F. H. Froes, C. Suryanarayana, D. Eliezer. Production, Characteristics and Commercialization of Titanium Aluminides[J]. Journal of Materials Engineering, 1991, 0(4): 1-9.
The production, characteristics, and commercialization of monolithic and composite titanium aluminides are presented with emphasis on use in the demanding aerospace industry. The attractive elevated temperature properties combined with a low density are attractive, but inherently low "forgiveness", and environmental concerms, must be overcome before wide-spread use will occur.
Xu Changgan, Liu Lingxia, Tang Zhenting. Research on Brittle-toughness Transition Temperature of 30CrMnSiNi2A Steel[J]. Journal of Materials Engineering, 1991, 0(4): 10-13.
The brittle-toughness transition curves of 30CrMnSiNi2A Steel on a Pandulum impact testing machine with computering search and treatment of data. The Criterion of determenation of brittle-toughness transition is raised. It is usually hard to determine the brittle-toughness transition temperature because of continuous change of impact energy with the test temperature without point of sudden change, but this method described in this paper resolved the difficult problem.
Li Xiaofeng, Han Yafang, Xia Mingren. Investigation of the Relation Between the Microstructure, Mechanical Properties and the Sintering Processes of Ceramic Foam Filter[J]. Journal of Materials Engineering, 1991, 0(4): 14-16.
The ceramic foam filters composed of about 80 wt% aluminum oxide have been produced. The effect of sintering temperature and holding time on microstructure and mechanical properties have been studied. The physical and mechanical properties as well as its’ thermal expansion under static load of the filter have been tested. The analyses of the relation between the microsturcture, properties and sintering processes, showed that the Tamman Temperature of the filters is abour at 1400℃, and when the filters were sintered for 2~4 hours at 1500~ 1600℃, solid-state reactions and sintering were almost copleted, the properties at high and room temperature, and the stability at high temperature were fair reasonable.
Chen Jiankang, Tu Pingliang, Zhou Jianchu. Thennochemically Formed Metallic Ceramic Coatings——A Valuable New Development of Coating Technology[J]. Journal of Materials Engineering, 1991, 0(4): 17-20.
In this paper, the properties, developments and prospective applications of thermochemically formed metallic ceramic coatings were reviewed. Some results of. authors were reported, some key problems of this new technology were discussed.
Mai Kancheng, Zeng Hanmin, Zhang Rongzhong. The Compatibility and Phase Separation of ATS/PEK-C Blends[J]. Journal of Materials Engineering, 1991, 0(4): 22-24.
The compatibility and phase separation of blends prepared from acetylene-terminated sulfone (ATS) and phenolphthalein polyarylethyl ketone (PEK-C) were studied by torsional braid analysis (TBA) and SEM. Uncured ATS/P.EK-C blends are compatible systems. The addition of ATS decreases the Tg of PEK-C. The Tg of blends depends upon the ATS contents. On curing phase separation occurs to form two phase structures. The degree of phase separation depends upon the cure conditions.
Gan Yongxue, Chen Biankun. Bending behaviour of Carbon Fiber Reinforced Copper-5% Tin Composite Material[J]. Journal of Materials Engineering, 1991, 0(4): 25-28.
The bend strength of carbon fiber reinforced copper-5% tin composite material made by hot pressing had been measured. The result shows that bend strength a increases with the increasing in carbon fiber volume content Vfandthe relation can be expressed appromatively by a regressive formula:σ=94.5-421Vf+1557Vf2(MPa). The composite is superior to iron based frictional material prepared by powder metallurgy in bending. The "pulled out" type fracture of the composite was also observed by the use of electro scanning microscope. Moreover, a possible bending fracture process was deduced.
Chai Xiengguo, Guo Yajun. Compressive Testing for Impacted Composite Laminates[J]. Journal of Materials Engineering, 1991, 0(4): 29-31.
Compressive testing equipments and method for impacted composite laminates are described in this paper, which are consistent on the whole with NASA RP 1142, 1985. This method can be used in quality controlling, appraisal and strength design of composites. It is also a new means for the study of damage mechanism of composite laminats.
Qiao Shengru, Zhou Jun, Xi Shoumu, Wang Hong, Zheng Xiulin. New Technique for Manufacturing Grainular Composite and Its Wearing Behaviour[J]. Journal of Materials Engineering, 1991, 0(4): 32-35.
In the present study, a new technique has been developed for manufacturing the grainular composite. The process of the manufacture is as follows:firstly, the SiC particles (3~6um) or graphite are put into melten aluminium alloy (Al-1.8Si-0.4Mg-0.36 Cu); then, the melten alloy containing the SiC or graphite grains is stired and quickly cooled to obtain the prefabncated subsance in the states of grains of 0.3~1.0mm diameter containing a few particles of SiC or graphite, or both; finally, the prefabricated substance of three kinds are, respectively, sifted and pressed at 620C and 20 MPa pressure for 2~5 minutes to form the grainular composite. The whole process is protected from the oxidization of aluminium by using nitrogen. The observation under optical microscope and SEM shows that the particles of SiC or graphite are distributed homogeneously in the alloy matrix and banded well with the matrix. The composite reinforced by SiC grains has the best wearing resistance but the composite reinforced by graphite has the worst wearing resistance. The wear mechanism operated in the abovementioned composites are mainly adhesive.
Zheng Ziqiao, Cui Qi. Effect of Heat Treatments on the Microstructure and Mechanical Properties of an Al-Li-Cu-Mg-Zr Alloy[J]. Journal of Materials Engineering, 1991, 0(4): 36-38.
Effect of various heat treatments on the precipitation and tensile properties of an Al-Li-Cu-Mg-Zr alloy was investigated by observation of microstructure and tensile test at room temperature. The results show that the strength and ductility were significantly improved in T8 condition. The intermediate thermomechanical treatment (ITMT) caused the incresment of ductility and a less improvement in strength. The low strength and poor ductility were observated in T6 treatment. The relation of properties to heat treatments and microstructure was discussed.
Tang Jinrong, Yu Shengke. Investigation of the Joint Characterization for Al/Ti Resistance Spot Welds[J]. Journal of Materials Engineering, 1991, 0(4): 39-41,13.
This paper describes the results to research the joint characterization for resistance spot welds of aluminum and its alloy to titanium alloy. These joints were checked by metallography, electron probe microanalysis and mechanical tests. Fracture behavior was characterized with scanning electron microscopy. It was shown that sound joints can be produced by melting the aluminum onto hot (not melten) titanium surface. These joints have excellent static tensile strength.
Li Xiangbin, Wang Renzhi. Effect of Shot Peening on the Fatigue Properties of Disc Spring[J]. Journal of Materials Engineering, 1991, 0(4): 42-43.
The distribution of residual stresses after shot peening and fatigue testing of disc springs and the effect of residual stresses on the fatigue strength of springs have been investigated in the present paper.
Pan Tang. Rapid Determination of Pb, Sn and Mo in 245 Friction Material by AAS[J]. Journal of Materials Engineering, 1991, 0(4): 46-48.
A method for the determination of Pb, Sn and Mo in 245 friction material by AAS has been developed. The optinum conditions of determination and the influences of the amounts of HCl and H2O2, iron and coexisting elements on the determination of Pb, Sn and Mo in 245 friction material have been investigated. A sample is analysed with this method and chemical method, t test shows no significant difference in statistics. Therefore the method is not only simple and rapid but also accurate and reliable.
