XIAO Cheng-bo, HAN Ya-fang, ZHANG Xing-an. Study on Directionally Solidified Ni3Al Based High Temperature Structural Material IC6A Alloy[J]. Journal of Materials Engineering, 2001, 0(6): 3-6.
The microstructure of the directionally solidified Ni3Al based alloy IC6A was studied with scanning electron microscopy(SEM), transmission electron microscopy(TEM), energy dispersive spectrum(EDS) technique of electron probe micro-analyzer(EPMA) and X-ray diffraction technique.The results show that the regions consisted of Ni3Y,Mo1.24Ni0.76 and γ phases and surrounded by large size γ′ phases precipitate in the interdendritic areas of alloy IC6A when the content of yttrium is near to the upper limit. The main physical properties, cyclic and static oxidation resistance at 1100℃, high temperature stress rupture properties and creep properties at different temperatures, high temperature thermal fatigue and high cycle fatigue properties, tensile properties and impact toughness at different temperatures of alloy IC6A were calculated to meet the needs of aero-engine tubine vanes. The results show that the oxidaton resistance of alloy IC6A is substancially improved due to the presence of proper amount of yttrium. Compared with alloy IC6, the stress rupture properties, creep resistance, impact toughness, thermal fatigue and high cycle fatigue properties of alloy IC6A are also improved. Alloy IC6A is a high temperature structural material suitable for manufacturing the aero engine turbine vanes with the operating temperature equal to or below 1100℃.
SHU Wu-bing, QIAO Sheng-ru, BAI Shi-hong, LÜ Bao-tong, LI Mei. Research on Morphology and Deposition Mechanism of Pyrolitic Carbon in Rapid Densifing C/C Composites[J]. Journal of Materials Engineering, 2001, 0(6): 7-9,6.
The analytical results for the pyrolytic carbons made from kerosene (Ck),gasoline(Cg),diesel oil(Cd)and cyclohexane(Cc)with XRD shown that the graphitization degree of these pyrolytic carbons was on the sequence of Ck>Cd>Cg>Cc, SEM micrographs indicated that the pyrolytic carbons was orderly aggregated on the mechanism of nucleation-growth. The carbon fiber and carbon black produced in pyrolyzing precursors were the crystal seeds which promoted the deposition of the pyrolytic carbons.
ZHU Li-juan, TANG Meng, YU Bao-hai, LIU Yue, TIAN Yan-wen, ZHAI Yu-chun. Investigation on Sinter Process of TiC/NiCrMoAlTi Cermet[J]. Journal of Materials Engineering, 2001, 0(6): 10-12.
The sintering process of TiC/NiCrMoAlTi cermet is studied by DTA. It is found that the compounds of Ni3Al,Ni2Al3,NiAl and Ni3Al are formed at 590℃~665℃ by the reaction of Ni and Al, and then, the liquid phase emerges with the increasing of temperature to 1400℃, and the compounds, except for NiAl, are dissolved in the form of [Ni] and [Al], the intermetallics are formed during the cooling process in NiCr phase. The liquid phase was formed at about 1330℃.
WANG Xiao-dong, LI Ting-ju, JIN Jun-ze, YU Yan, LIU Jun-jiang, XU Hai-cheng, CHEN Yi-wen. Effect of Electromagnetic Driver Force on Solidifying of Billet[J]. Journal of Materials Engineering, 2001, 0(6): 13-15,20.
In this experiment, lower melting point Sn+3.5wt%Pb alloy was served as experiment material, through experiment simulating finite electromagnetic stirring of continuous casting of steel, effect of electromagnetic driver force on the solidifying process of billet was researched. The results show that under electromagnetic driver force, there is a boundary layer in the semi-solid zone, the boundary layer is the maximum zone of electromagnetic force affecting on the metal molten. Velocity of melt within boundary layer is increased with electric current in coil increasing, but no affecting is on the melt beyond boundary layer. Electromagnetic stirring pushes the boundary layer out symmetrically, and makes the solidifying shell thickness thinner. Meanwhile, the growth of dendrite is counteracted; prominences on the interface become smaller and even escape.
ZHOU Shao-rong, QIAO Sheng-ru. Study of Flexural Properties of C/C Composite at High Temperature[J]. Journal of Materials Engineering, 2001, 0(6): 16-17,29.
Flexural properties of C/C composites was investigated at the temperature of 20℃ to 1400℃. It's found that as the span-to-depth ratio increases, the bending strength rises but the shear strength reduces. When the span-to-depth ratio is greater than 8, the bending strength tend to be constants. The span-to-depth ratio is independent on temperature in the range of 20℃ to 1400℃.
LIU Yao-wen, CHEN Quan-de, HAN Shun-chang. Effect of Artificial Aging on the Damping Property of the Cast ZA27Ce Alloy[J]. Journal of Materials Engineering, 2001, 0(6): 18-20.
The Measurement of the damping property to the artificial aging ZA27Ce alloy at 250℃ showed that the heat treatment could improve the damping property of ZA27Ce alloy. The microstructures of the as-cast and as-heattreated the alloy were observed in detail by the use of TEM. The sufficient solid phase transformation and fully spinodal decomposition played the important role on the improvement of the damping property of the ZA27Ce alloy.
GAO Shan, SUN Feng-li, YUAN Gang-shan, MA De-liang. The Study of Platinum Recovery by PdNi5 Alloy Catchment Gauzes in Nitric Acid Plants[J]. Journal of Materials Engineering, 2001, 0(6): 21-23,26.
The adsorption and diffusion behavior of the platinum on the surface of PdNi5 alloy catchment gauzes were investigated under the condition of producing nitric acid. The mechanism involved in recovery of platinum was briefly discussed.
ZHAO Xi-hong, TAN Yong-ning, YU Qian. The Microstructure and Properties of the TiB2-Particle Strenghthened NiAl-based Alloy[J]. Journal of Materials Engineering, 2001, 0(6): 24-26.
The microstructure and properties of the TiB2-particle strenghthened NiAl-based alloy were discussed.The particles of TiB2 were generated in one step during pouring process by the addition of B and Ti according to the stoichiometry. It is discovered that the distribution of TiB2 particles is related to the heat treatment of the material and the phases appearing in the alloy. The shapes of the particles existing in each phase are different. The particles and the matrix are badly connected on their interface and there is no orientation relationship between them.
SHEN Chao. Experiment on 3232/Rc10 800 Prepreg Tape[J]. Journal of Materials Engineering, 2001, 0(6): 27-29.
The effect of impregnating process parameters on prepreg tape quality has been studied by using 3232 mid-temperature curing epoxy resin and Rc 10 800 glass fiber. The qualified prepreg tape has been produced.
WANG Yi-qing, TANG Yi-ping, ZHAO Wen-zhen, LU Bing-heng. Mold Manufacturing Method Combining Electro-forming with Arc Spraying[J]. Journal of Materials Engineering, 2001, 0(6): 30-32.
A special method for manufacturing molds through integrated arc spraying with electro-forming was investigated.The results show that the mold manufacturing method of combining electro-forming with arc spraying can save 60%~80% manufacturing cycle and 80% cost relative to pure electro-forming. The hardness of the mold can reach HV600 by optimizing the electro forming parameter. The performance of the mold can be greatly enhanced compared with pure arc spraying mold. This method can eliminate the tedious measuring process on the original model and can perfectly copy the dimension and surface morphology of the model.
QU Xuan-hui, WEN Hong-yu, ZHENG Zhou-shun, AO Hui. Computer Simulation of Powder Injection Molding Process[J]. Journal of Materials Engineering, 2001, 0(6): 33-36.
The main recent achievements in the computer simulation of powder injection molding process are reviewed, including mathematical models, controlling equations and numerical methods. Their merits and demerits are analyzed and compared. The main trends and directions in this field were proposed.
ZHANG Jian-guang, HAN Jie-cai, HE Xiao-dong, DU Shan-yi. Rapid Prototyping Technique for Fabricating Ceramics[J]. Journal of Materials Engineering, 2001, 0(6): 37-40.
Principle,processing,and characteristics of rapid prototyping(RP) used for fabricating sophisticated ceramic objects,such as laminated objected manufacturing(LOM),fused deposition modeling(FDM),shape deposition modeling(SDM),stereo-lithography(SLA),selective leser sintering(SLS),ink jet method(IJM), are reviewed The results show that the RP has potential to fabricate sophisticated ceramic objects,such as, structural ceramics,functional ceramics,biological ceramics,and piezoelectrical ceramics. The quality of RP ceramics are compared well with that of conventionally processed ceramics.
HE Feng, WANG Wu-xiang. Research and Application of Warm Compaction in Powder Metallurgy[J]. Journal of Materials Engineering, 2001, 0(6): 41-43,47.
The characteristics of warm compaction process and its densification mechanism is introduced. The choice of warm compaction process parameters and the properties of warm compaction materials is described. Also the addition method and the selection principles of polymers is discussed Future research trends and the potential application of warm compaction is presented.
WANG Gai-lian, WU Cui-wei, DONG Jian-xin, XIE Xi-shan. A Research Progress of α-Cr Phase Precipitation in IN718 (GH169)[J]. Journal of Materials Engineering, 2001, 0(6): 44-47.
A research progress of α-Cr phase precipitation in IN718 from abroad has been briefly reviewed. Some research work dealing with α-Cr in IN718 (GH169) in China have been shown as well. Some important items, which should be studied on α-Cr precipitation, have been indicated.
