QIAN Tian-cai, ZHOU Lie-xing, MOU Lei. The Structure of ZnO/AC Prepared from Spent Catalyst and Its Purification Properties for Air[J]. Journal of Materials Engineering, 2010, 0(3): 1-3,65.
The composite material,supported ZnO/activated carbon,were prepared from spent catalyst supported zinc acetate by microwave heating.The adsorption and catalytic property of the material have been studied for formaldehyde and TVOC,and the microscopic structural and surface properties of the material were analyzed by modern analysis instruments.The results show that the composite material has developed pore structure and then higher adsorption capacity for the volatile organic compounds in air,and the supported zinc oxide to be submit 6 square structures has higher catalytic property for the formaldehyde in air.
HUANG Hui-zhen, WEI Xiu-qin, SHUAI Ge-wang, ZHOU Lang. Study on the Properties of Sn-9Zn-xP Lead-free Solder Alloy[J]. Journal of Materials Engineering, 2010, 0(3): 4-7,12.
Effects of P addition on the properties of Sn-9Zn eutectic lead-free solder alloy have been studied.The results show that P could significantly improve the wettability of Sn-9Zn to Cu because P addition can decrease the content of oxygen in Sn-Zn alloy by the application of Secondary Ion Mass Spectrometry(SIMS) analysis.P addition enhances the creep strength of the Sn-9Zn bulk materials and the shear strength of Sn-9Zn/Cu joints,while decreases its ductility.No significant change in the interfacial structure of Sn-9Zn/Cu joints was observed by addition of P.The mechanisms were also discussed.
YU Jie, CHEN Jing-chao, ZHOU Xiao-long, YE Wei, ZOU Yu, LIU Fang-fang. Molecular Dynamics Simulation for Arc Erosion Morphology of AgSnO2 Materials[J]. Journal of Materials Engineering, 2010, 0(3): 8-12.
AgSnO2 electrical contact material molten pool was simulated by Molecular Dynamics in order to study the microscopic mechanism for the arc quenching.The result shows that the model can simulate the characteristic of molten pool effectively which were set according to the molten pool phase,and the material movement and existing state are the key factors for electrical erosion resistance.Arc quenching can be realized by increaseing the oxygen composition in AgSnO2 electrical contact material,and the oxygen occur resolution reaction and phase change.
LU Guo-feng, QIAO Sheng-ru, GONG Man-feng, HOU Jun-tao, JIAO Geng-sheng. Fabrication and Oxidation Behavior of C/Si-C-N Composite[J]. Journal of Materials Engineering, 2010, 0(3): 13-17.
Carbon fiber reinforced Si-C-N matrix composite(C/Si-C-N) with a pyrolytic carbon(PyC) interlayer was fabricated by chemical vapor infiltration processing.The oxidation behavior of C/Si-C-N were investigated in air using thermogravimetry.The influence of the processing temperature on oxidation resistance of the C/Si-C-N composites was discussed.The results indicate that the C/Si-C-N composites prepared at different temperature have different oxidation behavior.The mass loss of C/Si-C-N prepared at higher temperature always increases with the increase of temperature.The mass loss of C/Si-C-N prepared at lower temperature firstly increases,then decreases between 800-1000℃,subsequently increases,with the increase of temperature.The higher processing temperature leads to the higher oxidation resistance of C/Si-C-N composites below 900℃,but make the oxidation resistance decrease above 900℃.
JIANG Da-chuan, TAN Yi, DONG Wei, WANG Qiang, PENG Xu, LI Guo-bin. Effect of Beam Density of Electron Beam on Phosphorus Impurity in Metallurgical Grade Silicon[J]. Journal of Materials Engineering, 2010, 0(3): 18-21.
In order to evaluate the effect of dephosphorization in silicon during melting and solidification,three-group electron beam melting experiments with the same melting power but different time for extinguishing beam density were carried out.According to the distribution of the phosphorus content in the obtained ingot,the formulas for the estimation of the phosphorus content in silicon is developed and the removal rate of phosphorus is calculated to be over 80%.Phosphorus in silicon could be effectively removed by evaporation when the beam density is over 235mA.
WANG Jing, BAI Shu-xin, ZHANG Chang-rui. Effect of Precipitators on the Formation Process of La2Zr2O7 Powder[J]. Journal of Materials Engineering, 2010, 0(3): 22-24,88.
Single phase La2Zr2O7 powders were synthesized by co-precipitation method using ammonia and oxalate ammonium as precipitant agent,respectively.The process and crystallography characters of these precursors were studied by means of DSC-TGA and XRD.The results show that the hydrate precursor decomposes into amorphous composites of oxides between 400-750℃ followed by crystallization of these oxides.The single-phase La2Zr2O7 is formed just at 800℃ for 2.5h.And the oxalate precursor decomposes into mixture of amorphous oxides at 400-650℃;After 700℃,three reactions,such as the decomposition of La(OH)3,the crystallization of amorphous oxides and the solid state reaction between La2O3 and ZrO2,take place synchronously.The pure La2Zr2O7 from oxalate precursor is not achieved until calcined at 1450℃ for 2.5h.The essence of higher heating temperature for oxalate precursor is pockety La3+ and Zr4+.
SUN Jie, AN Cheng-qiang, TAN Yong. Effect of Chromium Content and Corrosion Resistance for Tinplate with Different Passivation Methods[J]. Journal of Materials Engineering, 2010, 0(3): 25-28,92.
The tests,which consisted of chemical analysis,X-ray Photoelectron Spectroscopy(XPS) and electrochemistry method,were carried out to investigate the corrosion resistance,chemical state of element chromium and the chromium content for tinplate using chemical and electrochemical passivation methods.It was shown that there existed Cr,O and Sn in the passivation film.The total chromium content obtained by electrochemical method was higher than that of the chemical method by the analysis of chemistry.The chemical value and the composition in chromate passivation film were different between chemical and cathode passivation.The composition of the chemical passivation film were Cr2O3 and Cr(OH)3,while the composition of the electrochemical passivation film were Cr2O3,Cr(OH)3 and Cr.The corrosion resistance of the passivation film obtained by electrochemistry method was better than that of the passivation film obtained by chemistry method.
CHENG Guang-ping, HE Yi-zhu. Ni-Al Intermetallic Coatings Prepared by Laser-cladding Synthesize with Ni-based Alloy and Al[J]. Journal of Materials Engineering, 2010, 0(3): 29-33,37.
Ni-Al intermetallic compound coatings were prepared on mild steel substrate by laser-cladding synthesize with mixed powders of Ni-based alloy and Al.The coatings microstructure and phase constitution were studied with SEM,EDX,TEM and XRD.The results show that the two-phase microstructure of the coating consists mainly of β-NiAl and γ′-Ni3Al,with a certain amount of Fe and Si are retained in both solution.β-NiAl are uniformity and staggered fine dendrites surrounded continuously by γ′-Ni3Al,which is beneficial to reduce the coating brittleness.Compact coats jointed metallurgically with the steel are obtained on 1.5kW powers,a few pores but no cracks are also found in the claddings.
XIONG Lei, MA Hong-yi, WANG Ru-min, LIANG Hong-bo, GUAN Jing. Study on Surface Modification of Nano-TiO2 Grafted with Hyperbranched Poly(amine-ester)[J]. Journal of Materials Engineering, 2010, 0(3): 34-37.
A new method to chemical modified the surface of nano-TiO2 was studied.Coupling agent KH550 was grafted onto the surface of nano-TiO2.TiO2-g-poly(amine-ester) nanocomposites were synthesized through one-spot polycondensation between AB2 monomer and TiO2-g-KH550.The results of FTIR,TG and TEM showed that the hyperbranched poly(amine-ester)(HBP) was grafted onto the surface of nano-TiO2 and the weight ratio of the hyperbranched polymer grafted on the surface reached 15%.Results indicated that nano-TiO2 grafted with hyperbranched poly(amine-ester) had better dispersion in the ethanol and chloroform than that of unmodified nano-TiO2.
YI Xiao-hong, FAN Zhan-guo, ZHANG Jing-lei, LI Feng-hua, TIAN Ang. Experimental Study of Preparation of TiO2 Porous Films on the Surface of TC4 Titanium Alloy by Anodic Oxidation[J]. Journal of Materials Engineering, 2010, 0(3): 38-41.
TiO2 porous films were prepared directly on the surface of TC4 titanium alloy by constant voltage anodic oxidation using sulfuric acid,TC4 and stainless steel plate as electrolyte,anode and cathode,respectively.The micro-morphology of the TiO2 porous films on the substrate was observed by SEM.Meanwhile,phase composition of the porous films on the titanium alloy substrate was determined by XRD.The effects of oxidation process parameters such as the voltage,the anodization time and the concentration of sulphuric acid on the phase composition of TiO2 porous films were investigated.The results showed that,oxide films of titanium alloy after anodic oxidation were heterogeneous TiO2 porous films with pore size ranging from 90nm to 240nm.The XRD analysis showed that the oxide films prepared with different oxidation process parameters were all consisted of annatase and rutile phases.In 0.5mol/L sulfuric acid electrolyte,the annatase and rutile TiO2 appeared when the voltage was higher than 100V or anodization time was longer than 5min,and with the voltage and time increasing the content of rutile TiO2 increased gradually.The annatase and rutile TiO2 appeared with 0.3mol/L sulfuric acid electrolyte at constant voltage(≥120V),and the content of rutile TiO2 increased at first and then decreased with the increasing concentration of sulfuric acid.
ZHAO Jian-hua, MA Wei, ZHANG Wen-da. Influence of Micro-arc Oxidation Ceramic Coating on Mould Material Properties of Al Alloy for Rapid Tooling[J]. Journal of Materials Engineering, 2010, 0(3): 42-45.
The surface modification of Al alloy for rapid tooling by Micro-arc Oxidation(MAO) technology was studied.According to the special demand of mould used in metal mold casting,thermal fatigue of MAO layer,and influence of MAO layer on filling capacity of molten metal have been studied.The conclusions obtained are: MAO layer coated on the surfaces of mold is favorable to mold-filling of molten metal and as the layer gets thicker,the flowing capability of molten metal becomes better.The thermal fatigue tests indicated that the thermal fatigue life of MAO layer is much longer than that of other layers.
YU Ping, ZHANG Jin-ling, XU Hong, ZHANG Chang-qiao. Study on Corrosion of ACSR Covered by Inhomogeneous Dark Coating Immerged in Simulated Ocean Environment for 5 Years[J]. Journal of Materials Engineering, 2010, 0(3): 46-50,55.
Test that ACSR(Aluminium Conductors(Cable) Steel-Reinforced) was eroded in the ocean environment was simulated.By corrosion test,XRD,XPS,electrochemical properties test(EIS,Tofel),and SEM,it can be concluded that ACSR covered by inhomogeneous black coating which produced in some industrial areas of North China during the hot,rainy season are same as normal ones and their electrochemical properties are essentially consistent,for compact corrosion products coating the former had corrosion inhibition effect.So this sort of corrosion affects only the appearance but not the application of products.The conclusion can provide the production and application with important reference value.
ZHAO Guo-xian, LU Xiang-hong, HAN Yong. Analysis of the Reason on Tubing Corrosion Failure[J]. Journal of Materials Engineering, 2010, 0(3): 51-55.
Varying degree of corrosion occurred in internal and outer wall of tubing string.Serious corrosion is found in some well deep.The results of chemical composition analysis,metallurgical structure test,SEM,EDS and XRD show that chemical composition and metallurgical structure of the tubing meet the API Spec 5CT standard requirement.Large corrosion products stack at the bottom of the pitting.Cl- enriches under the corrosion product layer.Corrosion product in internal wall are FeCO3,MgFe(CO3)2,FeO(OH),Mg3Ca(CO3)4 and Fe3O4,that in outer wall are FeCO3,MgFe(CO3)2,CaCO3 and FeO(OH).Internal wall are damaged by CO2 corrosion.Corrosive gas and medium come into the space between casing string and tubing string corrode outer wall of tubing.Tubing around 3279 meter is most hardly affected because it is at the temperature which CO2 corrosion is most seriously.Cl- enrichment is the important reason inducing local corrosion.
CHENG You-liang, LI Tie-hu, LI Feng-juan, ZHUANG Qiang, JING De-qi, ZHAO Ting-kai. Preparation of Mesocarbon Microbeads with Silicone Oil/Pitch Emulsion[J]. Journal of Materials Engineering, 2010, 0(3): 56-59.
Mesocarbon Microbeads(MCMB) were prepared by heat condensation in the retort with coal tar pitch and silicone oil as the dispersion and heat exchange medium.The influence of silicone oil on the preparation of MCMB was studied by SEM,laser particle size analyzer and XRD.The results showed that silicone oil content had an important influence on the formation of MCMB.After the addition of silicone oil,the spheres with uniform distribution and smooth surface had smaller diameter and better crystallite structure.At the same time,the yield of THFI and surface adhesion between spheres decreased.With increasing silicone oil content,the diameter and crystallite structure of the spheres were hardly changed.The spheres presented better dispersion and the yield increased,while some small particles attached to the surface of MCMB.When the ration of silicon oil/pitch was 3:1,MCMB with uniform size distribution and smooth surface were obtained.D50of MCMB was 0.82μm,and the yield of THFI was 8.2%.
ZHANG Chang-song, GUO Chen-jie, DANG Xin-an, YANG Li-jun. Research of(Na0.84K0.16)0.5Bi0.5TiO3 Lead-free Piezoelectric Textured Ceramics Prepared With Reactive-templated Grain Growth[J]. Journal of Materials Engineering, 2010, 0(3): 60-65.
Plated-like Bi4Ti3O12 template particles synthesized by NaCl-KCl molten salt process were fabricated.(Na0.84K0.16)0.5Bi0.5TiO3 lead-free piezoelectric textured ceramics was prepared by dry and wet tape-casting technique through RTGG method.Sintering behavior,textured factor,microstructure and electric properties of textured ceramics in different technique conditions were investigated.The results show that the sintering range of(Na0.84K0.16)0.5Bi0.5TiO3 lead-free piezoelectric textured ceramics is only 10-20℃,the dielectric properties,piezoelectric properties of textured ceramics show obvious anisotropy,the electrical properties perpendicular to tape-casting direction are better than those along with tape-casting direction,the microstrcture and electrical properties of textured ceramics,prepared in two tape-casting methods,showed the best anisotropy in 1150℃,the piezoelectric constant(d33)is 134pC/N.
LU Lu, WANG Fu-zhong, ZHU Guang-ya, WANG Zhao-xu. 3-D Thermo-mechanical Coupling Simulation of the Tube Forming Process in Mannesmann Mill[J]. Journal of Materials Engineering, 2010, 0(3): 66-69,73.
The finite element method(FEM) is used for simulation of piercing process of the tube in Mannesmann mill.The numerical model is described and takes into consideration for example thermal phenomena present in metal during forming.The simulation results visualize dynamic distributions of equivalent strains,equivalent strain rates and temperature,especially inside the workpiece.On the basis of the basic parameters,the phenomenon in the piercing process is analyzed.The model was verified by comparing the values of calculated force parameters of the piercing process and those measured in laboratory conditions.
GUO Jing-jing, HAO Hua-qiang, YANG Xiao-jiang, LIU Zeng-xun, WANG Shu-huan. Study on Temperature and Stress Behavior in FTSC Thin Slab Continuous Casting Mold[J]. Journal of Materials Engineering, 2010, 0(3): 70-73.
Based on the solidification process of SPHC steel in H2 mold,using element birth and death in ANSYS software which alters states of thin slab elements along with residence time in continuous casting mold,to simulate the thermal and mechanical states in 2D transient mode.Temperature and stress distributions of thin slab in different parts of H2 mold were obtained.This analytical work can provide theoretical bases for optimizing mold tape and improve the quality of product.
HU Ming, GAO-jing, YU Hai-cheng, CHEN Qiu-hua. Thermodynamic Analysis of In-situ Al2O3-TiCP/Al Composites by MC Technique[J]. Journal of Materials Engineering, 2010, 0(3): 74-78,83.
The in situ Al2O3-TiC p/Al composites were successfully fabricated by melting and casting technique in the Al-TiO2-C system.The thermodynamic mechanism of the composites was investigated by means of DSC and SEM and EDS and XRD techniques etal.The results showed that the ideal composites can be obtained by controlling and adjusting process parameters,avoiding to formation of Al3Ti and Al4C3.the chemical reactions were complicated in the Al-TiO2-Csystem.Little overdose aluminum caused that the displacement reaction occurred between Al and TiO2 with releasing much heat,and Al2O3 and free Ti were formed,then the active Ti combined with C and produced TiC;more overdose aluminum caused the thermit reaction happened between Al and TiO2,and was generated,then Al3Ti combined with C and produced TiC.With the overdose aluminum increasing,the initial reaction temperature between Al and TiO2 decreased.
HOU Feng, YIN Yu-xin, TAN Xin, ZHAO Lin. Fabrication TiO2 Nanowires by Electrochemical Anodization[J]. Journal of Materials Engineering, 2010, 0(3): 79-83.
Anodization of titanium in a fluorinated glycol and H2O electrolyte was investigated.The prepared anodic film had nanotube-array architecture with 0.9-36μm tube length.We discuss in details the influence of anodic voltage,anodic time and electrolyte composition on the structure of titania nanotubes.The result showed that TiO2 nanowires with a diameter of 20nm and a length up to several micron only can be synthesized in NH4F/glycol solution with a small amount of water(glycol:H2O=39:1),60V anodic voltage and 2h anodic time.The nanowires originated from the vertical splitting of anodically grown nanotubes.
XIE Jian-jun, HAN Xin-qiang, HE Xin-jian. Water Retention Capacity of Soil for High Absorbing Water Resin of PAAM[J]. Journal of Materials Engineering, 2010, 0(3): 84-88.
The effect of different mass of poly(acrylic acid-acrylamide) superabsorbent(PAAM) on water retention capacity of soil in tap water and 0.9%NaCl aqueous solution was investigated at different ratios of river sand/soil.The results have shown that the times of decreasing the water retention ratios by 30% relative to the comparative experiments(no PAAM) in tape water have prolonged for another 560 h,445h,360h and 350h for four different ratios of the river sand and soil: 10:0,5:5,3:7 and 0:10,when the using mass of PAAM is 5g per kg soil under the natural evaporation conditions.The equilibrium absorbencies of soil in tap water are increased by 4.5,2.6,2.2,1.6and 1.2 multiple for five different ratios of the river sand and soil: 10:0,7:3,5:5,3:7 and 0:10.When the critical using mass of the PAAM is 5g per kg soil,the granular structure of the soil can be improved obviously and the applying require can be satisfied.However,the absorbency of PAAM in 0.9% NaCl solution is greatly reduced and the increasing water retention capacities are small when PAAM is used in the areas of saline-alkali soil.And the PAAM is suit for use in the areas of the sandy soil while it is not suit for use in the areas of high saline-alkali soil.
DU Yan-ying, SHI Yu-sheng, WEI Qing-song, LIU Jin-hui. Simulation and Experiment of Cold Isostatic Pressing of Stainless Steel Powder[J]. Journal of Materials Engineering, 2010, 0(3): 89-92.
The relationship between pressure and density of stainless steel powder has been attained by Cold Isostatic Pressing experiments.It has been used to describe hardening property of material in simulation.To describe the compaction behaviour,the Cam-Clay model of ABAQUS/Standard finite element software has been used to simulate Cold Isostatic Pressing experiments.The results of experiment and prediction are compared that show a general good agreement which implies the parameters used in simulation are appropriate.Then a ball specimen formed by Selective Laser Sintering has been subject to Cold Isostatic Pressing that is also simulated.The results show that the deformation is uniform.The results of experiment and prediction show a general good agreement.And predicted density also accord with that of experiment.The simulation can not only give a useful direction to process of Cold Isostatic Pressing,but also supply important instruction to dimension design of complex-shape parts.
SHI Hua, LU Feng, XIONG Jia-jin, XU Yong-xiang, WANG Jing. Study on the Synthesis of N,N′-dihexyl p-phenylenediamine[J]. Journal of Materials Engineering, 2010, 0(3): 93-95.
With the method of straight N-alkylation process,N,N′-dihexyl p-phenylenediamine is prepared by the reaction between p-phenylenediamine and 1-hexyl bromide,which structure is proved by element analysis and NMR spectrum analysis.Although without nitrogen protection and catalysts,a high rate of production and high selectivity are also achieved.
ZENG Da-xin, CHEN Yu-Lian. Preparation of Carbon Nanotubes-Cu Composite Powder[J]. Journal of Materials Engineering, 2010, 0(3): 96-98.
Carbon nanotubes(CNTs) were synthesized by CVD method,and then were dispersed in CuSO4 solution with the help of sonication.Dehydration and reduction in hydrogen atmosphere were carried out to obtain CNT/Cu composite powders.The composite powders were characterized by using SEM,TEM and XRD.The results showed that CNTs were uniformly dispersed in the composite powder,and some combined with Cu nanoparticles or were covered with Cu.
