的份额越来越大.

关键词: 纯金首饰 , K金首饰 , 款式 , 首饰设计 , 制造工艺

K*(892)电磁质量反常

闫沐霖

原子核物理评论 doi:10.3969/j.issn.1007-4627.2001.04.010

电中性的K(892)电磁质量可以大于带电荷的K(892). 这是异乎寻常的现象, 将被称为K-电磁质量反常. 评述了这个课题, 并指出K的质量劈裂可以在北京谱仪(BES)上作精密测量.

关键词: 电磁质量劈裂 , BES实验 , 介子共振态

K-cor夹层结构制备工艺

段沐枫 , 李宁 , 郑莹莹 , 肖军 , 李勇

宇航材料工艺

K-cor是应用Z-pin增强技术的一种新型高性能结构.本文以NHZP-1树脂为基体研究适合K-cor结构的半固化Z-pin拉挤工艺,得到固化度为51.25％的Z-pin为满足制备要求的最佳参数,并制作悬空装置采用两步法进行半固化Z-pin的植入和压弯,探索出压弯和后固化工艺.在此基础上,对试制的K-cor夹层结构进行平拉和剪切试验研究.结果发现,折弯长度是K-cor夹层结构的另一重要参数,较长的折弯长度会增加Z-pin与蒙皮的结合面积从而提高结构的拉伸性能.

关键词: 复合材料 , 半固化Z-pin , K-cor夹层结构 , 制备工艺 , 力学性能

(da)/(dN)与K_1间关系的探讨

陈篪

金属学报

本文证明我们所建议的关系: (da/dN)-C[(△K)~2-K_2~2/K_1~2-(△K)~2]~p能够很好地表达R=(K_(min)/K_(max))=常数时(da/dN)随△K的全部变化,其中P值在1左右,C约在3×10~(-3)—10~(-2)毫米/周之间。

关键词:

Electronic structure and transport properties of K-doped blue bronze Rb0.15K0.15MoO3

Materials Letters

Single crystals of K-doped blue bronze Rb0.15K0.15MoO3 and Rb0.3MoO3 have been investigated by measurements of the X-ray photoemission spectrum (XPS), electrical resistivity and thermoelectric power, respectively. Analysis of the XPS data reveals that two final states representing alternate screening channels coexist in Rb0.15K0.15MoO3. Compared with the pure bronze, the Mo sites of the doped sample contain less 4d electrons which reflected in the movement of Mo3d spectrum. Due to the discrepancy of electronic structure, the K ion doping results in the notable increase of the single particle activation energy and decrease of the thermoelectric power in the charge density wave state. (C) 2007 Elsevier B.V. All rights reserved.

关键词: blue bronze;charge-density-wave;electronic structure;nonlinear transport;k0.30moo3;tl0.3moo3;k0.3moo3;moo3

The effect of yttrium addition on the isothermal oxidation behavior of sputtered K38 nanocrystalline coating at 1273 K in air

Surface & Coatings Technology

The influence of various amounts of Y addition on the isothermal oxidation behavior of sputtered Ni-based superalloy K38 nanocrystalline coating at 1273 K was investigated. The result indicated that the addition of 0.05 and 0.1 wt.% Y in nanocrystalline coating enhanced the selective oxidation of Al, reduced scale growth rate and retarded the phase transformation from metastable to stable alumina. In contrast, 0.5 wt.% Y addition significantly increased the oxidation rate of the coating, the incorporation of Ti in the external alumina scale accelerated the phase transformation to stable alumina. (C) 2007 Elsevier B.V. All rights reserved.

关键词: high temperature oxidation;nanocrystalline coating;reactive-element;superalloy;high-temperature oxidation;oxide scales;percent y2o3;alloys;k38g;superalloy;resistance;diffusion;corrosion;growth