bluuebunny/crossref_metadata_2025 huggingface dataset:
On the Experimental Methods for the Determination of Elastic Modulus and Hardness of Cement Particles by Nanoindentation
Authors: Liang Kang , Yao Wu , Song Dan , He Li
Published: December 2010

The elastic modulus (E) and hardness (H) of the cement particles that embedded in different subbases (namely epoxy resin and hardened cement pastes with different ages) were measured by nanoindentation. The results indicate that the measured values of E and H of the cement particles encased in resins are smaller than normal values, while the measured values of cement particles embedded in hardened cement pastes are closely related to the hydration degree of subbase cement pastes. As nanoindentation measurement of cement particles is significantly affected by the hardness of the subbase, the test of E and H of cement particles should be carried out based upon a rather hard substrate.
Bond Behaviour of Concrete Block Including Steel Mesh of Various Rib Pattern and Bar Size
Authors: Yang Jian , Du Qiang , Bao Yi Wang
Published: December 2010

Bond behavior plays an important role in developing load carrying capacity and ductility for concrete structures. Studies on bond behavior of single bars have been extensively conducted and whereas those on steel meshes are rather limited. This paper reports an experimental study on the bond behavior of concrete blocks with steel meshes. By varying the rib pattern and bar size of the steel mesh, their influence was examined.
Testing Methods of Adiabatic Temperature Rise in Concrete
Authors: Wang Jun , Ma Bao Guo , Wu Xiong , Yang Wen , Zhao Ri Xu
Published: December 2010

The existing testing methods of adiabatic temperature rise in concrete were compared and analyzed in this article, the advantages and disadvantages were found out among every testing methods, and a testing device was designed and developed on the basic. By comparing the experimental findings, the developed equipment, which is simple, convenient, and more accurate response to changes of the actual temperature in concrete, had better value of use and promotion.
Microstructure and Properties of Metal-Ceramic Composite Coating by Laser Surface Alloying on 9CrSi Steel
Authors: Wang Wen Yan , Dong Xiao Ming , Xie Jing Pei , Xu Jing , Li Luo Li
Published: December 2010

Using sub-micron WC/Co metal ceramic composite as coating materials for laser alloying experiments to prepare high hardness and wear resistance alloyed layer on the surface of 9CrSi. The microstructures of laser-alloyed coating were detected by SEM and XRD. The microhardness and wear-resistance of the coatings were also investigated. The results indicate that, the laser alloyed layer and substrate form a good metallurgical bonding. The analysis of SEM reveal that the alloyed layer can be divided into alloyed zone, heat affected zone and substrate zone. The alloyed zone is composed by martensite, netted dendrite carbides and small carbide particles, the netted dendrite carbides distribute in the martensitic and the small carbide particles dispersed in the gap of the netted dendrite. The heat affected zone is consisted of retained austenite and martensite. There is no significant change in the matrix zone.The coating has a high hardness of 900HV0.2 , and the abrasion loss of the alloyed coating is just one ninth of that of 9CrSi. The wear resisitance of the alloyed coating relative to the substrate 9CrSi has significantly improved.
Effect of Nitrogen Pressure on the Morphology of Combustion Synthesized β-Si3N4 Crystals
Authors: Li Wen Kui , Zhuang Han Rui
Published: December 2010

This paper presents the results of synthesizing rod-like -Si3N4 crystals with Y2O3 as additives by combustion synthesis under different nitrogen pressure. The effect of nitrogen pressure on the final morphology of rod-like -Si3N4 was investigated and the crystal growth mechanism was discussed in detail. The results reveal that the final morphology of products is depended on the nitrogen pressure. With the increasing nitrogen pressure, the ratio of rod-like crystals is increasing.
Synthesis, Structure and Properties of Super Fine LiMn2O4
Authors: Song Jie , Xu Bing , Huang De Xin , Li Cai Xia , Li Qiang
Published: December 2010

In this paper, super fine LiMn2O4 powder was synthesized by mechanochemical method starting from Li2CO3 and Mn2O3. The structure, size and morphology of LiMn2O4 were explored with X-ray diffraction and scanning electron microscopy (SEM). The electrochemical properties of LiMn2O4 were studied in 2 mol/L (NH4)2SO4 solution. The result showed that pure spinel LiMn204 powder was prepared after 8h grinding with 3.0KW of power and the particle size was about 1µm. Cyclic vohammetry curve indicate LiMn2O4 electrode material has better capacitive performances.
Effects of Heat Treatment on Crystal Structure and Reactivity of Sericite
Authors: Xu Xia , Ding Hao , Liang Ning , Wang Yue Bo , Yan Wei
Published: December 2010

To activate the reactivity of sericite and make it have the abilities of ion exchange and intercalation between layers, the effects of heat treatment on crystal structure and reactivity of sericite were studied. The results, analyzed by XRD and Hall formula, indicate that sericite still retains its crystal characteristics after being activated by heat treatment at 500°C-800°C, but there are significant lattice distortions, and the maximum one occurred at 800°C. It can be seen from the SEM images that heat treatment reduces the order of sheets of sericite and makes the surfaces rough and the edges and corners smooth. The Al3+ dissolution amount from the sericite in HNO3 is 24.34 mg/g after heat treatment, which is increased significantly compared with the untreated one. It demonstrates that the reactivity of sericite is improved remarkably.
Nonstoichiometric Lithium Iron Phosphate Synthesized by Hydrothermal Route
Authors: Ou Xiu Qin , Liang Guang Chuan , Wang Li , Song Qing Zhu , Wang Zuo Rui
Published: December 2010

Lithium iron phosphate with varied Fe/P molar ratio was synthesized from LiOH, FeSO4, and H3PO4by hydrothermal route at 180°C for 6 h. The samples were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), chemical analysis, and constant current charge-discharge cycling test. It was found that at the same pH value of reaction, the Fe/P ratio had a major effect on the content of impurity phase, crystal structure and electrochemical performance of the samples. However, it had a minor effect on the morphology of the samples. A single phase structure was obtained for the samples with the Fe/P ratio of 0.97-1.02. The sample with the Fe/P ratio of 0.97 exhibited the best electrochemical behaviors, whose specific discharge capacities could reach 152.7, 144.8 and 133.2mAhg-1at 0.2C, 1C and 5C rate, respectively, with the capacity retention rate close to 100% after 50 cycles at 5C. It is believed that the excellent electrochemical performance of specific discharge capacity, rate capability and cycling stability is attributed to the nonstoichiometry of LiFePO4, which results in the Li-rich defective crystal structure and the decrease of cell parameters, thus facilitating the discharge behaviors at high rates.
Preparation and Characterization of La0.9Sr0.1Co0.5Mn0.5O3 Composite Catalytic Materials for Conversion of Exhaust Gas from Natural Gas Automobiles
Authors: Zhang Xue Fang , Xue Gang , Liang Jin Sheng , Zhang Lei
Published: December 2010

A series of rare earth perovskite-type oxides La0.9Sr0.1CoO3, La0.9Sr0.1MnO3 and La0.9Sr0.1Co0.5Mn0.5O3 were prepared by sol-gel method and characterized by X-ray diffraction (XRD), specific surface analysis (BET), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) techniques. The results showed that for La0.9Sr0.1Co0.5Mn0.5O3 sample, Sr2+ and Mn3+ ions partly replaced La3+ and Co3+ ions and entered perovskite crystal lattice, and finally a perfect crystal structure of perovskite was formed. Moreover, these powders presented sphericity granules with particle size of about 20nm and satisfactory pore structure. With the doping of Sr2+ ions in a certain range, the coexisting system of Mn3+- Mn4+ and Co3+- Co4+ as well as the concentration of oxygen vacancies were increased, thus leading to the higher catalytic activity of the prepared catalysts.
Reaction Mechanism of LiFePO4/C Cathode Materials Synthesized by Carbothermal Reduction Method
Authors: Gao Li Min , Liang Guang Chuan , Wang Li , Zhi Xiao Ke , Jie Xiao Fei
Published: December 2010

LiFePO4/C powders were synthesized by carbothermal reduction method using Li2CO3 (A.R), FePO4 (A.R) and glucose as raw materials. In this paper, the carbothermal reaction courses were characterized by Thermo-gravimetric (TG)/Differential Thermal Analysis (DTA), X-ray diffraction (XRD) and Fourier transform infrared (FTIR). It was found that the different synthesis temperatures and the different reducing atmosphere in systems could lead to different reactions, resulting in different final products and a direct impact on material performance. At around 350 °C LiFePO4 is directly formed without intermediate phase. In lower temperature of 400-500 °C, the sample included a certain amount of Li3PO4 and Fe2O3 impurity phases. When calcination temperature rose to 550 °C, the sample could be pure LiFePO4 phase.
Synergistic Effects of Zinc Oxide on Intumescent Flame-Retarded Polypropylene Composites
Authors: Hu Shan , Zheng Hui , Shen Shang Yue , Han Hong Chang , Jing Hui , Li Shuo
Published: December 2010

The melamine phosphate (MP) was synthesized from melamine and phosphate acid. Zinc oxide (ZnO) was used as a synergistic agent by adding into the MP during the synthesis process. The reaction products were characterized by Fourier transform infrared spectroscopy (FTIR). The properties of polypropylene (PP) composites containing intumescent flame retardant (IFR) additives of melamine phosphate and pentaerythritol (PER) were investigated by the limiting oxygen index (LOI), UL-94 vertical burning test, thermogravimetric analysis (TG) and scanning electron microscopy (SEM). The results indicated that the LOI value of the composites could be enhanced obviously with suitable content of ZnO. When the ZnO content was 6 wt% in MP, the LOI value reached 34.1%, which showed 10% higher than that of the composites without ZnO.
Synthesis of Ordered Lamellar Nanostructured Zirconia via SDS Template
Authors: Zhao Shan Shan , Liu Chao , Ji Xiu Jie , Li Song , Ma Dong Xia
Published: December 2010

The ordered lamellar nanostructured zirconias were prepared via atmospheric reflux and hydrothermal hybrid method in ethanol-water system by using zirconium oxychloride as zirconium source and sodium dodecyl sulfonate (SDS) as template agent, which were characterized by X-ray diffraction (XRD). The results showed that the ordered lamellar nanostructured zirconias were composed of tetragonal phase for 110 and 125°C and tetragonal/monoclinic phase for 140 and 155°C. As the hydrothermal temperature raised, the monoclinic phase began to appear, and the crystallization is promoted, but the ordered lamellar nanostructure was shrinking prior to expanding in size, ranged from 1.33 to 1.55 nm, and tended to decrease in amount gradually. For the sample prepared at 110°C, the Fourier-transform infrared spectroscopy (FT-IR) pattern demonstrated that the inorganic phase is tetragonal zirconia and there remain small amount of template SDS. And the calcined lamellar nanostructure with a 1.2 nm periodicity was observed by transmission electron microscopy (TEM). This indicates the lamellar structure shrunk from 1.51 to 1.2 nm and was preserved after calcination at 500°C, showing good thermal stability.
Thermal Insulation Coatings Containing Sepiolite Mineral Fibers and their Performance
Authors: Chen Cong , Wang Fei , Liang Jin Sheng , Tang Qing Guo
Published: December 2010

In this text, the effective thermal conductivity of different shape filler particles was investigated. The thermal insulation coatings were prepared using hollow glass beads and sepiolite as thermal insulation fillers and the thermal insulation effect was evaluated. The results show that the optimum ratio of sepiolite and hollow glass beads is 6:1, and the temperature difference of upper box and lower box is up to 18 °C. The main reason for this phenomenon is that the thermal conduction chain is difficult to form in the direction of heat flow, thus leading to the increase of thermal resistance and decrease of thermal conductivity.
Object Detection Based on Visual Selective Attention Mechanism
Authors: Sun Jian Zhong , Liu En Hai , Li Cui Bin
Published: December 2010

Visual selective attention modeling is an advanced topic in cognitive information perception. According to human visual perception theory, which is based on the introduction of the representative visual attention model (Itti model), in its initial stages of feature extraction, in order to form a new guidance note of the saliency map, new low-level visual features are introduced, which achieves a more accurate target detection. The results prove that this method can avoid the leakage detection to some extent, which makes attention regional more close to the actuality of biological visual system.
Cultivation and Practice of Engineering Masters’ Innovative Ability
Authors: Tang Qing Guo , Liang Jin Sheng , Wang Qun Ying , Wang Fei
Published: December 2010

Knowledge is material foundation of innovation, and awareness is spiritual power and soul of innovation. The cultivation of innovative ability is not only to pass on knowledge by suitable approaches and correct teaching methods, but also to stimulate students’ enthusiasm of seeking knowledge and discover their wisdom potential. In the teaching process, in order to cultivate students’ unique innovative ability, creating suitable atmosphere for innovating and developing students’ sense of social responsibility and scientific dauntless spirit are needed. Furthermore, with the social demand and longing for success as the force, mobilizing the students’ subjective initiative fully is important. In the innovative practice, discovering students’ mental function, stimulating their imagination and innovative awareness should also be taken into account.
Effect of Attapulgite and Carbon Black on the Properties of Natural Rubber
Authors: Yang Mei , Hu Sheng , Shen Shang Yue , Li Tie
Published: December 2010

The modified attapulgite / natural rubber composites (MANRC), attapulgite / natural rubber composites (ANRC) and carbon black N330 / natural rubber composites (CBNRC) were prepared by co-coagulating rubber latex and clay aqueous suspension,respectively. The modified attapulgite was attained by dispersion with an ultrasonic cell pulverizer first and then modification with cetyltrimethylammonium bromide (CTAB). The micrographs of field emission scanning electron microscope (FESEM) and environmental scanning electron microscope (ESEM) showed that the CTAB-modified attapulgite have the best dispersibility in the composites. The mechanical properties of MANRC are the best. The best properties of MANRC can be obtained when 20phrCTAB-modified attapulgite was added, the tensile strength, the 200% tensile modulus, the tear strength and Shore A hardness increased by 58.2%, 109.3%, 46.0%, 27.8%, respectively, compared with CBNRC.
Effect of Mineral Composite Fillers on Properties of Man-Made Plywood
Authors: Shao Hong Xia , Tang Qing Guo , Liang Jin Sheng , Ding Yan
Published: December 2010

Attapulgite mineral powder as raw material, through surface modification and composite of various mineral processing, the effect of modifier dosage, composite powder filler ratio on the mechanical properties and formaldehyde emission of the plywood which is bonded by filled urea-formaldehyde resin were investigated. The results show that under the conditions of the plywood bonding strength to meet the national standard, modified attapulgite make the plywood formaldehyde emission decrease from 4.5 to 2.1 mg/L, the composite material can make the formaldehyde emission decreased to 1.6 mg/L, which can improved the indoor environment and the grade of plywood.
Self-Diffusion in Nano-ZnO
Authors: Kanmani S.S. , Ramachandran K.
Published: December 2010

Self-diffusion, both cationic and anionic, in ZnO nanoparticles was studied here in accord with reaction coordinate theory. The jump frequencies at various temperatures were computed. The isotope effect revealed that self-diffusion occurred mainly via a vacancy mechanism in nano ZnO; a result not previously reported in the literature.
Establishment of Relatively Unified Mathematical Model for Spiral Surface Based on Movement Characteristics of Particle
Authors: Song L.Z. , Guo S.L. , Xiang Chun Jiang , Hong Qi
Published: December 2010

From the viewpoint of the forming principle of spiral curve and classification from the kinematics, established relatively unified mathematical model of spiral curve based on the movement characteristics of particle and the forming principle of space surface shape, and in turn relying on relatively unified mathematical model of spiral curve, combined the similarity of forming movement between spiral curve and spiral surface, derived the relatively unified mathematical model of spiral surface with the concept of sequence of operator presented for the first time. The relatively unified mathematical model has been validated that it not only expressed the relationship of movement synthesis for commonly spiral surface’s forming movement, but also depicted new spiral surface to be required or named through changing parameters.
Research on NC Dressing of Involute Grinding Wheel
Authors: Ren Xiao Zhong , Wang Ya Hui , Su Jian Xin
Published: December 2010

Aiming at the dressing of involute grinding wheel, the mathematical model of involute interpolation is established. Taking the normal tolerance δ as accuracy index, the dense degree of interpolation points can be changed constantly with the change of developable angle increment △θ so that the numbers of interpolation points can meet the requirements not only for interpolating accuracy, but for interpolating efficiency. The wheel dressing software developed by using VC++ as programming tool can be applied for dressing the involute grinding wheel which can be used to grind involute gears with different teeth and modules. The results of simulation experiment verify the feasibility and correctness of the software.
Quantitative Analysis of the Extrusion Process of AZ31 Magnesium Alloy Based on Rough Set Theory and 3DFEM Simulation
Authors: Lou Yan
Published: December 2010

The effect of extrusion process on the quality of AZ31 magnesium extrudate was performed, by data mining from 3DFEM simulation and Rough Set Theory(RST). The weight of the effect of processing parameters and die structures can be obtained to predict the product quality, to optimize the extrusion processing and the die design. The results show that the effect of the billet temperature on the product quality is dominate, and its average weight is 0.25. The second important parameter is the ram speed and its average weight is 0.21. The third is the extrusion ratio. Its average weight is 0.18. In addition, it was also found that the effect of the die characteristic parameters on the extrudate is insignificant. Finally, the rationality of the weight of effect was verified through experiments.
Study on Cutting Force and Tool Wear of High Volume SiC/Al MMCs with Ultrasonic Vibration High Speed Milling
Authors: Xiang Dao Hui , Yue Guang Xi , Zhi Xin Tao , Gao Guo Fu , Zhao Bo
Published: December 2010

Particle-reinforcement aluminum-based metal matrix composites (MMCs) are widely applied in the aviation, aerospace and military fields due to their excellent physical and mechanical properties. But the further application of the materials is hampered owing to its difficultly machining characteristics. There are unique advantages while cutting hard and brittle materials with ultrasonic vibration. The ultrasonic vibration high-speed milling (ultrasonic milling) is a reasonable cutting method in which combined the advantages of high-speed milling (conventional milling) and ultrasonic milling. The machining performances of high volume SiCp/Al MMCs were studied by conventional milling and ultrasonic milling in this paper. The influences of the milling parameters on the milling force were investigated in the experiment. In addition, the wear and mechanism of tool were analyzed in ultrasonic milling. The results show that the cutting force, abrasive wear were reduced, and tool lives were increased effectively during ultrasonic milling of SiCp/Al MMCs.
Cutting Parameter Optimization Based on Force and Heat Constraint in Milling TC4 Titanium Alloy
Authors: Zhang Xiao Hui , Xu Xing Xin , Chen M. , Rong Bin , Liu Gang
Published: December 2010

With the rapid development of manufacturing technology, high speed, high efficiency and high performance have been the characteristics of metal cutting. And cutting technology has been faced with a lot of opportunities and challenges. But at the same time, cutting parameter optimization has gradually been one of the most outstanding bottle-necks that restrict the rapid enhancement of cutting technology. Since the essences of cutting process, such as cutting force and temperature, are invariable, force and heat constraint are performed here to optimize milling parameters of titanium alloy. Influences of cutting edge strength and cutting temperature on milling parameters are analyzed. Finally, feasible region of milling parameters are obtained.
Experiments and Analysis of Near-Dry Deep-Hole Drilling System
Authors: Hai Peng , Yuan F.
Published: December 2010

Based on the characteristics of near-dry cutting and BTA deep-hole drilling, this paper presented design method of near-dry deep-hole processing system, and then studied on it through experiments. The results show that the near-dry deep-hole processing system has better effects on discharge chips and coolant. At the same time, near-dry cutting function was better than BTA cutting with appropriate cutting parameters through comparing with BTA cutting machining.
Research on Dynamics Simulation of Milling Process for Frame Guide Plate Surface of Marine Diesel Engine
Authors: Fang Xi Feng , Wu Chun Qiao , Zhang Sheng Wen , Jia W. , Yang C.Q. , Tong Y.H.
Published: December 2010

In order to choose milling parameters quickly, reasonably and improve milling quality, avoid vibration in milling frame part of marine diesel engine, combining the development trend of milling technology, the dynamic model for milling the guide plate surface of frame part is built, the experiment modal parameters of spindle-holder with a cutting tool and the guide plate surface are identified. Using dynamic forces and chatter lobes to build constraint conditions, so as to recommend process parameters, which can show guidance to mill the guide plate surface of frame part. Consequently, parameters choosing lied on traditional try cutting is avoided, processing cost is reduced and the chatter free material removal rate (MRR) is improved.
Research on Processing Parameters of Large Lathe Bed's Vibratory Stress Relief
Authors: Yang Jian Xi , Cheng Y.Z. , Cui Feng Kui , Xu Hong Yu
Published: December 2010

In order to enhance the actual effect of vibration aging on large lathe bed and optimize it, many technological parameters of vibration aging will be discussed in this paper, including exciting force, exciting frequency and exciting point, etc. Finite element method is used to analyze the casting stress distribution and natural mode of vibration of a large lathe bed. After the analysis, it is found that the distribution of the residual stress of the lathe bed is extremely uneven. By analyzing parameters of the natural vibration model and the exciting force as well as the exciting point, a reasonable parameter will be got when the lathe bed is vibrating. The “Selecting low-frequency to avoid torsion mode” which reduces the deformation to bed caused by the residual stress, was proposed. The parameters have been proved effective through experiment, and the proposed approach can be used in the research of vibratory stress relief.
Modeling and Performance Analyzing of Helix Transmission Base on Modelica
Authors: Chen Jia Xin , Wang Hong Jun , Liu Chang Yu , Zou Xiang Jun
Published: December 2010

Picking manipulator ontology structure used rotation and translational motion pairs to join the components together, and then a multi-joint motion mechanism was built which meet the picking space requirement. According to the characters of growth space of litchi fruit, here used helix transmission as the first axes of the picking manipulator, to achieve motion in vertical direction. This study introduces the application of multi-domain modeling and simulation when constructing and simulating a helix transmission. Use object-oriented technology, multi-domain modeling and simulation language Modelica to construct the motion system which integrates motor model, signal detection module, signal processing module and parametric screw transmission model in Dymola simulation platform. Test the helix transmission by simulation, using the mechanical structure, sensor technology, signal processing technology. Simulation results show that, the modelica can provide a valid simulation for complex electromechanical system and support for parametric design.
Automatic Detection Apparatus Development of Steel Cord Conveyor Belt
Authors: Yun Y.N. , Zhang H.M. , Li C.J.
Published: December 2010

Steel core belts are widely used in long-distance, large capacity, large angle of mine, metallurgy, port, electricity and other departments of the large-scale transportation systems. According to incomplete statistics, this kind of belt accident 93.75% occurred in the joints and most are due to joints tic was not timely detected. Hence, non-destructive detection of belt is the key to the whole transportation system’s safety. For steel core belt automatic detection technology, deep research has been carried out at home and abroad. Detection apparatus was developed based on the electromagnetic theory and principle of X-ray, however, some varying defects existed in the industrial applications. Automatic detection apparatus of steel cord conveyor belt, developed by Pingdingshan Industry Polytechnic College and Shanxi Huaning Beier Measurement & Control Co. Ltd., integrated both advantages of electromagnetic detection and X-ray detection. It overcomes the difficulties of X-ray machine explosion proof and long time radiation. This kind of automatic detection apparatus has been installed and worked well in more than 30 mines and achieved good economic and social benefits since it was installed in Zhong Ping Energy Chemical Group’s 12th main slope conveyor.
Tool Cutting Edge Line Detection Based on Improved Hough Transform
Authors: Li P.Y. , Li Y. , Zheng Jian Ming , Zhang D. , Hao C.Y.
Published: December 2010

In view of the inherent limitations of classical Hough transform in the detection of line, an improved algorithm of randomized Hough transform is offered in this paper. The feature point sets are segmented based on the connected component labels in this algorithm. The elements of various point sets are stored in sequence so as to reducing the invalid samples. By using a valid line detection area and a dynamic storage management, the temporary storage units are gradually reducing with the iterative process. The speed of the line detection and the accuracy of identification can be improved, the storage space can be reduced, the computational complexity can be cut down and some unnecessary calculations can be avoided by using this algorithm. However, it still has the characteristics of the classical Hough transform that it is not sensitive to noise. The line edge where the cutting tool is on can be pinpointed. To achieve the vision-based mode of tool wear state, it can accurately detect rake and flank face of the cutting tool, and can effectively remove the influence to the tool wear detection from the BUILT-UP EDGE in cutting process. By the validation of testing examples, the algorithm has high speed, low memory occupation and high accuracy.
Application of Ubiquitous Sensor Network in Collection and Analysis of CNC Machine Tool Processing Status Information
Authors: Li X. , Yu Y.Y.
Published: December 2010

Because of the practical requirement of real-time collection and analysis of CNC machine tool processing status information, we discuss the necessity and feasibility of applying ubiquitous sensor network(USN) in CNC machine tools by analyzing the characteristics of ubiquitous sensor network and the development trend of CNC machine tools, and application of machine tool thermal error compensation based on USN is presented.
Error Calibration Technique of Laser Tracker and its Application
Authors: Yan Yong Gang , Wang Zhan Kui , Wang X.B. , Li Y.Q.
Published: December 2010

Laser tracker has widely been used in manufacturing industries, such as the industry of the large-scale machining tool, automobile, aircraft. So a high precision laser tracker is essential to satisfy the measuring requirements. In the paper the errors of laser tracker was analyzed and their calibration methods were discussed and studied. Then a calibration for laser tracker was carried on by using CMM and the measuring accuracy was verified. Finally, we demonstrate the application of laser tracker for detecting the large-scale machining tools. The measurement shows that the feeding straightnesses of tool rest in the two orthogonal directions are 0.0564 mm and 0.0309 mm in the working scope respectively. The results show the straightness of the body guide for the lathe meets the requirement, whereas the lathe tool workbench on the X axis direction does not and needs to be adjusted.
Conjugate Meshing Roller Chain for Timing Mechanism
Authors: Wang Yong
Published: December 2010

In this paper, new sprocket tooth profile is developed to reduce polygonal action and meshing impact under high speed. The new conjugated profile is derived by modifying involute profile to guarantee that the moving distance of chain is equal to the arc length of pitch circle that sprocket rotates at the same time and the centre line of chain at tight side is tangent to the pitch circle always. An asymmetrical modification method for the sprocket tooth profile is also proposed. The multi-body dynamic model of timing mechanism in engine with the intake and exhaust sprockets is developed. The fluctuation and meshing impact of chain are analyzed under different rotating speeds. The results show that new developed sprocket profile can efficiently reduce meshing impact and friction of chain. The stability of chain transmission under high speed can be improved.
Characteristics of the Transformations Occurring within the Intercritical Interval of Ductile Iron
Authors: Basso Alejandro D. , Martinez Ricardo , Sikora Jorge Antonio
Published: December 2010

Austempered Ductile Iron (ADI) and fully ferritic ductile iron are frequently used to produce safety parts. A new kind of ductile iron (DI), usually referred to as “dual phase ADI” is currently under development. The matrix of this new material is composed of ausferrite (regular ADI microstructure) and free (or allotriomorphic) ferrite. This combined microstructure is obtained by subjecting DI to heat treatments comprising incomplete austenitization stages at temperatures within the intercritical interval (three phase α-γ-Gr field of the Fe-C-Si stable diagram) followed by an austempering step in a salt bath in order to transform the austenite into ausferrite. This work describes some alternatives to control morphologies and amounts of phases present in the final microstructure. A revision of the results obtained on this matter by the authors as well as by other researchers is also provided. A ductile iron melt was produced in a metal casting laboratory. Samples were heat treated following different thermal cycles to obtain a wide range of duplex microstructures, containing different amounts and morphologies of microconstituents. The results account for the fact that the transformations occurring within the α-γ-Gr field are strongly affected by the chemical composition, previous matrix, and holding times. The role played by the microsegregation and availability of sites for heterogeneous nucleation is also worth noticing. Starting from ferritic matrices and holding the samples at constant temperature within the intercritical interval, austenite nucleation and growth take place mainly in the last to freeze zones. On the other hand, when starting from fully recrystallised austenitic matrices, allotriomorphic ferrite can precipitate during the isothermal holding within the intercritical interval at the austenite grains boundaries forming a continuous net. The kinetics of the γ  α transformation is notoriously slower than the α  γ one. The influence that part size exerts on the final microstructure is also analyzed.
Role of Lanthanum in Graphite Nucleation in Grey Cast Iron
Authors: Riposan Iulian , Chisamera Mihai , Stan Stelian , Stefan Eduard , Hartung Cathrine
Published: December 2010

Specific investigations concerning La-contributions in graphite nucleation process in Ca,Al,La-FeSi inoculated grey cast irons were performed by using a scanning electron microscopy (SEM, EDS). It was re-confirmed that complex (Mn,X)S compounds act as major nucleation sites for graphite flakes. La was mainly concentrated in the first formed oxide-based micro-inclusions (similarly to Al), but also at an important level in the shell of (Mn,X)S compounds (accompanying Ca). It is assumed that La forms micro-inclusions later than Al, as La-reached phase surrounded Al-reached phase. Complex Al-La small micro-inclusions, as possible better nucleation sites for (Mn,X)S compounds and La-Ca presence in the shell/body of these sulphides, possible better nucleation sites for flake graphite, appear to be the peculiar effects of ferrosilicon based inoculants, which include these active elements, promoting type-A graphite, inclusively in low S-grey iron.
Thermo-Mechanically Processed Multi-Phase Ductile Iron: Microstructure Development
Authors: Soliman Mohamed , Palkowski Heinz , Nofal Adel
Published: December 2010

Using thermo-mechanical simulator equipped with dilatometry system, two ductile iron alloys with different Mn-content are processed by combining both, well defined deformation process and subsequent controlled cooling in a single processing chain to control the final microstructure. Accordingly, ductile irons with four different structrues are produced namely, martensite, ausferrite, martensite+ferrite and ausferrite+ferrite. Depending on the dilatometric measurments, the ferrite formation temperature-range has been defined for both alloys. Preferential transformation of austenite to ferrite at graphite nodules during cooling is observed. It is also observed that the formation of ferrite during cooling results in both decreased martensite start of the undecomposed austenite and accelerated kinetics of ausferrite formation.
Influence of Boron Concentration on the Corrosion Resistance of High Boron White Cast Iron to Liquid Zinc Bath
Authors: Ma Sheng Qiang , Xing Jian Dong , Yi Da Wei , Zhang Jian Jun , Ma Sheng Chao , Liu Guo Feng
Published: December 2010

The influence of boron concentration on corrosion resistance of high boron white cast iron dipped into a pure liquid zinc bath at 460°C was investigated. The results reveal that high boron white cast iron containing 3.5 wt.%B exhibits excellent corrosion resistance due to the dense continuous netlike or parallel Fe2B phase which hinders the Fe/Zn interface reaction. The corrosion rate decreases significantly when the boron concentration increases, but the corrosion rate declines slightly when the boron concentration exceeds 3.5wt.%. EDS results indicate the coarse and compact δ phase generated near the matrix and a large amount of massive and blocky  phase occurred close to the liquid zinc. The corrosion process includes Fe/Zn interface reaction and the spalling and fracture of Fe2B. The failure of Fe2B is mainly caused by the microcrack of phase transformation.
Effect of Selected Alloying Elements on Mechanical Properties of Pearlitic Nodular Cast Irons
Authors: Serrallach Joan , Lacaze Jacques , Sertucha Jon , Suárez Ramón , Monzón Adrián
Published: December 2010

There is a continuous demand for low-cost nodular cast irons with improved mechanical properties, this being an industrial requirement both for pearlitic as well as for ferritic grades. Developments in pearlitic nodular irons should lead to alloys with higher and higher strength while retaining some ductility in the as-cast state so as to respond to demands related to castings for high power automotive engines in competition with steel castings and ADI. According to these aims, several alloying elements have been selected and added separately or combined to standard commercial nodular cast irons. In all cases, only low-level additions were made and their effects on the microstructure and mechanical properties at room temperature have been characterized and are discussed. A statistical analysis has been performed on the data obtained that accounts for changes in alloying additions as well as for variations in process parameters.
Literature Survey on Porosity and Microporosity in Cast Irons Related to Expansion and Gas Entrapment Phenomena
Authors: Anjos Vitor , Silva Ribeiro Carlos A. , Dias Fátima , Baumgart Wolfgang , Cunha João
Published: December 2010

Macro and microporosity in castings are a problem that persists at many foundries, despite the use of advance simulation software’s. This fact indicates that other parameters rather then the casting shape/design or the “standard” metallurgical characteristics are not properly controlled, considered or modelled in the solidification simulation.
In this paper we present the Phase I of a research project, which consists on a bibliographic review of the previous attempts to evaluate the relationship between solidification sequence and the measurement of expansion of molten metal during eutectic solidification and is relation to porosity and shrinkage defects.
On the Formation of Shrinkage Porosity in Gray Iron Castings
Authors: Elmquist Lennart , Diószegi Attila , Björklind Tobias
Published: December 2010

The formation of shrinkage porosity is a concern in the production of high-quality gray iron castings. In this work, a geometry known to generate this type of defect was used to investigate some of the parameters that influence its formation. The geometry is based on the presence of a migrating hot spot that at the end of the solidification is located close to the interface between the casting and the mold. The occurrence of shrinkage porosity at this position was investigated and the cavities examined using a scanning electron microscope equipped with EDS. It is believed that this type of defect is in contact with the atmosphere during solidification. The risk for shrinkage porosity decreases with increasing carbon content. The effect of high levels of molybdenum and phosphorus was investigated and shown to influence the defect formation. Inoculation is used to control the nucleation and the effect of high levels of inoculants was also examined. The microstructure was investigated by the use of a color etching technique, and the quantification considered eutectic cell size and secondary dendrite arm spacing. The quantification was done on the microstructure in the vicinity of defects as well as in areas without porosity.
Influence of Primary Austenite on the Nucleation of Eutectic Cells
Authors: Elmquist Lennart , Diószegi Attila , Svidró Peter
Published: December 2010

The solidification of gray cast iron starts with the precipitation of primary austenite. This phase nucleates either as columnar or equiaxed dendrites depending on whether nucleation occurs on the mould wall or on particles and impurities in the melt. In this work, the nucleation of primary austenite and its influence on the eutectic solidification has been investigated using different amounts of iron powder as inoculants. Besides, the influence of different cooling rates was also examined. Within each austenite grain there is a microstructure, and this microstructure was investigated using a color etching technique to reveal the eutectic cells and the dendritic network. It is shown how the cooling rate affects the dendritic network and the secondary dendrite arm spacing, and how the microstructure can be related to the macrostructure through dendrite arm spacing. The secondary dendrite arm spacing is a quantification of the primary austenite belonging to the primary solidification, and it will be shown how the eutectic cell size is related to the secondary dendrite arm spacing. The total amount of oxygen influences the microstructural dimensions. This effect, on the other hand, is influenced by the cooling rate. The number of eutectic cells versus eutectic cell size show two distinct behaviors depending on whether being inoculated with iron powder or a mixture of iron powder and commercial inoculant. The addition of a commercial inoculant decreases eutectic cell size and increases the number of cells, while iron powder almost only changes cell size.
The Effect of Semi-Solid Parameters on the Microstructure and Hardness of High Chromium Cast Irons
Authors: Inanlou Arash , Seyedein S. Hossein , Aboutalebi M. Reza
Published: December 2010

High chromium cast iron samples of 14% Cr and 24% Cr were produced in sand and permanent mold using semi-solid casting process. A series of experiments were carried out to clarify the effect of copper cooling plate and mold cooling rate on microstructure, particularly morphology and sphericity of primary austenite, hardness and heat treatment cycles. Results show that for 14% Cr and 24% cast irons casting at 10 and 15 degrees of inclined plate result in better sphericity and distribution of primary austenite and carbides. Moreover hardness comparison of both semi-solid iron alloys using copper cooling plate at of this special morphologies resulted from cooling plate investigated by making them heat treat at 1050 centigrade °C for 1 and 2 hours. Hardness results show both heat treated 14 and 24% Cr alloy in 1 hours have hardness comparable with those alloys traditionally cast optimum angles with respect to conventional casting show higher hardness in every condition. Effect but heat treated in 2 hours. Finally X-Ray diffraction pattern taken from specimens before and after heat treatment confirmed with observed phases in optical microscopy before and after heat treatment.
Statistical Inference of LZL-Type Mass Flowmeter Life Distribution Model
Authors: Zhou Zhen , Zhang L.N. , Qin Y. , Ma D.Z. , Niu B.
Published: December 2010

Characteristics of field failure data are analyzed in this paper. The failure data and sales
record of LZL-type mass flowmeter are used to infer life distribution of this conduct. The lines can be
fitted in coordinates of six distribution using least square and the residual sum of squares are
compared, the minimum correspond is the best distribution type. The results show that the life
distribution style of this conduct is the two parameter exponential distribution, which is the base to
analyze and predict failure development, research failure mechanism and draw up maintenance
policy.
Prediction Model of Surface Roughness for 2A70 Alloy Based on Orthogonal Test
Authors: Yu Xin Wei , Ma Xiao Hong
Published: December 2010

Influencing rules of surface roughness for the work-piece by changing major milling
parameters are studied when 2A70 alloy are cut by cemented carbide ball-end milling cutter cuts in
high-speed. Primary and secondary influence order of test factors are found out through range
analysis and variance analysis of test data according to the orthogonal test designed by the
manufacture experience. Influencing tendency between milling parameters such as feed per tooth,
back cutting depth, milling speed and line width and the roughness are obtained, a prediction model
of aluminum alloy surface roughness is built up, surface quality of the product can be predicted and
productivity can be analyzed.
The Study of Method for Calculating Geometric Average Sound Intensity in Scattering Field
Authors: Luo Feng Li , Li Guang Yu
Published: December 2010

When calculating sound intensity by indirectly measuring way, the sound pressures
obtained from two microphones should be mathematically averaged as the sound pressure of
measured point. The research showed that the method exists lower of allowable value in the high
frequency area. Using the geometric average value of two measured points to replace the sound
pressure of measured point, studying the measurement of sound intensity in scattering field, the errors
from which were compared. The result showed that the error of geometric average sound intensity
was more flat than that of mathematic average. So the sound intensity obtained from geometric
average sound pressure is more suitable for the measurement of a wider frequency range. And the
computing time is short, which can raise the measurement efficiency and the real-time of
measurement.
Theoretical Study on Rotating Platform Design for Platform-Based Lifting Fruit-Picking Vehicle in Mountainous Terrain
Authors: Dong Xi Bin , Wu Hao
Published: December 2010

The rotating platform is one of important components of the platform-based lifting picking
vehicle, which guarantees that the vehicle works well in mountainous terrain. Based on a brief
introduction of structural composition and function of rotating platform, the deflection mechanism of
rotating platform was analyzed theoretically. By analyzing the structural composition and calculating
DOF (Degrees of Freedom), the reasonableness of the scheme was verified and the kinematics
equations were established. According to the stability requirements of picking vehicle and the
characteristics of operating environment in mountain, the design theory for the support system of
rotating platform and its performance requirements were discussed, and further the important
structural parameters and design methods was studied.
Moving Character Analysis of a Novel 3-DOF Parallel Mechanism
Authors: San Hong Jun , Zhong Shi Sheng , Wang Zhi Xing
Published: December 2010

A novel 2-TPR/1-SPR spatial 3-DOF parallel mechanism is studied. The studied mechanism is composed of a moving platform connected to a fixed platform by means of three actuated limbs. The two of the three limbs are TPR serial manipulators and the other one is SPR serial manipulator. Each TPR limb consists of a Hoke joint T connecting to the fixed platform, a prismatic pair P, and a revolute pair R connecting to the moving platform. The SPR limb consists of a spherical pair S connecting to the fixed platform, a prismatic pair P, and revolute pair R connecting to the moving platform. Moving character of this mechanism are analyzed by using the theory of screws. The moving platform of this mechanism has one translational DOF, and it is translational moving along the normal direction of the plane which passes through the moving platform. The moving platform of this mechanism also have two rotational DOFs, and they are rotational moving that are rotated the lines which intersect each one of three binding line-vectors of the mechanism at the same time.
Chatter Detection in High Speed Machining of Titanium Alloys
Authors: Ding Song Lin , Izamshah R.A. R. , Mo John , Zhu Yong Wei
Published: December 2010

Chatter is a complex phenomenon characterized by unstable, chaotic motions of the tool
and by strong anomalous fluctuations of cutting forces. The situation becomes more serious in the
milling of titanium alloys because of their low Young modulus and extended elastic behaviour. This
paper presents an online chatter detection system based on the analysis of cutting forces, which is
one of the integrated modules of a multi-sensor chatter detection system consisting acoustic and
acceleration sensors. The cutting force is transformed into frequency domain by applying Fast
Fourier Transform (FFT). Chatter frequency is identified in the frequency domain by comparing its
power spectrum with predefined threshold. Experiments were carried out to validate the mythology.