R. E. Salin, E. N. Kablov, V. V. Gerassimov. Semicontinuous Vaccum Device Type of YBHK-8П For Directional Solidification[J]. Journal of Materials Engineering, 1992, 0(2): 4-5.
In this paper the directional solidification process of blades in gas turbine engine of former Sovit Union and the special device used for the process are described. The device is a complex synthetic body of energies, in which vaccum system, water-cooling system and autocontrol system of vaccum and temperature at a series of points are installed. The device can ue used for manufacturing blades with colum or single crystal structures at the velocity of solidification 10~20 mm/min by comparison with the general directional solidification velosity of 2~4 mm/min.
Gao Wen, Han Yafang, Li Sunhua, Wang Yumin. TEM Observation of Deformation Microstructure of Ni3Al Base Superalloy at Different Temperatures[J]. Journal of Materials Engineering, 1992, 0(2): 6-9.
The microstructure and dislocation configurations of Ni3Al base superalloy specimens of primary condittion, short time tension at room temperature and 870℃ > protracted creep at 1100℃ were observed by means of TEM. It was showed that there was a mount of mismatching dislocation network at the Y/Y’interface, and these dislocations played a great hindrance role in dislocation movement in deformed Y’matrix. In the process of protracted creep at 1100℃ microstructure of the alloy changed distinctively into circular structure of high dislocation density because of the Y phase coalescence and resolution, it still had a strengthening effect to the alloy. Y phase was the strengthening phase of the alloy.
Ye Wujun, Zang Wei, Ding Chuanfu, Zao Zenye. Study on Spectrum Load Fatigue Behaviors, Fracture Mechanism and Fractography of Two Ultra-High Strengh Steels[J]. Journal of Materials Engineering, 1992, 0(2): 10-14.
Spectrum fatigue behaviors of two ultra-high strength steels are compared and the mechanism of initiation and propagation of fatigue crack is observed. Test results show that the fatigue life of 300M steel with isothermal heat treatment is 1.2 times that of 30CrMnSiNi2A steel. In the initiation period, fatigue crack propagation is under mechanism of striation, and in the middle, is under small plane cleavage and striation. The relation between second crack and martensite bunch is also discussed.
Yan Dajing. Analysis about Strengthening Mechanism from the Ageing Process of 7475 Al Alloy[J]. Journal of Materials Engineering, 1992, 0(2): 15-17,5.
The change law about microstructures and mechanical properties of 7475 Al alloy during its ageing process at the temperatures of 110~140℃ was investigated. By the observation and the calculation of activation energy of precipitates, the size, distribution,, shape and type of the precipitates in various temperatures and periods, as well as their effects on the alloy’s strength have been determined.
Zhang Zhifang, Zhang Chunsheng, Cai Wei, Zhao Liancheng, Luo Wanchun. Structure and Properties of Ni-Ti-Nb Wide Retardation Memory Alloy in Aviation Industry[J]. Journal of Materials Engineering, 1992, 0(2): 18-20.
The phase transformation retardation of martensite, mechanical properties and charateritical strain reinstatement of Ni47-Ti44Nbg alloy are studied by means of transmission electron microscope and electronic tensile test, and its application in aviation industry is discussed also.
Bi Jing, Ma Zongyi, Shen Hongwei, Lu Yuxiong, Gao Yinxuan. Effects of SiC Size and Content on the Properties of SiCp/2024Al Composite[J]. Journal of Materials Engineering, 1992, 0(2): 21-23.
The properties of SiCp/2024Al composite fabricated by powder metallurgy technique were investigated. It is found that with increasing SiC particulate size the strength of the composite decreases, and the elongation and abrasive wear resistance increase. SiC particulate size has no effect on the physical properties of the composite. With increasing SiC particulate content, the strength, modulus and abrasive wear resistance of the composite increase, and the elongation and coefficient of thermal expansion decrease.
Zhang Shaoqing. Effect of Hydrogen on Hot Processing of Titanium Alloys[J]. Journal of Materials Engineering, 1992, 0(2): 24-29,40.
The new research directions of the improvement in properties and workabilities for metals and alloys by hydrogenation were reviewed, especially the improvement in hot workabilities for titanium alloys, and the results of studies on hydrogen induced superplasticity of titanium alloys by the author were reported.
Lu Souping, SunJisheng, Liu Xiaofang. Effects of Technological Factors of Wide Clearance Brazing on Formation and Microstructure of Joints[J]. Journal of Materials Engineering, 1992, 0(2): 30-33.
The effects of technological factors of wide clearance brazing, on formation and microstructure of jointsare investigated in this paper. It is found that the joints of stable high quality can be obtained by themetal fines preset type with suitable proportion. The formation mechanism of wide clearance brazing is discussed.
Liu Dejun, Yu Feng, Wang Jiegan. Oxidation Resistance of Steel 1Cr18Ni9Ti with TiN Film Ion-Plated[J]. Journal of Materials Engineering, 1992, 0(2): 34-36.
The high temperature oxidation resistance of austenite stainless steel 1Cr18Ni9Ti with TiN surface film ion-plated is studied. The results show that the weight gain of the specimen with TiN film 4.5μm thick decreases by 90% and 73% after 104 hours at temperature 850℃and 950℃ respectively.
Guo Yajun. Dynamic Response and Stress Analysis of Composite Laminates Subjected to Impacting[J]. Journal of Materials Engineering, 1992, 0(2): 37-40.
Dynamic response and stress history of fiberite T300/934 graphite/epoxy composite laminates subjected to low-velocity, non-penetrating impact were analyzed with linear-elastic, transient finite element method. Three-dimensional finite element codes, by the name of "IMPACT", which was written with standard FORTRAN on VAX/750, can calculate the displacements of laminate and impactor, the contact force between impactor and laminate and the stress of laminate. With "IMPACT" codes, the responses of T300/934 laminates, impacted by steel ball with several kinds of velocities were evaluated. The effects of ply-angle, ply-sequence of laminates and velocity of impactor on the deflection and contact force of laminate were discussed.
Gao Yuankun. Relationship between Surface C Content and Properties of Carburized Steel Components[J]. Journal of Materials Engineering, 1992, 0(2): 52-54.
In this paper the effects of surface C content and Concentration distribution on the properties of carburized steel components, such as hardness, wear resistance, bending, torsion, impact strength and fatigue resistance, are described, and the optimium value of C content is presented. For this purpose, the control of furnace gas carbon potential and real time simulation processing of C concentration distribution must be made using computer.
