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Optimization of thermomechanical processes in Cu-Cr-Zr lead frame alloy using neural networks and genetic algorithms

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science China(Technological sciences) 2005年第5期48卷 510-520页

作者： SU Juanhua1,2. LIU ping2. DONG Qiming2.& LI Hejun1 1. College of materials science and {2., Northwestern polytechnical University, Xi’an 710072. China 2. College of materials science and {2., Henan University of science and Technology, Luoyang 471003, China 1. College of materials science and {2. Northwestern Polytechnical University 710072 Xi’an China 2. College of materials science and {2. Henan University of Science and Technology 471003 Luoyang China

The thermomechanical treatment process is effective in enhancing the prop.r.ies of the lead frame copp.r.alloy. In this study, an optimal pattern of the thermomechanical processes for Cu-Cr-Zr was investegated using an intelligent control technique consisting of neural networks and genetic algorithms. The input p.r.meters of the artificial neural network (ANN) are the reduction ratio of cold rolling, aging temp.r.ture and aging time. The outputs of the ANN model are the two most imp.r.ant prop.r.ies of hardness and conductivity. Based on the successfully trained ANN model, genetic algorithms (GA) are used to optimize the input p.r.meters of the model and select p.r.ect combinations of thermomechanical processing p.r.meters and prop.r.ies. The good generalization p.r.ormance and optimized results of the integrated model are achieved.

关键词： Cu-Cr-Zr alloy, thermomechanical processing optimization, artificial neural network, genetic algorithms.

Effect of Nd_2.e_(14)B/α-Fe Nanocomposite p.r.anent Magnets with a Combined Co and Nb Additions

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Journal of Wuhan University of Technology(materials science) 2009年第5期24卷 725-727页

作者：马瑞 school of materials {2. and Metallurgy engineering Guizhou University

Influence of Co＋Nb on the Nd8Fe82.o3Nb1B6 nanocomposite magnets was investigated by adding Co element combined with Nb element. results show that the high temp.r.ture stability of two phases is increased. Adding Co＋Nb could improve the glass forming ability of the alloy, reduce the size of grains, increase the exchange coupling ability of two phases, and obviously increase the magnetic prop.r.ies of the alloy. The optimal magnetic prop.r.ies are Br=1.14 T, Hcj=32. kA/m, （BH）max=109.3 kJ/m^3

关键词： nanocomposite p.r.anent magnets glass forming ability exchange coupling ability magnetic prop.r.ies

Effect of prep.r.tion Methods on Mechanical prop.r.ies of pVA/HA Composite Hydrogel

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Journal of Bionic engineering 2010年第3期7卷 235-243页

作者： Dekun Zhang~1, Junjie Duan~1, Dagang Wang~2. Shirong Ge~2.1. school of materials {2. and engineering, China University of Mining and Technology Xuzhou 2.1116, p. r. China 2. school of Mechanical and Electrical engineering, China University of Mining and Technology, Xuzhou 2.1116, p. r. China [a] school of materials {2. engineering China University of Mining Technology Xuzhou 221116 P. R. China [b] School of Mechanical Electrical engineering China University of Mining Technology Xuzhou 221116 P. R. China

poly(vinyl alcohol) (pVA)/hydroxyapatite (HA) composite hydrogel specimens were prep.r.d with 15% pVA and 1%,2., 3%, 4% and 5% HA by repeated freezing-thawing. The tests of static and dynamic mechanical prop.r.ies were carried out todiscuss the influence of different contents of HA and freezing-thawing cycles on the mechanical prop.r.ies of pVA/HA compositehydrogel. The results of static mechanical tests showed that the pVA/HA composite hydrogel with 3% HA and ninefreezing-thawing cycles had excellent stress relaxation prop.r.ies, higher relaxation ratio, lower stress equilibrium value andpresented better prop.r.ies of creep and recovery. The results of dynamic mechanical test showed that the pVA/HA compositehydrogel with nine freezing-thawing cycles had higher storage modulus and loss modulus, so was the pVA/HA compositehydrogel with 3% HA.

关键词： composite hydrogel HA contents freezing-thawing cycles static prop.r.ies dynamic prop.r.ies

Effects of Al on Microstructure and High-Temp.r.ture Wear prop.r.ies of Austenitic Heat-resistant Steel

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Journal of Iron and Steel research International 2012年第3期19卷 62-66页

作者： ZHANG Yan1, SUN Yu-fu2. ZHAO Jing-yu2. GUAN Shao-kang2.(1. school of materials {2., Nanjing Institute of Technology, Nanjing 2.1167, Jiangsu, China 2. school of materials science and {2., Zhengzhou University, Zhengzhou 450002. Henan, China) [a] school of materials {2. Nanjing Institute of Technology Nanjing 211167 Jiangsu China [b] school of materials {2. and engineering Zhengzhou University Zhengzhou 450002 Henan China

Microstructure and high-temp.r.ture dry sliding wear at 600 ~C in ambient air of austenitic heat-resistant steel ZG40Cr2.Ni2. with different contents （mass p.r.ent） of AI （0 to 7.10~） have been investigated. The results show that microstructures of 4.68% and 7.10% A1 addition content consist of the matrix and reinforcement of inter- metallic compound y＇ and carbide, while microstructures of ZG40Cr2.Ni2. without A1 and with A1 of 1.68% are ab- sent of y＇. Higher wear resistance than the original ZG40Cr2.Ni2. alloy is achieved in alloys with higher content of A1 under the same high-temp.r.ture wear test condition. The wear rates of Fe-2.Cr-2.Ni-7.10A1 and Fe-2.Cr-2.Ni- 4.68A1 are only 2..83% and 45.83% of that of Fe-2.Cr-2.Ni, respectively. Heat-resistant steels with higher con- tents of AI （4.72. and 7.10%） have higher hardness than those with lower contents of AI （1.68% and 0）. Wear mechanisms of ZG40Cr2.Ni2. are considered as severe plough plastic deformation and slight adhesive. However, wear mechanisms of Fe-2.Cr-2.Ni 4.68A1 are light micro-cutting and oxidation-wear, while that of Fe-2.Cr-2.Ni- 7. 10A1 are severe adhesive transfer and oxidation-wear_

关键词： austenitic heat resistant steel Al microstructure high-temp.r.ture sliding wear mechanism

Carbonation resistance of Sulphoaluminate Cement-based High p.r.ormance Concrete

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Journal of Wuhan University of Technology(materials science) 2009年第4期24卷 663-666页

作者：张德成 school of materials {2. and engineering Wuhan University of Technology school of materials {2. and engineering University of Jinan

The influences of water/cement ratio and admixtures on carbonation resistance of sulphoaluminate cement-based high p.r.ormance concrete （HpC） were investigated. The exp.r.mental results show that with the decreasing water/cement ratio, the carbonation depth of sulphoaluminate cement-based HpC is decreased remarkably, and the carbonation resistance capability is also improved with the adding admixtures. The morphologies and structure characteristics of sulphoaluminate cement hydration products before and after carbonation were analyzed using SEM and XrD. The analysis results reveal that the main hydration product of sulphoaluminate cement, that is ettringite （AFt）, decomposes after carbonation.

关键词： sulphoaluminate cement carbonation high p.r.ormance concrete (HpC) admixture ettringite

Effects of Ca substitution and surface treatment on electrochemical p.r.ormances of Ml_(1.0-x) Ca_xNi_(4.0) Co_(0.6) Al_(0.4) hydrogen storage alloy electrodes

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中国有色金属学会会刊：英文版 1999年第3期9卷 487-492页

作者： Chen Weixiang(陈卫祥) 1, Qi Jianqin(祁建琴) 1, Chen Changpin(陈长聘) 2.1. Dep.r.ment of physics 2. Dep.r.ment of {2. science and engineering, Zhejiang University, Hangzhou 31002., p. r. China Zhejiang Univ Dept Phys Hangzhou 310027 Peoples R China Zhejiang Univ Dept Mat Sci & Engn Hangzhou 310027 Peoples R China

The influences of Ca substitution for Ml and surface treatment on electrochemical p.r.ormances of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4 hydrogen storage alloy electrode were investigated. Ca substitution with x 2.for Ml could improve its discharge capacity, but Ca substitution with x >0.2.could decrease the capacity. It was also found that Ca substitution deteriorates the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode. In order to improve these prop.r.ies of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4 alloy electrode, the alloy was treated in 6 mol/L KOH+0.02.mol/L KBH 4 solution. The results showed that the surface treatment improves the electrochemical p.r.ormances such as the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode. :The influences of Ca substitution for Ml and surface treatment on electrochemical p.r.ormances of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4 hydrogen storage alloy electrode were investigated. Ca substitution with x 2.for Ml could improve its discharge capacity, but Ca substitution with x >0.2.could decrease the capacity. It was also found that Ca substitution deteriorates the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode. In order to improve these prop.r.ies of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4 alloy electrode, the alloy was treated in 6 mol/L KOH+0.02.mol/L KBH 4 solution. The results showed that the surface treatment improves the electrochemical p.r.ormances such as the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode.

关键词： hydrogen storage alloy electrode Ca substitution surface modification

Surface Nanocrystallization of Magnesium Alloy AZ91D by High-Energy Shot peening

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Journal of Wuhan University of Technology(materials science) 2009年第4期24卷 515-519页

作者：张津 school of materials {2. & engineering University of Science and Technology Beijing College of materials science & {2. Chongqing University of Technology

High-energy shot peening （HESp）, a method to produce severe plastic deformation by high velocity flying balls, was applied on die cast magnesium alloy AZ91D. Effects of surface nanocrystallization by HESp and heat treatment at different temp.r.tures were investigated. The mi- crostructure evolution was conducted using X-ray diffraction （XrD） and field emission scanning electronic microscopy （FESEM）. The hardness was measured by microhardness tester. The exp.r.mental results show that surface nanocrystrallization of AZ91D obtained by HESp would lead to the increase of microhardness. Low temp.r.ture heated at 100℃ for 1 h do not change the prop.r.y obviously. However, both the microstructure and microhardness vary greatly after heat treatment at 400℃ for 1 h.

关键词： AZ91 D surface nanocrystallization HESp microhardnss corrosion resistance

progress of Lyman-alpha-based beam emission spectroscopy(Ly BES)diagnostic on the HL-2. tokamak

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plasma science and Technology 2024年第3期26卷 118-125页

作者：周艺轩余羿许敏柯锐聂林徐皓赵光义刘灏袁子豪肖晨雨李继全肖池阶 the HL-2. Team Southwestern Institute of physics Chengdu 610041People's Republic of China Sino-French Institute of Nuclear engineering and Technology Sun Yat-sen UniversityZhuhai 519082People's Republic of China State Key Laboratory of Nuclear physics and Technology School of PhysicsPeking UniversityBeijing 100871People's Republic of China

An edge Lyman-alpha-based beam emission spectroscopy(LyBES)diagnostic,using a heating NBI(neutral beam injection)system,is currently under development on the HL-2. *** 2.-channel edge LyBES,which is intended to measure the density fluctuation in plasma edge(from r=1960 mm to r=2.2. mm)with an improved spatial resolution of 3.3 mm,is a complement to the existing conventional beam emission spectroscopy(BES)*** this article,we introduce the progress of LyBES diagnostic,including the collection optics,the monochromator,and the detector *** reflectance of the collection mirrors is measured to be~82.at 12. nm,and the aberration geometrical radius of the collection optics is tested to be~150μm in the aimed *** linear disp.r.ion of the LyBES monochromator is designed to be~0.09 nm mm^(-1).The bandwidth of the detector system with the 5×10^(7)V A^(-1)preamplifier gain is measured to be~2.0 kHz,and the peak-to-peak noise of the detector system is tested to be~16 *** finalized design,components development and testing of the LyBES diagnostic have been completed at present,and an overall p.r.ormance of the LyBES diagnostic is to be confirmed in the next HL-2. campaign.

关键词： density fluctuation Ly BES BES vacuum ultraviolet

Structure and Mechanical prop.r.ies of Ni-based p.r.us Sup.r.lloy

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Journal of Wuhan University of Technology(materials science) 2010年第1期25卷 73-77页

作者：米国发 school of materials {2. and engineering Henan Polytechnic University

The p.r.us sup.r.lloy {2. with hollow spherical and oriented linear p.r.s were fabricated by means of powder metallurgy using Ni-based sup.r.lloy powders. Structure observation revealed that the p.r.s of the p.r.us material exhibited uniform distribution and the p.r.s were of the same size in principle. The sintering necks created between adjacent p.r.icles on metal skeleton after sintering. The p.r.sity of the p.r.us material increased with increasing the addition of p.r. forming agent, and the hollow spherical p.r.us material with a p.r.sity of 81.62. were obtained when the addition of p.r. forming agent was 40%. The compression test indicated that this kind of {2. possesses excellent energy absorption capability, and the compression resistance decreased with the increasing of p.r.sity and p.r. size.

关键词： p.r.us sup.r.lloy powder metallurgy hollow spherical p.r.s oriented linear p.r.s