bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanical Behaviors of Self-Piercing Riveting Joining Dissimilar Sheets
Authors: Huang Zhi Chao , Zhou Ze Jie , Huang Wei
Published: March 2010

This paper summarizes riveting tests and mechanical behaviors of Self-piercing Riveting (SPR) with semi-tubular rivet joining dissimilar metal sheets. The tests joining 2A12 aluminum sheet and DC01 steel sheet are carried out in lap-shear, coach-peel and cross-tension joint styles. The results show that SPR joining dissimilar materials of steel and aluminum alloy is feasible and riveting joints take on high mechanical behavior.
Finite Volume Simulation and Multi Parameters Optimization on Extrusion of Complex Aluminum Profile
Authors: Chen Ze Zhong , Bao Zhong Xu
Published: March 2010

In this paper, finite volume method (FVM) is adopted to simulate complex irregular aluminum profile extrusion process. The basic theory of FVM, the materials model, friction model, and a computer aided optimization (CAO) model based on orthographic experiments, artificial neural network (ANN) and genetic algorithm (GA) are presented. A complex aluminum profile extrusion is simulated and optimized. The results show FVM simulation is a good way for the description of material flow, and mesh distortion could be avoided effectively. Optimal values of multi parameters are also obtained. Experiment shows good fit among the simulation, optimization and the experimental results.
Characteristics of Underwater Swirling Plasma Arc Cut Quality
Authors: Wang Jia You , He C.H. , Li W.H. , Yang F.
Published: March 2010

The present work experimentally investigates the cut quality for underwater dual swirling plasma arc process at different operating gases. With a decrease in the oxygen content of the cutting operating gas, kerf shape and cut surface smoothness go well, but the adherent dross and cut hardness increase while cutting heat affected zone becomes wide. On the low-speed side of the cut, there are smaller bevel angle, more dross, and greater straightness and hardness. Compared with the dry plasma cutting, the underwater plasma process yields a cut of better shape but higher hardness.
Weld Pool Shape Variations and Electrode Protection in Double Shielded TIG Welding
Authors: Li Dong Jie , Lu Shan Ping , Li Dian Zhong , Li Yi Yi
Published: March 2010

A new welding method named double shielded TIG welding has been investigated and is described in this paper. It is applicable to the TIG process and can improve the weld depth/width ratio and protect the electrode from oxidation during the welding process. A two pipeline structure is designed in the torch. Pure inert gas passes though the inner pipeline which keeps the arc stable and protects the tungsten electrode. A mixed gas containing an active gas passes through the outer pipeline. The active element which is decomposed from the active gas dissolves in the weld pool so as to change the Marangoni convection from an outward to an inward direction, and, as a result, the weld pool shape becomes deep and narrow. The double shielded TIG welding method increases the weld depth by about 2~3 times over the conventional TIG welding. The effects of the active gas (oxygen) in the outer pipeline on the weld pool shapes are discussed. Heavy oxide layer is considered to weaken the Marangoni convection and changes the weld pool shape.
Microstructure and Performance Characteristics of Parts Produced via GMAW Surfacing Rapid Forming
Authors: Zhu Sheng , Li Chao , Shen Can Duo , Liang Yuan Yuan
Published: March 2010

The new metal-cored wires with Fe-Si-Mn-Ti-B microalloyed series were prepared to meet demands of GMAW surfacing rapid forming technology. The microstructure and performance characteristics of parts produced with them are both investigated. Its continuous metallographic microstructure along the deposition height direction shows obvious layered characteristic due to the special thermal cycles and cooling conditions. The microhardness values of intermediate sections of the part are higher than those of surface sections, which closely relates to their microstructure. The tensile strength, yield strength and broken elongation percentage of the part are 575MPa, 530 MPa and 10.14%, respectively. The fracture mechanism of the part belongs to quasi-cleavage crack. Therefore, the self-made metal cored wires are acceptable for forming some structure parts.
Experimental Research of Process Parameters in Metal Droplet Deposition Manufacturing
Authors: Chao Yan Pu , Qi Le Hua , Zeng Xiang Hui , Luo Jun , Huang Hua
Published: March 2010

In the droplet-based manufacturing process, the accuracy and density of forming parts are determined by experimental parameters such as the velocity and temperature of substrate, droplets spraying frequency, line deposition space and layer thickness etc. Using Sn60-Pb40, the droplets deposition experiment was conducted to investigate the effect of the parameters on the accuracy and density of formed lines, layers and solids on the experimental system. The experiment results showed that the high quality lines were obtained when the overlapping ratio of the adjacent droplets was controlled around 30% by the substrate velocity and droplet spraying frequency, meanwhile，the temperatures of the substrate and droplet were maintained at 270°C and 140°C, respectively. When the lines deposited space was about 90% of droplet diameter and the layer thickness was about 80% of droplet diameter, good deposition results of layers and solids can be obtained. This work has offered experimental guide for metal droplet deposition manufacturing.
Numerical Simulation and Evaluation of Local Thickness Increment in Ironing by Finite Element Method
Authors: Kotani Yuji , Watanabe Akihiro , Nishiumura Kazuki , Watari Hisaki
Published: March 2010

Local increases in product sheet thickness effectively contribute to reducing total product weight. Products could be designed efficiently if a designer could predict and control the thickness distribution of formed products. This paper presents a numerical simulation and evaluation of the local thickness increment of products formed during the ironing process. To clarify the mechanism of the local increase of sheet thickness, a 3-D numerical simulation during ironing was performed by the Finite-Element Method. Tool shapes (contact angles with the original materials and contact length of the punch with the material) that primarily affect thickness changes of original materials were evaluated. It was found that the sheet thickness distribution could be controlled if the original material were relatively thick, when appropriate manufacturing conditions could be selected.
Process Research on the Laser Rapid Manufacturing Technology
Authors: Zhang Kai , Liu Wei Jun , Shang Xiao Feng
Published: March 2010

Laser additive direct deposition of metals is a new rapid manufacturing technology, which combines with computer aided design, laser cladding and rapid prototyping. The advanced technology can build fully-dense metal components directly from the information transferred from a computer file by depositing metal powders layer by layer with neither mould nor tool. Based on the theory of this technology, an experimental setup for laser rapid manufacturing process was developed. Through this state-of-the-art automated apparatus, some cladding experiments were performed to grasp the process features of laser rapid manufacturing technology. Finally, the columnar/equiaxed grain growth transition model is used to explain the morphology characteristic. Accordingly, the appropriate microstructure can be obtained by adjusting the processing parameters.
Dual-Phase Materials Extrusion Process for Rapid Fabrication of Ceramic Dental Crown
Authors: Zhu Dong Bin , Xu An Ping
Published: March 2010

A novel ceramic forming process, dual-phase materials extrusion process based on solid freeform fabrication (also known as rapid prototyping), has been developed. It is a kind of selective slurry extrusion (SSE) technique previously proposed in our group. The dual-phase materials extrusion machine was constructed with micro-extrusion system and 3-axial positioning system. To demonstrate the usability of this machine, a functionalized dental crown was directly fabricated with support material and dental material from 3D model (STL format) of a human tooth. The fabrication time is usually in 20-50 min.
The Function of Magnetic Field in a Magnetic-Electrochemical Compound Polishing
Authors: Shi Li Min , Liu Er Liang , Niu Yong Jiang , Chen Yu Quan
Published: March 2010

Traditionally, the magnetic field is always vertical to the electrical field in a magnetic-electrochemical compound polishing.The magnetic field is set to parallel the electrical field in this paper. The mathematical model of the charged particles movement in a magnetic field is established through the analysis of its movement process when using Coulomb laws and Lorentz force. Through constructing the velocity formulation and loci formulation, the function of the magnetic field is proved. Because of the magnetic field, the concentration polarization of electrochemical reaction can be reduced more and the electrochemical reaction can be accelerated easily than the traditional polishing in which the magnetic field is vertical to the electrical field. Finally, to verify the model, the magnetic-electrochemical compound polishing process has been tested and the results, compared with those obtained from the model, have shown the movement model is reasonable and the analysis to function of magnetic field is correct.
Structural Analysis and Building an EDM Process Model
Authors: Zhou Ming , Meng Xian Yi , Wang Yue Jin , Gao Zhen Li , Dou Yun Ping , Tang Bo Yan , Yuan Mei Xia
Published: March 2010

The insufficient information about the mechanism of EDM process affects decision-making related to operation, parameter adjustment, and automatic control. Without a thorough understanding of the process dynamical features, it is difficult to determine a suitable model to describe such processes. This research employs the chaotic analytical techniques to determine the level of complexity of an EDM process; the correlation dimension method. With the understanding of the process complexity and its composition by correlation dimension analysis, a well-defined model is proposed. Finally, by using this model structure and size, an online time-varied predictive model was developed and verified by another experiment.
Mechanical Properties and Microstructures of Ferritic-Rolled High-Strength Interstitial-Free (IF) Steel Sheets
Authors: Guo Wei Min , Wang Zuo Cheng , Liu Sheng , Song Li Bin
Published: March 2010

High-strength IF steel sheet has increasingly attracted more attention of steelmakers in recent years as it has the potential to lighten the weight of automobiles and save energy and lower the production cost. In this paper, the effect of processing parameters on microstructures and mechanical properties especially deep drawability of ferritic-rolled P-added high strength Ti-stabilized IF steels were investigated and the precipitates in the steels were also analyzed. The results show that lubricant condition has great influence on the r-value and deep drawability of high-strength IF steels. And with the decrease of rolling temperature in ferrite region, the deep drawability of steels is improved.
Electrical Characteristics of Extended Gate FET Sensing Chip Constructed for Detection of DNA
Authors: Cao Zhong , Xiao Zhong Liang , Dai Yun Lin , Kamahori Masao , Shimoda Maki
Published: March 2010

An extended gate field effect transistor (EGFET) sensing chip has been constructed by using one gold plate electrode for molecule recognition and FET part for signal transduction. By using a 70.7mV DC voltage onto a Ag/AgCl reference electrode, the electrical characteristics of immobilization of the oligonucleotide probe of P1 and hybridization with the target single strand DNA of P2 on the EGFET sensing chip were examined in detail. The electrical signals on the change of a threshold voltage (VT) shift at a constant ID (3000μA) in VG-ID characteristic were obtained, and the VT shift value due to hybridization was calculated to be 12 mV, which may be attributed to the decreased negative charges after hybridization occurred at the gate surface. The surface density of hybridized dsDNA on gold surface of the FET was evaluated to be about 1 × 1012 molecules/cm2, indicating that the EGFET was a promising sensing element for biochip.
Influence of Specimen Sampling on Internal Residual Stress Test
Authors: Gong Hai , Wu Yun Xin , Liao Kai
Published: March 2010

Using Finite Element Method, the changing rules of residual stresses in the test specimen cut out from a quenched plate were analyzed, and suitable dimensions of the specimen for crack compliance method test was recommended. The results show that cutting has great influences on residual stresses in the specimen edge areas to a range of about one thickness, while it has little influences on stresses at the center part of the specimen; cutting mainly influences stresses normal to the cutting plane, while it has little effect on stresses parallel to the cutting plane; specimen with length bigger than 2.67 times the thickness and width bigger than 2 times the thickness is suitable for crack compliance method test, under these conditions peak stresses losing in crack compliance method results is less than 5% compared with surface stress X-ray diffraction results.
In Service Detection of 45 Steel’s Rotary Bending Fatigue Damage Based on Metal Magnetic Memory Technique
Authors: Xu Ming Xiu , Xu Min Qiang , Li Jian Wei , Leng Jian Cheng , Zhao Shu Ai
Published: March 2010

In order to study the relation between metal fatigue damage and the associated magnetic memory signals, the detection theory was studied based on magneto mechanical effect, and the rotating bending fatigue experiments on 45 steel were carried out combined with on-line data collecting system. The magnetic signals along axis at prefab defects in the fatigue process were studied. Experimental results show that the characteristics of the magnetic signals are different at every different stage of the fatigue process, in particular the magnetic signal changing faster in the late fatigue process, which indicates that it is feasible to detect fatigue damage using metal magnetic memory technique. Accordingly, the method is proposed to detect the rotation-bending fatigue damage for specimens in service by magnetic signals.
Intelligent Moisture Controlling System for Molding Sand
Authors: Xiao Hui Rong , Zhang Wei Wei
Published: March 2010

This paper presents a new intelligent moisture controlling system based on the resistance sensor for molding sand. A kind of moisture sensor with high sensitivity, simple structure and being suitable for on-line detecting is designed. A moisture measuring circuit founded on integrated method of frequency and period measuring is proposed. The circuit translates the relation between the sensor’s resistance variation and moisture into that of frequency and moisture, which makes the system to be capable of wide measurement range and high measurement accuracy. What’s more, the system has the features of strong ability of anti-interference and adaptation to remote measuring. Testing result shows that the moisture measuring and controlling accuracy of the proposed system can achieved ±0.2%.
Calibration and Registration for Inspection Robot with Contact Probe
Authors: Chen Yu Qing , Huang Jin , Xu Hui Pu , Ma Zi
Published: March 2010

This paper investigates the hand-eye calibration and points registration methods based on Cartesian coordinate’s transformation in armed robot inspection system. Different from traditional imaged based approach, the sphere radius of the inspection probe is considered; the hand-eye calibration and 3D points’ registration are both derived as constrained optimization problem. Matrix transformation of parameter separation is presented to get the approximate resolution. Finally, iterative cycles are provided to calculate the nearest points on designed surface corresponding to the inspection points. Experiment results illustrated the application of these ideas and demonstrated the validity of the proposed framework for inspection robots.
Visual Integrated Measurement on Geometry Parameters of Circular Saw Blade
Authors: Liu Qing Min , Zhao Ling , Dai Wei Feng
Published: March 2010

Established the circular saw blade visual measurement system and developed geometry parameters measurement software. Calculated the inner and outer circle diameters and the roundness error, the tooth angle and the radial rake angle, the radial direction clearance angle on the basis of image processing. Calibrated the measured part using the standard gauge block. Improved the circle and the line sub-pixel methods. Experiment results showed that the fitting error of improved least–square linear fitting method was quarter of ordinary least–square linear fitting error under small difference of orientation time. The diameters of the inner circle and the outer circle ,the roundness error ,the tooth cusp angle and the radial rake angle, the radial direction clearance angle were respectively 25.204mm, 193.624mm, 0.005mm, 59.999°±0.00695°, 15.004°±0.0104°, 14.997°±0.0137° while taken sub-pixel method.
Research on Measuring Path and Surface Fitting Algorithm for Non-Axisymmetric Aspheric
Authors: Pan Kun , Guo Yin Biao , Ke Xiao Long , Zhang Shi Han
Published: March 2010

In accordance with the requirements and characteristics of non-axisymmetric aspheric surface measuring, three measuring paths were put forward and estimated. The applicant situations of the three paths were also analyzed. A data processing system was created for the measuring of non-axisymmetric aspheric surface. Levenberg-Marquardt method was adopted as the nonlinear least squares to fit the discrete data. The fitting result was assessed by the fitting residuals. The experimental results show that the fitting residuals was in the 10-3mm magnitude when convergence index parameter set as 1×10-10mm. Compared with the theory equation, it’s shown that the method can not only be used for non-axisymmetric aspheric surface quality evaluation, but also can generate compensation data to improve machining precision.
The Design of VI-Based Synthesized Testing System for Belt Conveyors
Authors: Meng Wen Jun , Peng Wei
Published: March 2010

Because of the resistances to the belt’s motion in belt conveyors mainly caused by friction and frictional wear of the belt being one of key factors to effect its service life, the paper gives a simple qualitative investigation of frictional characteristic of the belt from its material behavior. Using stimulant coefficient of friction, it could make quantitative analysis for the resistances to the belt’s motion caused by friction etc, and design a belt conveyors synthesized testing system, the aim of the system is to test stimulant coefficient of friction under more type conveyors and more operating modes. Measurement and control of the system is based on VI(Virtual Instrument) software——LabVIEW, and in consequence it simplifies the hardware of the system, it also enhances human-computer interaction of the system’s operational interface.
Exploiting Critical Path Method for Evaluation of Conceptual Design
Authors: Wang Mei Yan , Shen Lian Guan , Deng Yi Min
Published: March 2010

Conceptual design is a critical design phase during which initial design solutions, called design concepts, are developed. These design concepts must be evaluated to ensure they satisfy the specified design requirements and the most appropriate design concept must be selected. It is often difficult for the designer, especially for the novice, to make an appropriate design concept evaluation and selection. Existing work on design evaluation lacks an effective tool for evaluating the temporal performance of the design concepts. To address this problem, a Critical Path Method (CPM) from project management is adapted for design evaluation, whereby a CPM network is converted from a causal behavioral process (CBP) and the methodologies relating to CPM are also applied to design improvement. A case study of a lever-clamp assembly system is also presented to illustrate as well as validate the method.
The Analysis of Failure Induced by Manufacturing Defect in Cu-30Ni Alloy Condenser Tube to Improve the Finished Product
Authors: Mao Xiang Yang , Fang Feng , Jiang Jian Qing , Tan Rong Sheng
Published: March 2010

During manufacturing Cu-30Ni alloy condenser tube, the defects such as crack were fatal to the successive processing operations. The cause of failure induced by manufacturing defect in Cu-30Ni alloy tube was investigated by employing nondestructive penetrative test technology, optical microscope, scanning electronic microscope with energy-dispersive spectrometer and tensile properties test. It was found that cracks including long continuous crack, short discontinuous crack and chevron crack were the main problem caused the manufacturing failure at the industrial production line. There were three principal evolutions of cracks, i.e., inter-granular, trans-granular and the combination of them. These cracks could decrease the elongation by about 10% in comparison with that of good tube, whereas it had no effect on yield ratio. From fractography around the crack, it was seen that there appeared to be different inclusions with different compositions. These inclusions were responsible for the manufacturing failure during the processing of the Cu-30Ni alloy tube.
Development of the Self-Adaptive Pipeline Cleaning Robot
Authors: Li Zhi Xiang , Li Zhi Hui , Li Yi , Wang Wei
Published: March 2010

In view of the existing pipe cleaning robot does not have the self-adaptive capacity to variable diameter pipelines and the whipping problems in the working process, a new style pipe cleaning robot is developed. This robot adopts umbrella's open-and-close mechanism, screw lifting mechanism and tail location navigation mechanism.This is a good solution to the stability of the robot work and improves its work efficiency. This paper describes the overall structure design and the key technique of robot, and the physical model of the robot is created. Finally, the experiment results indicate that the robot have a compact structure and reliable work.
Study of a Novel Approach of Active On-Line Balancing Device for High-Speed Spindle System
Authors: Ma Shi Lei , Dai Pan , Ma Qiu Shan , Xu Hua
Published: March 2010

A spindle can be very sensitive to mass unbalance which may have destructive effect on many types of rotating machinery, especially in high-speed rotating equipments. In this paper, a new active on-line balancing device based on static magnetic field with simple structures was proposed. The consecutive configuration of related stator and rotor was designed; the discussion focused on how the structural parameters influence the electromagnetic force. In the end, the influence of the misalignment of both spindle and core on the electromagnetic force was analyzed numerically under a given condition.
Research on Fatigue Damage of Ferromagnetic Material by Metal Magnetic Memory Methods
Authors: Liu Chang Kui , Zhang Bing , Chen Xing , Ren Ji Lin , Tao Chun Hu , He Yu Huai
Published: March 2010

Tension–tension fatigue tests of notched 18CrNi4A steel specimens were carried out under three different fatigue stresses, and metal magnetic memory (MMM) signals were detected. The effects of fatigue damage and fatigue stress on MMM signals were investigated. The results show that the absolute values of the feature parameters Hp(y)max, Hp(y)min and Hp(y)sub increase with the aggravation of the fatigue damage. There is an inherent relationship between the fatigue stress and the values of the Hp(y)sub; the larger the fatigue stress is, the larger the absolute values of the Hp(y)sub is. Fatigue-damaged locations can be effectively predicated according to the mutational character of the Hp(y) curve and the K curve, and zero-crossing points of the Hp(y) curve, respectively. Fatigue damage degree can be effectively predicated according to the value of the Kmax and the Hp(y)max, Hp(y)min and Hp(y)sub.
The Research on Process of Deep Cryogenic Treatment for W4Mo3Cr4VSi HSS Drill
Authors: Yan Hong Juan , Xu Hong Hai , Liu Ying
Published: March 2010

The Deep Cryogenic Treatment(DCT) process of W4Mo3Cr4VSi HSS was studied by orthogonal experiment method. The paper analysed the effect of various DCT process parameters on mechanical properties and observed microstructure before and after DCT treatment by the SEM. The results show that the effect of soaking temperature on the properties of drill is the first factor, the soaking time is second and the cooling rate is third. DCT enhances the transformation of austenite to martensite, and distributable carbide particles are precipitated from martensite. Therefore DCT increase hardness and enhance wear resistance of twist drill.
Compressive Response of UHMWPE/Vinyl Ester 3D Orthogonal Woven Composites at High Strain Rates
Authors: Sun Ying , Wang Guo Jun
Published: March 2010

The high strain rate compressive properties of UHMWPE/ vinyl ester 3D orthogonal woven composites are investigated experimentally. The composites are made from UHMWPE fiber 3D orthogonal woven preforms impregnated with vinyl ester resin by resin transfer molding. The samples are subjected to dynamic loading through the thickness direction using the Split Hopkinson Pressure Bar at three kinds of strain rate. The testing results are compared with the results of quasi-static tests on specimens with the same fiber volume fraction. The stress-strain relationships of UHMWPE/vinyl ester 3D orthogonal woven composites are rate dependent. It is found that the yield stress, strain at yield stress and modulus increased with the increased the strain rates. Additionally, the predominant failure mode of the composites under dynamic loading shear fracture from the optical microscopic images of fracture surfaces.
The Study on Oxidation Resistance Properties of Ductile Cast Irons for Exhaust Manifold at High Temperatures
Authors: Yang Yun Long , Cao Zhan Yi , Qi Yang , Liu Yong Bing
Published: March 2010

The oxidation behavior of two ductile cast irons was investigated in this paper. The alloys were a high Si-Mo ductile and a ductile Ni-Resist cast iron which were developed by FAW Foundry. Polished sections were exposed at temperatures between 800 °C and 1000 °C, mostly for 80h. It has been found that the property of oxidation resistance of ductile Ni-Resist cast iron is excellent or better than that of high Si-Mo ductile by comparison and analysis.
Studies on Corrosion Behavior of Q235 Steel by Iron Bacteria in Sedimentary Water from Storage Tank
Authors: Zhou Yong Zhang , Ni Xin , Han Dong Liang , Chen Dong Sheng , Chen Ye , Bai Zhong Zhong , Gu Bo Qin
Published: March 2010

In this paper, the corrosion behavior of Q235 steel by iron bacteria in the sedimentary water was studied by using static hanging piece method, and the corrosion characteristic was also studied by using potentiodynamic polarization curve technique and hysteresis loop methods. The results showed that, the corrosion current density of Q235 steel in iron bacteria was higher than in the sterile medium, and the corrosion potential moved negatively; Iron bacteria reduced the corrosion resistance of steel Q235; Anodic polarization curves of Q235 steel in iron bacteria didn’t showed passivation characteristic, and the cathodic polarization curves had obvious hydrogen depolarization characteristic; The presence of iron bacteria could accelerate the the pitting corrosion of Q235 steel.
Effect of Metal Powder on Blast Power of the Low Collateral Damage Ammunition
Authors: Yao Wen Jin , Wang Xiao Ming , Li Wen Bin
Published: March 2010

Traditional blast ammunition has a steel casing which turns into dangerous fragments after detonation. These steel fragments may kill civilians outside of the target. In order to adapt the need of fighting in an urban environment without hurting innocent bystanders in the process, one new kind of low collateral damage ammunition is put forward. The configuration and operational principle of this ammunition are introduced. From theoretical analysis it can be found the blast power is mainly determined by the metal powder. The effect of the metal powder’s type and magnitude on blast power is studied from static explosion test. In the test the overpressure curve is measured by the pressure sensor. The killing radius is computed from the sector target using the 25mm deal board. The initial casting velocity of the metal powder is obtained from the high speed photography. The results show tungsten powder is suitable for the low collateral damage ammunition, its diameter is about 50um. In this circumstance this ammunition can reduce collateral damage, however the damage effect is higher in the smaller area.
Effect of Forming Parameters on the Mechanical Properties of Thixomolding AZ91D Magnesium Alloy
Authors: Cui Xiao Peng , Liu Hai Feng , Zhang Tao , Liu Yong Bing
Published: March 2010

Magnesium alloy is the lightest metal that can be used as structural material at present. As a novel forming process for magnesium alloys, thixomolding can result in a product with few defects and superior dimensional accuracy, and it is suited to manufacture the thin wall products especially. In this paper, the samples of mobile phone housing were fabricated by 220Tons thixomolding machine made by Japan Steel Works. The effects of barrel temperature, screw rotate rate and injection velocity on the mechanical properties were studied. The relationship between process parameters and mechanical properties was investigated. The results show that the effects of barrel temperature and screw rotate rate on the mechanical properties can be divided to low temperature and high temperature stage. The high tensile strength are corresponding to the best injection velocity.
Research on the Mechanism of Aging of Dual Phase Steel Produced by Continuous Annealing
Authors: Yu Hao , Kang Yong Lin
Published: March 2010

The microstructure and properties of aging at room temperature of dual phase steel produced by continuous annealing were investigated by using mechanical property test, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). In order to know the mechanisms of aging of dual phase steel produced by this process, the relative theories of dissolution and diffusion of interstitials, dislocation and precipitation are proposed and discussed. From analysis, the results showed that dual phase steel produced by continuous annealing had high strain aging resistance after overaging.
A Study on the Characteristic of the Ultra-Thin Copper Bonding Wire
Authors: Hsu Hsiang Chen , Chang Wei Yao
Published: March 2010

In this paper, experimental procedures are developed to measure the tensile mechanical property of ultra thin Copper (Cu) wire (=1mil) before and after electric flame-off (EFO). Characteristics of free air ball (FAB), heat affected zone (HAZ) and as-drawn wire on 99.99% Cu wire have been carefully investigated by nanoindentation, microhardness and self-design pull test fixture, respectively. A secondary EFO technique has been conducted to reduce the strength of Cu wire and increase the bondability. The determined accurate material properties can then be applied to finite element analysis (FEA) for further reliability studies. A series of comprehensive parametric studies were conducted in this research.
Investigation on Correlation between the Modified Criterion and the Glass-Forming Ability for Metallic Glasses
Authors: Sheng Wen Bin , Zhang Chun Ming , Gu Wan Li
Published: March 2010

A modified criterion γ’ (=Tx/(1.5Tg+Tl) of glass-forming ability (GFA) for metallic glasses is suggested on the basis of present criterion γ (=Tx/(Tg+Tl) that correlates well with some systems including metallic glasses, some glassy oxides and some cryo-protective aqueous solutions. Results show that the modified criterion γ’ shows stronger correlation with the critical cooling rate Rc for metallic glasses than the criterion γ, which is demonstrated by a value increase in the statistical correlation parameter R2 from 0.9022 to 0.9037. Furthermore, a modified equation is given to reflect the relationship between γ’ and Rc.
Tribological Behavior of Irritation Cross-Linked UHMWPE under Dry Sliding
Authors: Wang Shi Bo , Ni Zi Feng , Ge Shi Rong
Published: March 2010

The cross-linked UHMWPE mixed with Vitamin E (VE) was prepared by hot press and then irradiated with gamma radial of 100 kGy does. The scratch hardness, micro-hardness and cross-linking density of cross-linked UHMWPE was measured. The tribilogical behavior also was examined. The experimental results indicated that the scratch hardness and micro-hardness of irradiation virgin and NC/UHMWPE are higher than that of virgin UHMWPE. Mixing VE decreased the cross-linking density of irradiated UHMWPE. Friction coefficients of virgin and cross-linked UHMWPE were seldom affected by irradiation and mixing VE. It was ranged from 0.35 to 0.37. Wear rate of virgin and cross-linked UHMWPE were strongly influenced by irradiation and mixing VE. Wear rate had an inverse proportional to the scratch hardness. The cross-linking and mixing VE in UHMWPE change the severity of adhesive wear of UHMWPE. For virgin UHMWPE, irradiated virgin UHMWPE and 0.1wt%VE/UHMWPE, the severity of adhesive wear was gradually decreased. Besides adhesion, poluging was the wear mechanism of irradiated 0.3wt%VE/UHMWPE.
Study on Amorphous Formation Ability of Al-Fe Alloy Liquids in Hot Dip Aluminizing
Authors: Zhang Wei , Fan Min , Du Zhi Qiang
Published: March 2010

The aluminized layer and the La-aluminized layer on 20 carbons steel were prepared by hot dip aluminizing method, and the microstructure and composition of the layer were investigated through scanning electronic microscopy (SEM), transmission electron microscope (TEM), X-ray diffractometer (XRD) and energy dispersive spectroscopy (EDS). The results showed that the amorphous phase was found in the surface layer of the hot dip aluminized steel. In order to study the phenomenon, the Al-Fe alloy liquids used in hot dip aluminizing were quickly solidified and slowly solidified respectively. The results showed that the amorphous phase was found in all Al-Fe alloy samples under the condition of the quick solidification. While the amorphous phase was only found in Al-Fe alloy sample with La under the condition of the slow solidification. Moreover, the pure amorphous alloy exists in the parts region of the sample, and the weight percentages of Al and Fe in pure amorphous alloy was 23: 2, and the amorphous alloy composition also contains a small quantity La. The formation mechanisms of the amorphous phase and behavior of La in the hot dip aluminized layer were also discussed.
Non-Conventional Approach for Deacidification of Fumed Silica
Authors: Chen Dong Hua , Fan Yun Ying , Hu Jin
Published: March 2010

A fluidized beds method used in the industry for deacidification of the fumed silica has several drawbacks. The present work was intended to develop a simple, rapid and cost-effective method for the deacidification of fumed silica with high specific surface area using microwave technique. The effect of microwave irradiation on the body of the fumed silica has been investigated. The experimental results show that the microwave irradiation technique has been effective in deacidification and suppressing the aggregation process of fumed silica. This new approach may be useful to accelerate the deacidification process and avoid the aggregation growth.
Microstructural Evolutions and its Influence on Properties of Super-Duplex Stainless Steel
Authors: Han Ying , Zou De Ning , Yao Hong Hong , Zhang Wei , Yu Jun Hui
Published: March 2010

Color-optical microscopy, energy spectrum analysis, hardness measuring, tensile and corrosion testing were conducted to investigate characteristics of microstructure, mechanical properties and corrosion resistance of S32750 super-duplex stainless steel aged at 850～920°C. The results indicate that with the increase of aging temperature and aging time the content of σ phase increases, while the ferrite content decreases. The forming and growing of σ phase obtained during aging causes an increase in hardness and a reduction in ductility of the aged steel. Moreover, increasing aging time the corrosion resistance reduces, owing to a new formed austenite occurs.
A Three-Phase Constitutive Model for TiNiNb Shape Memory Alloys
Authors: Wang Jun , Hao Zhi Ming , Shi Ping An , Yu Shao Rong , Li Wei Fen
Published: March 2010

A three-phase constitutive model for TiNiNb shape memory alloys (SMAs) is proposed based on the fact that TiNiNb SMAs are dynamically composed of austenite, martensite and -Nb phases. In the considered ranges of stress and temperature, the behaviors of austenite, martensite and -Nb phases are assumed to be elastoplastic, and the behavior of an SMA is regarded as the dynamic combination of the individual behavior of each phase. Then a macroscopic constitutive description for TiNiNb SMAs is obtained by the conventional theory of plasticity, the theory of mixture, the theory of inclusion, and the description of phase transition by Tanaka. The method for determination of the material parameters is given. This constitutive model can describe the main characteristics of SMAs, such as ferrcelasticity, pseudoelasticity and shape memory effect.
The Correlation between the Liquid Structure and the Viscosity of Sn-Cu Lead-Free Solders
Authors: Pan Xue Min , Zhao Ning , Ding Rui Fang , Wei Guang Lin , Wang Lai
Published: March 2010

The liquid structure of two lead-free solder Molten alloys, Sn-0.5Cu and Sn-1.8Cu (wt.%), has been examined using X-ray diffraction method. The main peak for liquid structure of Sn-0.5Cu is similar to that of pure Sn. A pre-peak has been found in the low Q part on the structure factor S(Q) of Sn-1.8Cu tested under 320°C, but it disappeared finally when the testing temperature reached 350°C. The both viscosity was measured using a torsional oscillation viscometer. It was found that the anomalous variations of viscosity had a direct relation with the transition of the liquid structure, which is consonant with the results of high temperature X-ray diffraction. The microstructure of the solder matrixes as well as interfacial reaction between liquid solders and Cu substrates was also studied. The results show that particle-like Cu6Sn5 intermetallic compounds (IMCs) emerge in Sn-1.8Cu solder matrix. The IMC layer at Sn-1.8Cu/Cu joint is thicker than that at Sn-0.5Cu/Cu interface. The correlative effect of liquid structure on phase evolution in the solder joints is analyzed.
The Stereoscopic Morphology of Martensite in Ferrous Alloys
Authors: Ma Yue Xin , Wu Yu , Yang Shao Kui , Wang Long , Tan Yu Hua
Published: March 2010

The space morphology of martensite in 15, 45 and T9 steels quenched from high temperatures had been observed under a scanning electron microscope using a thin-foil specimen which were deeply etched. The results show that the space appearance of packet martensite is not lath-like in shape, but sheet-like in low carbon steel, and thin plate-like in medium and high carbon steels. The stereoscopic models of two kinds of packet martensite, named sheet-like and thin plate-like martensite by authors, were proposed.
Effect of Electrical Current on Wear Rate of Nano-Al2O3p/Cu Composite
Authors: Guo Xiu Hua , Song Ke Xing , Liang Shu Hua , Wang Qing , Wang Yong Peng
Published: March 2010

The nano-Al2O3p/Cu composite performed in this paper was prepared by internal oxidation. The nano-Al2O3p/Cu composite wire and the Cu-Ag alloy wire were slid against a copper-based powder metallurgy strip under unlubricated conditions. The wear behavior of nano-Al2O3p/Cu composite and Cu-Ag alloy were researched under different currents from 0~50A and sliding distance from 0~72Km. Worn surfaces of the nano-Al2O3p/Cu composite were analyzed by scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS). The results indicate that the nano-Al2O3p/Cu composite surface is dispersed with Al2O3 particles having a size of 10~20nm; the wear rate of both 0.60Al2O3p/Cu (containing 0.60wt.% Al2O3) composite and Cu-Ag alloy increases with the increasing electrical current and sliding distance, which increases abruptly at the beginning and smoothly subsequently; The wear rate of Cu-Ag alloy is 2-5 times that of 0.60Al2O3p/Cu composite without electrical current; The wear rate of Cu-Ag alloy is 5-10 times that of 0.60Al2O3p/Cu composite with electrical current of 30A-50A; The sensitivity of electrical current on the Cu-Ag alloy is more apparently than that on 0.60Al2O3p/Cu composite. Adhesive, abrasive, and electrical erosion wear are the dominant mechanisms during the electrical sliding processes.
Effect of Heat Treatment Process on Microstructure and Mechanical Properties of SWRS82B Wire Rod
Authors: Zhang Jia Qi , Liang Yi Long , Xiang Song , Yang Xiao Di , Yang Ming
Published: March 2010

The effect of the heat treatment process parameters on the mechanical properties and microstructure of SWRS82B wire rods were investigated. Specimens were austenitized at 850°C~900°C and held at 500°C~600°C. The results show that the interlamellar spacing and the pearlite block size become finer with the decrease of the isothermal temperature. At the same isothermal temperature condition, the interlamellar spacing decreases with the increase of austenitizing temperature. The fine interlamellar spacing increases the yield strength and ultimate tensile strength.
3-D Finite Element Analysis of Bonded Joints under Impact Loading
Authors: You Min , Yan Jia Ling , Zheng Xiao Ling , Zhu Ding Feng , Hu Jing Rong
Published: March 2010

The effect of the adhesive thickness and elastic modulus on the stress distribution in the mid-bondline of the adhesively-bonded steel/steel joint under impact loading is analyzed using 3-D finite element method (FEM). The results show that the stress distributed in bondline near the interface was significantly affected by the adhesive thickness and the elastic modulus. When the thickness increased from 1 mm to 2 mm, the values of all the stress components increased evidently along the upper edge of the adhesive but decreased significantly along the lower edge near the loading face. When the elastic modulus of the adhesive was increased, all the stresses increased along either the upper or the lower edge. It is clear that the suitable thickness and the elastic modulus of the adhesive are very important when the adhesively bonded joints subjected to the impacting load.
Research on Heat Treatment Influence Factors on High-Pressure Cylinder Steel 30CrMo-M
Authors: Huang Zhong Guo , Dong Hong Lei , Yuan Qing Hua , Jin Shun Yao , Fan Jia , Li Qun
Published: March 2010

To increase comprehensive properties of cylinder steel, high-pressure cylinder steel 30CrMo-M was developed on the basis of steel 30CrMo. Tests and researches were made on factors which influence heat treatment properties, such as chemical composition, quenching temperature, and tempering temperature. The results indicated that the 30CrMo-M steel has stable chemical composition, its strength rises with increase of carbon equivalent, and thus it has better relativity. When concentration of quenching liquid is 5%, yield ratio of the steel can be guaranteed to be low, thus safety of cylinder is improved. Tempered between 570°C~622°C, the strength of the steel is increased and plasticity rises with increase of temperature. When tempered at 570°C, inner wall structure of cylinder contains tempering martensite, the strength is high but the plasticity is low. When tempered between 610°C~615°C, temper brittleness happens very easily and toughness is on the low side. The best heat treatment technology is: quenched at 930°C with temperature holding for 40 minutes and quenching liquid concentration as 5%, tempered at 580°C with temperature kept for 90 minutes. The microstructure treated by this technology is tempered sorbite with higher strength, plasticity and toughness.
Study on Static Deformation Characteristics of Mental Rubber Material
Authors: Li Dong Wei , He Zhong Bo , Ren Guo Quan , Zhang Lei
Published: March 2010

Mental rubber material is a new kind of high elastic and large damping material. In this paper the static deformation of mental rubber components had been studied from stretch, compression and shearing experiment. By the method of high-order polynomial fitting, the empirical formula of static deformation characters of mental rubber component had been established, and some deformation rules of mental rubber had been obtained.
Stress Relaxation Analysis of Polyurethane Foam Preloaded Structures
Authors: Xu Bing , Fan Zhi Geng , Yu Shao Rong , Niu Wei
Published: March 2010

Based on the nonlinear finite element analysis method, FEA models which describe the viscoelastic friction contact state of the polyurethane foam preloaded structures are created. In the simulations, the general Maxwell viscoelastic constitutive relation is introduced and a seven-parameter general Maxwell viscoelastic model is used to fit the experimental stress relaxation curve of polyurethane foam. During the nonlinear contact analysis, coulomb friction law is adopted, and the effects of the coulomb friction coefficient on the reaction force in the axial direction are analyzed. The FE results show that the change tendencies of relation curves of the structures are similar to which of the polyurethane foams. In the end, the influences of stiffness ratio of polyurethane foam to the outer component on the structural relaxed force are discussed, and the FE results indicate that the stiffness ratios affect the stress (force) relaxation degree remarkably. That is to say a good structure design could optimize the mechanical performance of the complicated structures greatly.
Yield and Rheological Behaviors of Magnetorheological Fluids
Authors: He Jian Min , Huang Jin , Liu Cheng
Published: March 2010

Magnetorheological (MR) fluids are materials that respond to an applied magnetic field with the change of their yield and rheological behaviors. In this paper, the yield and rheological behaviors of MR fluids are discussed. Based on the microstructure of magnetic chain a theoretical model is developed to analyze the effect of an applied magnetic field on the yield stress of MR fluids. Bingham model is used to describe the rheological behaviors of MR fluids subject to an applied magnetic field. The results show that altering the strength of an applied field can control the yield stress of MR fluids. The shear stress increases as the strength of an applied magnetic field increases, and it hardly changes with the increase of shear strain rate. MR fluids exhibit Bingham plastic model.
Sustainable Manufacturing Technology and Properties of Steel Slag Concrete
Authors: Li Yun Feng
Published: March 2010

Early-age deterioration of concrete due to cracking and higher maintenance cost for poor durability cause serious troubles to concrete structures. Steel slag is a solid waste discharged in large quantities by the iron and steel industry. Steel slag includes a certain scale mineral such as C2S and C3S, and can be applied in cement and concrete as mineral admixtures. When mineral admixtures with steel slag powder and blast-furnace slag powder are mixed into concrete, the performance of concrete can be improved further. Mineral admixtures with steel slag powder as partial replacement for Portland cement in mortar is an effective means for enhancing abrasion resistance. Steel slag powder can be used to reduce cracking in concrete at early age, so that it will improve the durability of concrete structures.