材料期刊网

AN APPLICATION OF SPI TECHNIQUE FOR STUDING STRA DISTRIBUTION AT CRACK TIP

WEI Xuejun ZHOU Xiangyang LI Jin LIU Guanglei KE Wei Corrosion Science Laboratory , Academia Sinica , Institute of Corrosion and Protection of Metals , Academia Sinica , Shenyang , China Institute of Corrosion and Protection of Metals , Academia Sinica , Shenyang 110015 , China

金属学报(英文版)

A computerized digital speckle-interferometry(SPI)system has been set up to determine the in-plane distribution of displacement and strain at crack tip of CF specimens.The principle and the experimental method of this technique are described in detail.The effect of corrosion factors on plastic deformation at crack tip in CF process has been examined by comparing the near-tip strain fields of steel A537 before and after hydrogen charging,and of pure copper before and after applying an anodic current in 3.5% NaCl. The results shows that the clasic finite element mathematical models are not suitable to describe the near-tip deformation under the experimental conditions.Hydrogen charging made the crack tip plasticity decreased for steel A537 and the anodic dissolution enhance the near tip deformation of pure copper specimen.

关键词: speckle-interferometry , null , null

DETERMINATION OF SPACE GROUP OF PrCo_(12)B_6 COMPOUND BY CONVERGENT BEAM ELECTRON DIFFRACTION

WANG Fuhui Institute of Corrosion and Protection of Metals , Academia Sinica , Shenyang , ChinaBIAN Weimin Northeast University of Technology , Shenyang , China Institute of Corrosion and Protection of Metals , Academia Sinica , Shenyang , China

金属学报(英文版)

The space group of PrCo_(12)B_6,compound has been determined using the convergent beam elec- tron diffraction method.The space group is found to be R3m.

关键词: convergent beam electron diffraction , null , null

IMPROVEMENT OF ADHESION BETWEEN ION PLATED TiN COATING AND BASE METAL BY ADDING Y

JIN Zhujing YU Li DAI Shaoxia YU Zhiming Institute of Corrosion and Protection of Metals , Academia Sinica , Shenyang , China Institute of Corrosion and Protection of Metals , Academia Sinica , Wencui Road , Shenyang , China

金属学报(英文版)

The adhesion between the ion plated TiN coating and the base metal is improved by adding Y.The machenism of the effect of Y has been discussed as well.

关键词: ion plated TiN coating , null , null

INFLUENCE OF APPLIED POTENTIAL AND LOADING WAVEFORM ON FATIGUE CRACK GROWTH FOR STEEL A537 IN 3.5% NaCl SOLUTION

LI Jin WANG Zengfu KE Wei Corrosion Science Laboratory , Institute of Corrosion and Protection of Metals , Academia Sinica , Shenyang , China Institute of Corrosion and Protection of Metals , Academia Sinica , Shenyang 110015 , China

金属学报(英文版)

Influence of applied potentials and loading waveform on the fatigue crack growth for steel A537 in 3.5% NaCl solution,and corresponding straining electrode behaviour have been studied.Under the applied potentials over or below -800mV(SCE),the anodic dissolution or the hydrogen embrittlement is predominatant,respectively.For applied anodic potential,the acceleration effect of continuous loading pattern on the CF crack growth mainly appeared at the range of low ΔK values,while for cathodic potential,it appeared at the high ΔK values.The continuous straining causes a decrease of natural potential and an increase of anodic dissolution current.

关键词: corrosion fatigue , null , null , null , null

FATIGUE CRACK PROPAGATION FOR BIAXIAL STRESS CYCLING

PEI Hongxun Institute of Corrosion and Protection of Metals , Academia Sinica , Shenyang , China Institute of Corrosion and Protection of Metals , Academia Sinica , Shenyang , China

金属学报(英文版)

Based on the experimental study of complex biaxial mode Ⅰ fatigue crack growth and the discussion on Von Mises'theory,a new approach is proposed for correlating crack propaga- tion rate under both in-phase and out-of-phase biaxial stress cycling.The results emphasize the contribution of plasticity to fatigue crack growth.

关键词: biaxial stress , null , null , null

Introduction to atmospheric corrosion research in China

Science and Technology of Advanced Materials

In this paper, we introduce the research on atmospheric corrosion in China. We describe the climate characteristics and the classification of atmospheric corrosivity across the whole country. We also describe the rusting evolution under simulated wet/dry cyclic conditions. (C) 2007 NIMS and Elsevier Ltd. All rights reserved.

关键词: atmospheric corrosion;corrosivity;rusting evolution;weathering steels;rust;mechanism;so2;o-3;no2

The use of doped polyaniline as an electrode in the galvanic anodic protection of ferrous metals in industrial acid solutions

Materials and Corrosion-Werkstoffe Und Korrosion

In order to investigate the galvanic anodic protection (GAP) of ferrous metals (such as 410, 304 and 316 stainless steels) in acid solutions by doped polyaniline (PANi), separate doped PANi powder-pressed electrodes with different surface areas (the area ratio of the PANi electrode to stainless steel is between 1:1 and 1:2) have been prepared. These were coupled with ferrous metal in the following solutions: 5 M sulphuric acid, 5 M phosphoric acid and industrial phosphoric acid (containing 5 M phosphoric acid and 0.05% chloride ion) to construct a galvanic cell, in which PANi is cathode while ferrous metal is anode. The results indicate that a PANi electrode with sufficient area can provide corrosion protection to stainless steel in these acidic solutions. A pilot scale coupling experiment was carried out. The results indicate that PANi is a promising material as an electrode for the anodic protection of ferrous metals in acidic solutions in industrial situations.

关键词: conducting polymer-coatings;corrosion protection;stainless-steel;spectroscopy;passivation;performance;mechanism;behavior;primers;films

CORROSION PROTECTION OF Al CATHODES IN ZINC ELECTROLYSIS

F. Lu and WJ. van Ooij( Beijing Institute of Aeronautical Materials , P.O. Box 81-5 , Beijing 100095 , China)( Department of Materials Science and Engineering , University of Cincinnati , Cincinnati , OH 45221-0012 , U.S.A.)

金属学报(英文版)

Zn-Al couple's galvanic coeeosion was a serious problem in acdic ainc sulfate solution .In this paper, a new pretreatment or a coating for Al was developed and tested to protect the Al effectively form corrosion when connected to pure Zinc at electroplating potential,and exposed to an acdic sulfate solution.Corrosion measurement techniques(Galvanic corrosion and DC)were used to investigate galvanic corrosion between Al cathode and Zn anode.It was found out that Al alloy purity and electroplating potential have a large effect on galvanic corrsion between Zn-Al couples.EIS,salt spray test and immersion test were performed to evaluate the method for Al cathodes in zinc electrolyte,BTSE silane pretreatment and polyurethane coating displayed better corrosion protection.Calculation showed the Al dissolution rate is small enough for Al cathode to be used in zinc plants.BTSE treatment or BTSE plus polyurethane coating has the best corrosion performance,and willprotect the Al cathode effectively in zinc electrolysis

关键词: Al-Zn couple , null

Corrosion behavior of metals or alloys with a solid NaCl deposit in wet oxygen at medium temperature

Science China-Technological Sciences

The corrosion of metals or alloys under solid NaCl deposit in wet oxygen (water vapor and oxygen) at medium temperature 400-700A degrees C causes serious damage and has received considerable attention in recent years. Series of mechanistic studies have revealed synergistic interactions between solid NaCl and water vapor, which accelerates the corrosion process. In addition, the overall corrosion process comprises both chemical reactions (oxidation) and electrochemical reactions and their mutual interactions depend on the system of interest. Interestingly, the wet oxygen environment was found to modify the reactions of the element Cr, which plays a useful role in corrosion protection in this special environment.

关键词: synergistic effect;NaCl deposit;water vapor;electrochemical reactions;oxide hydroxide evaporation;plus water-vapor;ni-cr alloys;fe-cr;electrochemical impedance;pure cr;oxidation;chromium;k38g;500-700-degrees-c

Preparation and EIS studies on polyimide/polyaniline blend film for corrosion protection

Polymers for Advanced Technologies

A corrosion protection coating from polyimide/polyaniline (PI/PAn) blend was prepared by solution blending and the anti-corrosion property of this coating was studied with electrochemical impedance spectroscopy technique. The results show that PAn can react with PI to form chemical bonds between these two polymers and these bonds keep these two polymers as a miscible system. The corrosion protection property of this coating increases with a growth in the PAn component and an excellent anti-corrosion effect emerges when the PAn content reaches 10-15%. The reason why PAn can improve the anti-corrosion property is that PI/PAn blend can form a dense and non-porous polymer film that would prevent some corrupting components from access to the underlying steel surface. And also, PAn may serve as a corrosion inhibiting agent to scavenge any protons and foster a local basic surface environment. Copyright (C) 2001 John Wiley Sons, Ltd.

关键词: polyaniline;polyimide;corrosion;EIS