Tian Sugui, Yang Hongcai, Zhang Jinghua, Xu Yongbo, Hu Zhuangqi. Microstructure and Evolution of A Single Crystal NickelBase-Superalloy During High Temperature Creep[J]. Journal of Materials Engineering, 1998, 0(8): 3-6.
The microstructure in different creep stages have been observed by means of SEM and TEM.The results showed that the change of microstructure had obvious influence on creep resistance in superalloy.The dislocation climb was the micromechanism of tensile creep in Ⅰ and Ⅱ stages.In creep ternary stage creep resistance decreased as a result of large number dislocation cutting into γ′ rafts.The direct reason of creep fracture was cavity and microcrack produced on γ′/γ phase interface by the interaction of the multi-slip.
Meng Liang, Tu Jiangping, Liu Maosen. Study on the Formation of FeS2 Thin Films Prepared by Sulfidation of Fe Layers under Different Temperatures[J]. Journal of Materials Engineering, 1998, 0(8): 7-10.
Experiments were carried out to prepare polycrystalline FeS2 thin films by thermally sulfurating iron layers.The effect of sulfidation temperature on the formation of the FeS2 thin films has been investigated under constant sulfur pressure and annealing time.Test results indicate that more sufficient crystallzation from iron into polycrystalline FeS2 can occur in the range of 400～600℃.The film sulfurated at 400℃ shows more approximate FeS2 stoichiometrical composition and uniform microstructure than that sulfurated at other experimental temperatures.With the elevation of sulfidation temperature,the grain size of FeS2 crystalline increases but the sub-grain size remains constant when the sulfidation temperature is over 400℃.
Xiao Chengbo, Han Yafang. Effect of Silicon on the Microstructure and High Temperature Oxidation Resistance of Yttrium Modified Ni3Al Base Alloy IC6[J]. Journal of Materials Engineering, 1998, 0(8): 11-13.
The effect of different amounts of silicon on the microstructure of the directionally solidified Ni3Al base alloy IC6 modified by proper amount of rare earth element yttrium was studied with scanning electron microscope(SEM).The oxidation resistance of the alloy with different amounts of silicon was tested at 1100℃,the results showed that the oxidation resistance of yttrium modified alloy IC6 was further improved by adding proper amounts of silicon.
Ye Julan, Zhang Lianrong, Li Dongsheng. Application of PVA Synthetic Quenchant to Heat Treatment of Steel Aircraft Brake Parts[J]. Journal of Materials Engineering, 1998, 0(8): 14-15.
In this paper,the effects of operation properties of concentration of PVA quenchant on the 30CrSiMoVA steel aircraft brake parts solutions have been experimentally studied.It is shown that 0.3%～0.5% concentrations PVA solutions satisfy the technical requirments of brake parts.
Zheng Bin, Zhu Yongfa, Yao Wenqing, Wang Hequan, Cao Lili, Hu Weimin. Study of the Metallization and Interface Reaction between Diamond Film and Ti Layer by AES[J]. Journal of Materials Engineering, 1998, 0(8): 16-19.
A Ti layer with a thickness of 250nm was successfully deposited on the surface of a diamond thin film substrate using RF magnetron sputtering technique.The interface reaction between Ti and diamond was promoted by vacuum annealing at the range of 300℃to 600℃.The Auger profile results showed that the width of interface layer was more than 600nm.The formation of TiC at the interface was confirmed by C KLL line shape.The chemical reaction suggested that there was strong chemical bond in interface of Ti/diamond,which was an important factor for the high adhesion strength between metal and diamond.This provided the possibility to produce cutting tools with high performance.The activation energy of the diffusion reaction was 12.3kJ/mol.Ti layer was seriously oxidized when the annealing temperature reached 600℃.To increase annealing time may be a good way to increase the interface reaction.
Liu Daoxin, Ma Zongyao, He Jiawen, Huang Shuju. Metal-induced Embrittlement of Titanium Alloys by Silver and Cadmium and Its Protection[J]. Journal of Materials Engineering, 1998, 0(8): 20-23,27.
Metal-induced embrittlement (MIE) of the titanium alloy Ti-6Al-4V by silver and cadmium was investigated using slow strain rate tests (SSRTs) and dead load tests.The influence of various factors on MIE susceptibility of the alloy was evaluated.The effects of nickel barrier to protect the titanium alloys Ti-6Al-4V and TC11 from MIE were determined.
Cui Lan, Huo Lixing, Zhang Yufeng, Qian Yuedong. A Study on the Grain Charateristic of HAZ of Friction Welded Joint[J]. Journal of Materials Engineering, 1998, 0(8): 24-27.
This paper has studied the grain state of friction welded joint and its influence factors.The results show that the region near the weld is in the state of dynamic recrystallization after welding followed by air cooling.The relationship between the grain size and Zener-Hollomon factor has been analyzed.In addition,welding in intensive specification is favourable to obtaining finer grain and higher toughness of weld.
Cheng Guoan, Liu Honggang, Mao Qiong. Study of Preparation Technique for （Ni,Cr）/Al2O3 Composite Film[J]. Journal of Materials Engineering, 1998, 0(8): 28-30.
The (Ni,Cr)/Al2O3 composite film has been suceesfully prepared by the technique of powder thermal spray.The phases composition and microstructure in the film were determined by using X-ray diffraction analysis and optical microscope.The influence of the preparation technique for (Ni,Cr)/Al2O3 composite film in the powder thermal spray was inverstigated in this paper.The results of the experiments show that the deposition ratio of Al2O3 powder and the spray parameters are important factors that decide the phases structure and the composition of (Ni,Cr)/Al2O3 composite film.
Wang Xiangjian. The Study and Application of Artificial Intelligence[J]. Journal of Materials Engineering, 1998, 0(8): 31-32,35.
The paper introduces the development of several branch in artificial intelligent theory and especially discusses the building of expert-system and the future of the application.
Wang Song, Mo Anlai. Design of Digital System in Ultrasonic Detector[J]. Journal of Materials Engineering, 1998, 0(8): 33-35.
A new digital system of ultrasonic testing has been developed, in which the peak holding circuit and high speed A/D convert are used. It can meet the need of automatic ultrasonic testing with high resolution.
Liu Yingjun. Failure Analysis to the Upper Accessory Drive of an Aeroengine Damaged in Air[J]. Journal of Materials Engineering, 1998, 0(8): 36-38,42.
The failed upper accessory drive of the an-24 aeroengine damaged in air was analyzed,and the trouble-maker was determined as the 2A7000105b ball bearing,made in the former USSR,which was mounted in upper air-oil separator mounting base.When the bearing was out of order,the upper accessory drive will stop working,and finally,the engine should be out in air after hand-feathering.After we adopt a series of measures such as replacing the bearings by new ones,and reinforcing corresponding quality control etc.,similar troubles hasn′t occurred in this place.
Li Baoshan, Niu Yushu, Zhai Xiujing, Zhai Yuchun, Shao Zhongcai. Development, Properties and Applications of Porous Metals(Ⅰ)——Methods for the Preparation of Porous Metals[J]. Journal of Materials Engineering, 1998, 0(8): 39-42.
Methods for the preparation of porous metals,including casting,powder metallurgy,sintering,deposition and high-pressure soakage ect.,have been reviewed systemly in the present paper.The special features and the applied limits of them are introduced.And their advantages and disadvantages are put forward and the corresponding improved measures are suggested.The development direction are pointed out.
Yang Zupei, Zhou Xinshan, Gao Feng, Qu Shaobo, Tian Changsheng. Research Progress of Improving Temperature Stability of Electrostrictive Strain for Relaxor Ferroelectric Ceramics[J]. Journal of Materials Engineering, 1998, 0(8): 43-45,30.
Methods and existing problems of improving temperture stability of electrostrictive strain for relaxor ferroelectric ceramics are reviewed briefly in present paper.
Gao Jintang, Liu Jinzhu, Feng Dapeng, Mao Shaolan. The Systematic Consideration for Design of-High Temperature Lubrication Coatings[J]. Journal of Materials Engineering, 1998, 0(8): 46-49.
In recent years,advanced technologies of aerospace,aviation,atomic energy,etc.urgently need to the use of high temperature lubrication coatings,in order to protect metal surfaces and to enhance efficiency and output power of engine and propeller.In 1980′s,according to the needs of industries and national defenses,lubrication coatings and wearproof materials at high temperature as one of important reasearch directions of tribology had been defined by international tribological academic circles.Typical environments necessarily concerned,key problems and development way in future for design of high temperature lubrication coatings are described in this paper.
