Li Guoqiang, Li Di. Rare-earth Conversion Coating for Aluminum Alloys[J]. Journal of Materials Engineering, 1998, 0(7): 3-5,8.
Rare-earth conversion coatings for aluminum alloys shows a good developing prospect due to excellent anti-corrosion and non-toxic property of the applied process. This paper reviews the development for rare-earth conversion coatings on aluminum alloys.
Yang Zhelong, An Maozhong, Fang Haitao, Zhang Jingshuang, Tu Zhenmi. Effect of Rare-earth Additives on Hard Anodizing of Aluminium Alloy[J]. Journal of Materials Engineering, 1998, 0(7): 6-8.
Effect of rare-earth additives on hard anodic oxide coatings of aluminium alloy are studied. Rare-earth additives RE-1 and RE-2 can improve the forming rate,microhardness and the resistance to wear of aluminium alloy LY12 oxide coatings.Because rare-earth additives would increase the forming valtage,then thickness of hole wall can be increased, and porosity of the film can be decreased.The properties of oxide coatings are improved.
Lu Feng, W. J. van Ooij. Protection of Al2024 Aluminum Alloys by Rare Earth Compound Inhibitors[J]. Journal of Materials Engineering, 1998, 0(7): 9-11.
The research has been focused on finding an alternative to chromium-base compounds for use in Al2024 alloys inhibitor formulations. These inhibitors for surface protection of aluminum alloys are various cerium or lanthanum salt solution, for Al2024 treated by immersion in cerium acetate or lanthanum acetate solution with different time, using DC electrochemical corrosion measurement technique, good corrosion resistance surface were found, the concentration of Ce3+ or La3+ is only 50～100×10-6, the results were also compared to CrO3 and Na2CrO4 solution at same concentration. Since rare earth salts is environmentally-compliant and produces exceptional corrosion resistance, it should be considered as a candidate for the replacement of chromate inhibitors.
Li Jianping, Wu Fengjun, Li Weiguang. Study of Protective Performance of HY3 Coating on DZ125 Superalloy[J]. Journal of Materials Engineering, 1998, 0(7): 12-14.
Resistance to oxidation and corrosion of NiCrAlYSi coating on DZ125 super alloy is researched in this paper. The results show that the NiCrAlYSi coating has good protective performance of DZ125 superalloy against cycling oxidation at 1100℃ and 1050℃ and can enhance property of DZ125 superalloy against gas hot corrosion resistance at 900℃.
Li Weiguang, Wu Fengjun, Li Jianping. Study of MCrAlX Coating Contained Hf[J]. Journal of Materials Engineering, 1998, 0(7): 15-17.
NiCoCrAlYHf coatings have an excellent performance on the oxidation resistance under the oxidation test at 1150℃. The studies have indicated that the existence of Hf oxide play an important role for improving the stability of coating with protective oxide film and the ability of oxidation resistance. The reason is that the Hf oxide mainly distribute to the boundary of Al2O3 oxide film and coating.
Liu Haiping, Wang Xiaohong, Hao Shanshan, Feng Zixiu, Hao Mengyi. Oxidation of Ti60 Alloy and Its protection by NiCrAlY Coating[J]. Journal of Materials Engineering, 1998, 0(7): 18-20,14.
The oxidation behavior of the Ti60 alloy with and without an ion plated NiCrAlY coating was observed. A thick oxide scale grew on the naked alloy accompanying an oxygen dissolution induced embrittlement zone within the alloy subsurface. The thin NiCrAlY coating could not deter the development of titanium oxide on the surface and Kirkendall voids were readily detected at the alloy/coating interface. When the coating was as thick as ～13μm,the oxidation caused by the titanium outward diffusion was eliminated and the coating itself showed an excellent oxidation resistance. However,a thick interdiffusion zone was evident at the alloy/coating interface which suggested a poor chemical stability of this coating on titanium based alloys.
Zhang Xiaoyun, Li Bin, Zhang Jiansu, Shen Wenyan. Eletrochemical Analysis on Corrosion of Forced Oil Pipeline in Combustion Chamber[J]. Journal of Materials Engineering, 1998, 0(7): 21-22.
The present article describes the reason of GH1140 alloy oilpipe pitting in HCl+H2SO4+CuSO4 is caused by Fe2+ concentration cell. The conclusion is based on the electrochemical polarization technique and chemical analysis. It has been put forward that the preliminary plan prevented pitting.
Liu Youhou, Jing Yulan, Hu Ruoying. Wear Resistance Tests of Hard Anodic Coating on Aluminum Alloys[J]. Journal of Materials Engineering, 1998, 0(7): 23-24,29.
Three test methods for wear resistance of hard anodic coatings on aluminium alloys,whic are the abrasive wheel wear test method, abrasive jet test method and the Taber abraser test method,have been reviewed in the present paper. Various influence factors for the Taber abraser test have been emphatically reviewed.
Liu Shunguo. The Effect of the Status of the Piston Surface on the Roughness of the Anodic Oxide Film[J]. Journal of Materials Engineering, 1998, 0(7): 25-26.
This paper analyzes the roughness of the surface oxide of after the piston surface is treated by hard anodizing,and explains the means by which even oxide film can be obtained.
Zhang Jiansu, Liu Haiping, Hao Shanshan. High-temperature Erosion Resistance Properties of ZrN[J]. Journal of Materials Engineering, 1998, 0(7): 27-29.
The erosion resistant property of ZrN hard coating is studied in 300℃. It was shown that ZrN coating has high binding power,microhardness,and erosion resistance. It can be used to improve the erosion resistance of Ti alloys highly.
Li Songmei, Guan Shan, Hu Runan. The Electroless Plating Process for Nickel with High Depositing Speed and Stable Electrolyte[J]. Journal of Materials Engineering, 1998, 0(7): 30-33,43.
The effect of the constituents of the nickel plating solution were studied,ie the nickel salt,reducting agent,complexing agent and accelerating agent ect on the depositing rate. The processing procedure was determined and a new type BH electroless nickel plating procedure was selected succesfully. With this processing procedure,the deposite rate can reach 25μm/h and over. The life time of the solution can last more than 7 periods. The phosphor content was analyzed with an EDAX attached to a SEM. The result abtained from the X-ray diffraction analyzer showed that the partern of the deposited layer was a typical non-crytal structure. The examination of the deposit properties indicated that the hardness and the abrasion resistance of the deposit were relative high,the corrosion resistance of it was superior to 1Cr18Ni9Ti stainless steel.
Shen Wei. Electroless Amorphous Coatings and It's Application Engineering[J]. Journal of Materials Engineering, 1998, 0(7): 34-37.
The current level of development in electroless nickel plating and its application in aviation and aerospace industry are surveyed for recent advances.Topics covered include academic research,state of the arts,equipment automatization and environmental concerns. A technology for extension the bath life by electrodialysis method with ion exchange diaphragm is also discussed.
He Shihuan, Chen Junwu, Liu Ranzhe, Zhang Jianguo. Process and Application of Mechanically Plate ZnSnAl Alloy[J]. Journal of Materials Engineering, 1998, 0(7): 38-40.
The process and application of mechanical plating with ZnSnAl alloy were introduced.This coating had better corrosion resistant than electroplated Zn and good adhesion onto a substrate. No hydrogen embrittlement could be caused.
Lai Junbin, Li Jiazhu. Structure Design of Data-base & Expertise Consulting System for Environmental Tests of Aeronautical Materials[J]. Journal of Materials Engineering, 1998, 0(7): 41-43.
his paper introduces the situation of investigation for data-base, describes the structure designs of data-base & expertise consulting system for environment tests of aeronautical materials.
Chen Shiming, Peng Xiren. The Potential and Ways of Electroplating Clean Production[J]. Journal of Materials Engineering, 1998, 0(7): 44-46.
In this paper,the background of clean production emergence has been introduced on the basis of the changes of industrial pollution prevention policies.The potential of clean production has been analysed in electroplating trades. Further,the ways of implementation of clean production are proposed briefly.
