1997 Vol. 4, No. 3

Display Method:
New formulae for calculating activities from binary system phase diagrams containing solid solution by introducing the parameter θ
ZHANG Fan, XIE Fanyou, CAI Wenjuan, and  CHOU Kuochih
1997, vol. 4, no. 3, pp. 1-4.
Abstract:
New formulae for calculating activities and activity coefficients from binary phase diagrams containing solid solution are presented. In the new formulae, a parameter θ is introduced. It seems be more efficient The application of these formulae to system Ag-Pb proves its efficiency.
A probable new phase H(Ni2Ti9Si9) in Ti-Ni-Si ternary system at 1100 ℃
HU Xiaohua, CHEN Guoliang, and  NI Kequan
1997, vol. 4, no. 3, pp. 5-7.
Abstract:
A probable new phase was detected in Ni-Ti-Si temary system at 1 100 ℃. Its composition is around Ni:Ti:Si = 10:45:45 (atom fraction) according to the results of EPMA (Electron Probe Microanalysis) of 4 alloy scontaining the Phase. The SEM microstructure difference of the 4 alloys can give some proof of its existence.
Microstructures of laser cladding of intermetallic-ceramic composite coatings
ZHOU Xianglin, CHEN Chuanzhong, CHANG Chun, YU Jiahong, and  HU Hanqi
1997, vol. 4, no. 3, pp. 8-10.
Abstract:
The microstructures of laser cladding of (Ni-24.5%(atom fraction)Al)+50%(mass haction)WC coatings before and after aging was comparetively studied by using SEM and TEM. It is shown that dissolving of WC and reprecipitating in the forms of WC and W2C occurred during laser cladding, and intermetallic γ' (Ni3Al) orderly precipitate from metastable supersaturant Ni-matrix solid solution after heat treatment. The structures are favorable for coating's properties.
Nanocrystalline exchange-coupled Pr-Fe-B permanent magnets
WANG Zuocheng, ZHANG Maocai, QIAO Yi, GAO Xuexum, LI Fubiao, ZHOU Shouzeng, and  WANG Run
1997, vol. 4, no. 3, pp. 11-13.
Abstract:
Nanocomposite Pr2Fe14B/α-Fe permanent magnets were prepared by melt spinning and subsequent crystallizahon of Pr8Fe86B6, amorphous Precursnors. The microstructure is a two-phase nanocomposite of Pr2Fe14B and soft magnetic α-Fe with an average size of 30nm. X-ray diffration, Thermomagnetic analysis and TEM analysis indicate that amorphous Pr8Fe86B6, alloy crystallizes through the process of Am→Am'+α-Fe→Pr2Fe23B3+α-Fe-Pr2Fe14B+α-Fe. The highest value of remanence (Br), cocreivity (Hci) and maximum energy Product ((BH)max) of the nanocrystalline alloys are 1.10T, 340 kA/m and 110 kJ/m3 respechvely, exhibihng remarkable remanence enhancement. The effect of annaling temperature and time on the microstructure and magnetic properties was also studied. The results show that appropriate annealing temperature and time are important for obtaining the optimal microstructure and the bestmagnetic properties.
A new composite: spray-deposited M2 high speed steel reinforced by WC particles
ZHANG Liying, TIAN Haige, HUANG Thuo, and  WU Chengyi
1997, vol. 4, no. 3, pp. 14-17.
Abstract:
The fabrication of the high speed steel matrix composites reinforced by WC particles utilizing the ultrasonic gas atomization and spray-deposition was studied. The change of microstware and mechanical Properties of the composites added WC Particles were investigated and analyzed as well. As some results, the WC particles exhibit two morphologies (spherical and angular) with different content of WC particles; and with the increase of content of WC particles, the hardness of the composites increases, yet the bending strength appears a trend of decreasing.
Fretting corrosion of surgical 316L stainless steel in saline solutions
BAI Zhijun, WU Yinshun, ZHANG Tiancheng, and  LIU Qiang
1997, vol. 4, no. 3, pp. 18-21.
Abstract:
A new simulation system for the laboratory investigation of fretting wear is developed. It consist of a mechanism device, a electrochemical cell and a datum acqulsition and process software. Fretting of surgical 316L stainless steel in saline is studied. The results show that electrochemical corrosion is enhanced by fretting and anodic current density under fretting is 100 times than static condition. Fretting corrosion is a mechanic -elec trochemical al Process.
Mechanism of liquid zinc corrosion on metals
CAO Xiaoming, LONG Yi, and  WANG Run
1997, vol. 4, no. 3, pp. 22-26.
Abstract:
Two kinds of materials, soluble and insoluble in liquid zinc, such as Fe and FeB, are separately dealt with. A new theory is presented for insoluble materials. Based on the theory, the surface defects of insoluble materials are the main reason that the matcrials are correded.
Influence of texture pretreatment on cold rolling texture of ELC-BH sheet
GUAN Xiaojun, ZHOU Jiajuan, HU Xiaojun, and  WU Qiulin
1997, vol. 4, no. 3, pp. 27-29.
Abstract:
In order to further investigate how cold rolling texture is produced in an extra low-carbon and high strength bake-hardening sheet steel (for short, hereafter, coiled ELC-BH sheet) with r value as high as 2.67, texture change in texture pretreatment and its effects on the cold rolling texture are researched by means of Orientation Distribution Funchon (ODf) method. Experimental results show that the cold rolling texture which Produces very strong {111} annealing texture actually is caused by texture change in the texture pretreatment, and the strong {111} texture obtained rough this texture pretreatment is an essential condition of engendering the cold rolling texture, while the stability of {111} texture components in cold rolling is a sufficient condition of emerging thes one.
Temperature distribution in the tool-chip-workpiece system during the orthogonal cutting process
ZHENG Chun and  GU Tong
1997, vol. 4, no. 3, pp. 30-34.
Abstract:
The temperature distribution in the tool, chip and workpiece was studied during the orthogonal cutting process Under several different cutting conditions. The temperature distribution is calculated by the finite difference method. and the variation of the material properties with temperature was taken was taken into account The results obtained are coincident with both previous published results and experimental measurements.
Residual stress around rail bolt holes after cold-expansion
SHEN Hongwei, SUN Ning, MU Ensheng, and  ZOU Dingqiang
1997, vol. 4, no. 3, pp. 35-42.
Abstract:
Focused on rail bolt hole cold-expansion, the theoretical prediction models and results of residual stress analysis on related Problems are summarized. And a stress analyzing method based on both of the strain measurement during the Process of cold expansion and elastoc-plastic theory is developed. By the method proposed and the magneto-elastic method as well as the stress relief measurement detailed experimental study on the residual stress surrounding the cold-expanded tail bolt hole is performed. Relationship between the distribution of residual stress and cold expansion rate are established. The adaptability and limitation of theoretical predichon are also analyzed by comparing the theoreticaland experimental results.
Application of intelligent control theory in AC servo system
WANG Zhiliang, XIE Lun, and  LI Chongjian
1997, vol. 4, no. 3, pp. 43-45.
Abstract:
An AC servo system based on neuron control theory is presented. Experimental results show that the neural control mode doesn't need the Precise model of the system, therefore, it has many advantages, such as simple design and high response performance. The simulation research of the AC servo system which is non-linear, time-varied.based on neuro-fuzzy controller is done. The results of the simulation show that the performances of the system are considerably improved and it is one of the novel pathways to realize intelligent control of servo system.
Short-term load forecasting based on fuzzy neural network
DONG Liang and  MU Zhichun
1997, vol. 4, no. 3, pp. 46-48,53.
Abstract:
The fuzzy neural network is applied to the short-term load forecasting. The fuzzy rules and fuzzy membership functions of the network are obtained through fuzzy neural network learming. Three inference algorithms, i.e. the multiplicative inference, the maximum inference and the minimum inference, are used for comparison. The learning algorithms corresponding to the inference methods are derived from back-propagation algorithm. To validate the fuzzy neural network model, the network is used to Predict short-term load by compaing the network output against the real load data from a local power system supplying electricity to a large steel manufacturer. The experimental results are satisfactory.
Wavelet analysis and its application to signal processing
HE Jun and  WU Yalun
1997, vol. 4, no. 3, pp. 49-53.
Abstract:
The construction of basic wavelet was discussed and many basic analyzing wavelets was compared. A complex analyzing wavelet which is continuous, smoothing, orthogonal and exponential decreasing was presented, and it was used to decompose two blasting seismic signals with the continuous wavelet transforms (CWT). The result shows that wavelet analysis is the better method to help us determine the essential factors which create damage effects than Fourier analysis.
Interactive graphics mechanical optimum design
WANG Guobiao
1997, vol. 4, no. 3, pp. 54-56.
Abstract:
Virtually all conventional optimizations are Performed in a batch computer environment. No graphic information during the optimization process is provided. The research tactics and implementation procedure of interactive graphics in mechanical optimum design are presented. An interactive Graphics Mechanical Optimum Design Program(IGMODP) for microcomputers is developed. The example of wheeled loader's working device optimum design using IGMODP is carried out.