bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation on the Weldability of a Zr-Ti Microalloyed Pipeline Steel X120
Authors: Yin Yu Qun , Wang Hong Hong , Yao Yong Kuan , Li Li , Lei Xuan Wei , Zhao Jin Bin , Wu Kai Ming
Published: June 2012

Welding thermal cycle simulation with the heat input of 12~25 kJ/cm and practical welding were undertaken to investigate the weldability of a Zr-Ti microalloyed pipeline steel X120. The microstructure in the simulated coarse-grained heat-affected zone was predominantly bainite. The Vickers hardness and room temperature impact toughness of simulated coarse-grained heat-affected zone is 276~297 (HV10) and 208~225 J, respectively. These results indicated that the X120 steel had good weldability. Practical plate welding with the heat input of 21 kJ/cm also showed that the Zr-Ti microalloyed pipeline steel X120 had high yeild strength (895 MPa) and low temperature (-30°C) impact toughness (183 J, 204 J and 208 J in the fusion line, coarse-grained heat-affected zone and fine-grained heat-affected zone, respectively).
Research of Laser Welding for Hot Rolling Si-Steel Strip
Authors: Zhong Ru Tao , Huang Zhi Jun , Wang Liang
Published: June 2012

Aim to the question of laser welding easy rapture of hot rolling Si-steel strip. Utilize the Trumph TLF12000 fast-flow CO2 laser, and the method of laser welding, laser welding with filling wire and laser welding with normalize, the laser welding characteristic and mechanical performance of 50ww600 hot rolling Si-steel strip have been studied experimentally.The technology of improving the welding performance has been probed into.It include that the softing of laser welding lead to break easily. The question may be solved by the method of laser welding with filling wire.
Study on Fatigue Strength of Welding Joint in Wuhan Iron and Steel
Authors: Fan Zhen Ping , Wu Xiao , Li Qiang
Published: June 2012

As abrupt change of the shape and elastic constant in the weld area occurs to the welding joint, there will be obvious stress concentration near the weld area when being loaded. Lifting and Lowering Method and Grouping Method prevailing in the world are applied to conduct an experiment about fatigue strength of a certain welding joint in Wuhan Iron and Steel and S-N curve is drawn in this paper based on the condition of nominal stress. In addition, the influence of weld size of the welding joint on the distribution of stress is studied through the calculation of finite element numeral value and experimental test. According to the factor of stress concentration, S-N curve is modified to provide the data support for the application of the welding joint and assessment of fatigue strength.
The Research of Solar Film Reactor Technology Designing
Authors: Liang Su Tao , Lu Jin Xi , Ji Jiang Hai , Gao Liang , Li Hong Wei , Liu Hong Quan
Published: June 2012

In view of the Membrane Bio-Reactor(MBR)'s common energy consumption and higher operating costs in domestic and overseas, we designed a solar MBR process, the design process is using solar energy to directly carry out the thermal conversion, and complete membrane bioreactor Oxygen demand and membrane pressure process of the work process without motor,blower or water pump. The reactor can make the energy consumption and operation cost greatly reduced, and the operating costs can be reduced by 56% to 78%.
TEM and DSC Analysis of LT-3 Aluminum Alloy Vacuum Brazing
Authors: Xu Jing Nian , Cao Xiu Li , Feng Tao , Zhang Yong Ang
Published: June 2012

Crystallization of aluminum alloy directly affects the brazing beam quality. The transmission electron microscopy (TEM) was used to measure lattice parameter of aluminum in the brazing beam. And the differential scanning calorimeter (DSC) was used to measure endothermic and exothermic reaction in the vacuum brazing process. The experiment results indicate that the latent heat of crystallization in the crystallization is –370.7J/g, the critical work of nucleation is 3.82×10－17J, the critical radius of nucleation is 8.69×10－10m, the volume of critical crystal nucleus is 2.75×10－27m3 and the per unit cell in critical crystal nucleus is 43, the number of atoms is 172, in the actual crystallization the number is less than 172.
An Weld Line Optimization System of Tailor Welded Blanks Based on Compensation Principle
Authors: Liu Yu Shan , Xu An Ping , Zhu Dong Bin , Guan Xiao Tian
Published: June 2012

Currently, the consistency of tailor welded blanks ( TWBs ) with the design part is receiving more attention owing to the extensive use of TWBs. An approach based on compensation principle is proposed in this paper, which reduces the deviation between the design weld line and the actual weld line after forming of TWBs. Firstly an optimization model based on the offset of the blank weld line of TWBs is built. Then a C++ program is developed as the external customized optimizer. It bases on the FEM simulation software HyperWorks. At last, a example using the approach is provided, and the results show that the method is practicable.
Numerical Simulation of Double-Sided Double Arc Welding without Back Chipping Based on MSC.MARC
Authors: Gao Li , Tan Ye Fa , Cai Bin , He Long , Dong Gui Yang , Yang Zi Shuang
Published: June 2012

Numerical simulation based on MSC.MARC was applied to predict the residual stress in double-sided double arc welding (DSDAW). The distribution of residual stress field in the welding seam was simulated and the actual situation in experiment of the residual stress was also measured. It shows that the calculated results are in good agreement with the experimental ones. The residual stress of conventional welding (CW) or a single arc welding (SAW) is calculated too. Moreover, the welding residual stress field of thick metal plates welded by DSDAW was carried out and compared with that of the CW method with back chipping. The result shows that the DSDAW technology had some excellent characteristics of smaller angular deformation, lower residual peak tensile stress, and well-proportioned stress distribution, which testifies that the welding procedures in DSDAW are reduced and the welding efficiency and quality of the welding joint are improved in great margin.
Effect of Welding Method on the Hardness of Joint of 600MPa Grade New Generation Steel
Authors: Huang Zhi Jun , Hu Lun Ji , Pen Tao , Wang Yu Tao , He Jia
Published: June 2012

Laser-MAG hybrid, GMAW and SAW welding experiment were carried out for the new low CE 600MPa grade steel, and hardness survey on the welded joints was performed. Laser-MAG hybrid welding has the highest speed with the least filling weld metal, and its joint exhibits almost no softening with higher harness in weld than base metal. SAW welding has high efficiency but most significant softening effect on the HAZ. For SAW, on the HAZ 4 ~ 5 mm apart from the fusion line peak hardness exists. For GMAW, on the HAZ about 2mm away from the fusion line a softened zone appears, but the softening degree is lower than for SAW. The results showed that the hardness of the welded joint of this type of steel seems much subjected to the welding heat input.
Joining Refractory Metals for High-Temperature Applications
Authors: Lin Chia Chen , Shiue R.K. , Shy Hsiou Jeng
Published: June 2012

Brazing Mo/Mo and Mo/porous W using 60Mo-40Ru in weight percent braze alloy are evaluated in the experiment. Sound Mo/60Mo-40Ru/Mo joint is obtained from brazing at 1970 and 2000 °C for 600 s, respectively. The brazed joints are comprised of σ and Mo-rich phases. For Mo/60Mo-40Ru/porous W joint, sound bonding is achieved only from brazing at 2000 °C for 600 s, and similar microstructure of the joint is obtained. The 60Mo-40Ru braze alloy shows potential in bonding refractory metal(s) for high-temperature applications.
On Construction and Verification of a Safety Model
Authors: Wang Chen Hua , Liu Yu Jung
Published: June 2012

This paper, conducted through the literature reviews of safety culture models and safety culture dimensions and the application of the management mechanism of the Taiwan Occupational Safety and Health Management System (TOSHMS), proposes a new Omnidirectional Safety Culture Model (OSCM). Four railway companies in Taiwan served as the questionnaire survey subject, and the safety culture of the current railway industry was profoundly investigated. Furthermore, utilizing AMOS analysis software, the thesis verifies the hypotheses by inspecting the structure model with Structural Equation Modeling (SEM).It was indicated in the research that the railway employees’ evaluation of safety culture Significant differences are noted between age and most safety culture dimensions other than “Safety Encouragement and Punishment,” “Performance Measurement,” and “Procurement Management.” In addition, job satisfaction, working environment satisfaction, safety and health policy satisfaction, working efficiency, and possibilities of workplace injuries bear obvious relevance to many safety culture dimensions. The goodness of fit of four safety factors and eighteen safety culture dimensions are confirmed to be acceptable, considering the evaluation result of safety culture structure on all models and synthesizing overall fit indexes. It is ascertained that this model fits better and the result is effective.
Experimental Research on the Bond Strength Influenced by Mortar Corrosion
Authors: Xu Hong , Yao Guang Hua
Published: June 2012

The mortar cube specimens and anchorage specimens are corroded under the sulfate solution and dry-wet cycle method is used to accelerate the corrosion process. The compressive strength of cub specimens and bond strength of anchorage specimens of different corrosion time are tested and the corresponding relationship between mortar corrosion degree and mortar anchorage strength is established。The test result shows that: the curve that strength of mortar specimens changes with corrosion time fitted with quadratic curve significantly, and the high water cement ratio is , the faster the strength loss. After mortar corrosion, the bond strength decreases with corrosion time linearly, the high water cement ration is , the low initial bond strength the specimens has, and the little bond strength loss at the same corrosion time. The changes of bond strength with coefficient of compressive corrosion resistance coefficient is approximately lineally.
Study of Relationship between Inorganic Polymer Concrete Cracks and Deflection Based on Fractal Theory
Authors: Lu Zhe An , Yan Yan , Fan Xiao Chun , Cao Ding Guo , Li Jian Ju , Wang Yin Ping
Published: June 2012

Inorganic polymer concrete（IPC） is a new building material, since it has abundant raw materials, inexpensive, and has little pollution to environment during its manufacturing process and needs little time to condense to high strength; these have caused the domestic and foreign material researchers of great interest. The flexural failure process of inorganic polymer concrete beam was studied based on the mechanical test, study the stiffness of inorganic polymer concrete beam,and fractal analysis were done of the crack pictures getting during the test process by using MATLAB program and the results show that: the tenacity of inorganic polymer concrete beam is better than portland cement concrete beam,the crack development of inorganic polymer concrete beam has fractal feature; The relationship between box dimension and deflection of the beam is analyzed and the quantitative relation curves of them were fitted.
Characterization of Fatigue Damage of Crankshaft Remanufacturing Core by Two-Dimensional Magnetic Memory Signal
Authors: Xue Nan , Dong Li Hong , Xu Bin Shi , Chen Cheng , Dong Shi Yun
Published: June 2012

Fatigue damage degree of crankshaft remanufacturing core was studied based on Metal Magnetic Memory Testing. Bending fatigue test of crankshaft remanufacturing core was conducted on the resonant fatigue test rig and variations of two-dimensional magnetic memory signal distribution in crankshaft pin fillets were studied at different bending fatigue cycle. Experimental research shows that distributions of Hp(x) signals, namely, tangential component of spontaneous stray field and Hp(y) signals, namely, normal component of spontaneous stray field in crankshaft pin fillets have no obvious change with loading cycle when no crack initiation and propagation occur in crankshaft pin fillets. Characteristics of Hp(x) and Hp(y) signal both show dynamic variations when crack in crankshaft pin fillets initiates and extends at medium rate or high rate. Metal Magnetic Memory Testing is a dynamic method for monitoring fatigue crack propagation in crankshaft.
Flow Stress Behavior of 2205 Duplex Stainless Steel during Warm Tensile
Authors: Zhang Ji Xiang , Li Zheng Jun , An Guo Yin , Wang Zhi Xiang
Published: June 2012

The flow behavior of 2205 duplex stainless steel for ship sheet in the strain rate ranging from 0.001 s-1 to 0.1s-1 and temperature ranging from 473K to 1073 K is studied on AG-10TA universal material testing machine. The results show that the 2205 duplex stainless steel is a strain rate sensitive material, and the flow stress increases with the increase of strain rate and decreases with the increase of temperature. The average elongation of the 2205 duplex stainless steel is above 25% with the temperature ranging from 473K-873K, and the elongation is above 47% at 1073K; At last, the flow stress constitutive equation is established based on the Browman model, which describes the flow stress behavior of 2205 duplex stainless steel in the temperature ranging from 473K-873K. The curves predicted by the constitutive equation agreement with the experiment data well.
Preparation of Lead Zirconate Titanate Thin Film Using Magnetron Sputtering
Authors: Yu Li Yang , Wang Yang , Yao Guo Hua
Published: June 2012

PZT(lead zirconate titanate) piezoelectric thin films were deposited on the glass substrates by RF (radio frequency) magnetron sputtering reaction method. The XRD(X-ray diffraction) analysis is used to characterize the structure of thin film, the pattern of EDS(energy dispersive spectrometer) shows the composition of thin film, and SEM(Scanning Electron Microscopy) is used to study the morphologies of thin films. The influence of different sputter gas content on the crystalline quality and the surface morphology are also investigated. The results demonstrate that volatile of lead oxide is closed to the ratio with the oxide content. The roughness of the thin film is influenced by the crystalline quality.
High Cycle Fatigue Tests at High Temperature under Superheated Steam Conditions
Authors: Džugan Jan , Misek Tomas
Published: June 2012

Increasing demand for reliable design of all kinds of structures requires materials properties evaluated under the conditions as close to real service conditions as possible. Presently resolved project dealing with development of new turbine blades geometry requires better understanding of the material behavior under service conditions. Service conditions of turbine blades are cyclic loading at high temperatures under superheated steam conditions. There are not commercially available testing systems providing such functionality and the system allowing samples loading under considered conditions is to be proposed. The paper deals with development of the testing equipment and testing procedure for high cycle fatigue tests in superheated steam corrosive environment. The system allowing cyclic loading at temperatures up to 650°C under superheated steam conditions was successfully designed, assembled and tested on series of testing samples.
The Analysis of the Stress and Strain in Skew Rolling
Authors: Yang Hai Bo , Zhang Li Jie , Hu Zheng Huan
Published: June 2012

In this paper, three-dimensional finite-element model for the skew rolling (helical-groove rolling) process has been used to characterize the workpiece material stress,strain and deformation behavior. Particular attention has been paid to representative cross section and the center, edge and mid-radius points of the billet
Study of Design Procedures for Partially Prestressed Concrete Pier Cap Beam
Authors: You Qi Yong
Published: June 2012

The paper analyzed the key points in design of partially prestressed concrete pier cap beam. Design ideal and design method of partially prestressed concrete pier cap beam were elaborated. Results between deformation and stress were compared. Which shows that partially prestressed is more excellent than fully prestressed in long-span concrete pier cap beam.
Microstructure Characterization of the Reaction Interface between CBN Grain and Titanium-Deposited Film
Authors: Ding Wen Feng , Liang Yang Min , He Jian , Tang Li , Yu Jie , Liu Zhi Wu
Published: June 2012

Cubic boron nitride (CBN) abrasive grains with surface titanium-deposited film were heat-treated during 550-950°C for 60 min under high vacuum circumstance. Detailed interfacial compounds analysis by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersion spectrometer (EDS), differential thermal analysis (DTA) indicates that the interfacial reactions are much dependent on the heating temperature to some extents, and the reaction products, TiN, TiB2 and TiB chiefly form the network structure. In particular, at 950°C the transition layers with excellent performance, CBN/TiB2/TiB/(TiB+TiN)/TiN/CBN, is realized.
The Study of Metal Diffluent Law in Multidirectional Active Loading
Authors: Cheng Mei , Zhang Zhi Min , Yu Jian Min
Published: June 2012

In this paper, the deformation characteristics of workpiece of different deformation parts was experimented in multi-dimensional loading conditions, The research shows that the metal around active mode follows priority deformation principle when selectable multi-dimensional flowing. Through the analysis of deformation resistance and driving force, the influence factors of selectable multi-dimensional flowing was determined, and the mathematical model of selectable multi-dimensional flowing was established, the theoretical basis of priority deformation in local loading area was provided, a powerful guarantee was provided for precise design multi-dimensional process.
Finite Element Analysis of Aluminum Alloy Pitting Stress Concentration
Authors: Hui Li , Zhang Ying Ying , Xu Liang , Zhou Song , Wang Yan
Published: June 2012

Based on measurement data and the specific morphology of corrosion pit, three-dimensional finite element model of the corrosion damage specimen is established. Then the local stress condition of corrosion pits is given making use of finite element method, the results of stress concentration due to corrosion pits are also obtained, we can compare the stress concentration arised from the corrosion pit on aluminum alloy specimens in different corrosion time. Results show that the corrosion pits produce stress concentration and become the source of fatigue crack initiation and propagation. With the increasing of corrosion time, the pits get deeper and deeper, and the stress concentration gets more serious near the pits.
Influence of Microstructure and Precipitates on the Mechanical Properties of High Strength Hot Strip
Authors: Ma Jia Yan , Liang Wen , Guan Yun , Deng Zhao Jun
Published: June 2012

The relation between the microstructure, precipitates and the longitudinal mechanical properties of high strength hot strip was studied by optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The results showed that the yield strengths of the coil outer and middle parts were higher than that of inner part by 65MPa, and the tensile strength of the coil outer part was higher than that of middle part and inner part by about 50MPa. The number of subgrain with small size and that of dispersion distribution precipitates less than 30nm in outer part and middle part were more than that in inner part, which resulted that subgrain and precipitation strengthening were larger than that of inner part. For the coil inner part, the strengthening effects were made of fine-grained strengthening and M/A islands strengthening. The contribution of subgrain and precipitation strengthening to intensity is larger than that of fine-grained strengthening, which is the main reason causing the outer and middle parts having higher yield strength. The least tensile strength of middle part is related to the many blocky ferrites.
The Flow Stress Feature and Constitutive Equation of 6016 Aluminum Alloy during Hot Compression
Authors: Zhang Ji Xiang , Feng Wei , Wen Hui , An Guo Yin
Published: June 2012

The flow stress behavior of 6016 aluminum alloy was investigated on the condition of temperature range from 420°C to 540°C and strain rate range from 0.001s-1 to 1s-1 based on hot compression experiment on Gleeble-1500 thermal simulation machine. The result shows that the flow stress of 6016 aluminum alloy decreases with the enhancement of temperature and increases with the increase of strain rate. Especially, the flow stress increases tendency becomes obvious when the strain rate greater than 0.1s-1. Based on the results above, a constitutive equation for flow stress of 6016 aluminum alloy when the temperature is above 420°C is obtained by linear regression.
Fatigue Behavior of A5052 Aluminum Alloy with DLC/Thermally Sprayed WC-12Co Hybrid Coatings
Authors: Uematsu Y. , Kakiuchi T. , Kobayashi Y. , Harada Y.
Published: June 2012

Rotating bending fatigue tests had been performed using A5052 aluminum (Al) alloy with the hybrid coatings which consisted of tungsten carbide including 12% cobalt (WC-12Co) interlayer and diamond-like carbon (DLC) film, in order to investigate the effect of hybrid coating on the fatigue behavior. The WC-12Co layer was thermally sprayed by a high velocity oxygen fuel (HVOF) method on A5052 with the thickness of 70, 120 or 170μm. Subsequently, the DLC film was deposited with the thickness of 15μm. The fatigue strengths of the specimens with WC-12Co single layer were higher than those of the substrate and increased with increasing the thickness of WC-12Co layer. The fatigue strengths of the specimens with the hybrid coating of 70μm WC-12Co interlayer and 15μm DLC film were better than those of the specimen with 70μm WC-12Co single layer. Thus the hybrid coating structure was effective to improve fatigue strengths. However the beneficial effect of hybrid coating was not apparent in the specimens with thicker WC-12Co interlayer of 120 and 170μm.
Influence of Blank-Holder Force on Springback of Cap-Shape Parts Bending
Authors: Su Chun Jian , Miao Shuang Shuang , Xiao Lin Jing , Guo Su Min , Gao Li
Published: June 2012

Springback is the prominent problem in bending forming of sheet metal, which is difficult to control accurately, especially for the complex shaped bending parts. The change of blank-holder force will cause significant changes of bending springback amount. The theoretical analytical model of cap-shape parts bending, which takes into account of the harden ability, anisotropy and elastic deformation of material, is proposed in this paper based on the plane deformation assumption and the bending theory of sheet metal, the cap-shape parts bending of wide sheet is analyzed theoretically, the approximate calculation relational expression is derived between the blank-holder force and springback angle, and the influence of blank-holder force on springback is discussed. In the same conditions, the springback result deduced from theoretical formula is basically consistent with numerical simulation and experiment result.
An Advanced Damage Propagation Model of Brittle Fracture
Authors: Du Chun Zhi , Qiu Wen Yan
Published: June 2012

To reduce the coal mining risk, drainage of methane with drills and hydraulic fracture has been put in practice. In the paper, an advanced damage propagation model of brittle fracture is studied based on mode I crack. The localization band of damage is inducted, and the modal of localization of damage around crack-tip is established using fracture and damage mechanics. Besides, the stress distribution in localization of damage is assumed as obeying a quadratic function, thus the stress field around the crack is obtained, and the calculation formula of crack length is presented, which can provide reference for mine production.
Research on the Cold Rolling Mechanical Character of Low Carbon Base Plate Produced by CSP
Authors: Wang Su Fen , Peng Yan , Li Zhi Jie , Liu Yun Fei
Published: June 2012

With cold rolling base plate of low carbon steel by CSP process, the cold deformation experiments were carried out by the two-roller reverse-mill in the laboratory. The work-hardening was studied for different deformation plates through the room temperature tensile and microhardness measured, and the microstructure was also studied after deformation. It was found that the steel yield and tensile strength increased and work-hardening marked with the deformation augment, the test steel microstructure is ferrite with mingle small amount pearlite, its grain is refined and elongated with deformation increasing.
Structural Behavior of a New GSZ Panel under Lateral Loads
Authors: Huang Qun Yi , Xiong Feng , Ge Qi , Yin Yan , Zhou Ning
Published: June 2012

Results of an experimental investigation to study the structural behavior of new GSZ panels are reported. Three half-scale new GSZ panels with variable reinforcement ratio were cast and tested under vertical loading and low cycle reversed horizontal loading. The failure process, strains in vertical steel bars and surface–concrete, load–displacement curve under increasing load were recorded and analyzed. Result obtained showed that the entirety performance of new GSZ panel is excellent. And the reinforcement ratio has a great influence on the lateral stiffness of the panel.
Inspection and Evaluation of Load-Bearing Capacity of Single Tower Composite Girder Cable-Stayed Bridge
Authors: Zhang Xie Dong , Wang Jin Zhi , Guo Jun Feng
Published: June 2012

In order to evaluate single tower composite girder Cable Bridge actual bearing capacity and working property on design using load, a single-tower composite girder cable-stayed bridge is taken as an example, by means of static load test, dynamic load test, reasonably measures evaluates the single tower composite girder cable-stayed bridge's bearing capacity. The static load test measure static properties of bridge structure (static strain, static deflection, etc.), dynamic load test, measure the dynamic properties of bridge structure (vibration frequency, damping, forced vibration amplitude, impact coefficient, etc.). Results show that the rigidity strength integrity and dynamic characteristics of bridge structure are favorable; the structure’s bearing capacity is favorable.
Calculation on Modal Damping Ratio of Stay Cable Using Nonlinear Friction Damper
Authors: Wang Hui Ping
Published: June 2012

Stay cables of long span cable-stayed bridges are easy to vibrate under wind or wind/rain loads owning to their very low inherent damping. To install cable dampers near to the anchorages of cable has become a common practice for cable vibration control of cable-stayed bridge structures. In this study, the behaviors of a nonlinear frictional type of damper were investigated. The equations of motion of a cable with a friction damper were derived by using a lumped mass model. Then by introducing modal transformation, the analytical solution for the motion equations was obtained. The results show that the friction damper evokes linearly decaying of free vibrations of the cable as long as the damper does not lock the cable. The modal damping ratio of cable with the friction damper is strongly amplitude dependent. Calculation of modal damping ratio can be simplified using control parameter and the maximum modal damping ratio can be obtained. A universal estimation curve is proposed that is similar to linear viscous damper. These studies could provide design basis for the vibration mitigation of stay cables using nonlinear friction.
Tribological Properties of Ni-Base Alloy Coatings Reinforced by SiC Particles
Authors: Xu Ting , Tan Ye Fa , Liu Bin
Published: June 2012

Ni-Co/SiC composite coatings embedded with different sizes of micron-Sic particles were prepared on the surfure of 45 carbon steel through electrochemical deposition. The effects of size of SiC particles on the microstructure, the hardness and tribological properties of the composite coatings were investigated. The results show that the decrease of the size may increase the hardness, make microstructure closer and greatly improve their wear resistance. The Ni-Co/SiC(W7) coating exhibit better integrated properties, its hardness was HV505, 20 percent higher than Ni-Co alloy coating, and its wear rate was only 1/5 of the Ni-Co/SiC(W40) coating. The wear mechanisms of the coatings are mainly plastic deformation with slight adhesive wear.
Study on the Experiment Laser Cladding and Shock Processing TC4 Titanium Alloy
Authors: Wang Cheng , Zhou Lei , Lai Zhi Lin , An Zhi Bin , Zhou Liu Cheng
Published: June 2012

In order to study the application of laser cladding and laser shock processing (LSP) combinatorial treatment technology, the laser cladding samples of TC4 titanium alloy was shocked by pulse laser, then the surface residual stress, the fatigue life were compared with those without LSP in this paper. High cycle tension-compression fatigue tests were carried out in laser cladding titanium alloy before and after LSP treated. The results indicate that LSP treatment can improve the high cycle fatigue endurance limit of laser cladding titanium alloy effectively. The nano-crystal grained surface layer with residual compressive stress makes great contributions to the improvement in fatigue properties of titanium alloy.
The Influence of Input Variability on the Compressive Residual Stresses in 30CrMnSiNi2A via Laser Shock Processing
Authors: Wu Yong Hua
Published: June 2012

The laser shock processing(LSP) is a new surface treatment technique that induce a significant compressive residual stress field on the metal and alloys. The developed compressive stress field is beneficial to improve surface properties such as fatigue, wear, and corrosion. To improve the understanding of the shock process, investigation into the physical processes and its variability involved is necessary. This work examines the effect of LSP at different input variability to induce its compressive stress. Various factors that affect the compressive stress of the LSP are tested with a serial experimental using 30CrMnSiNi2A as workpiece. It was found that the in-depth residual stress induced by LSP were a function of laser power density,laser beam spot size, laser pulse width and pulse repetition.
Laser Cladding of Iron-Based Self-Fluxing Alloy and its Application in Remanufacturing of Die-Casting Plunger
Authors: Tong Xin , Dai Ming Jiang , Liu Min
Published: June 2012

Die-casting plunger often fails due to serious wear on its cylindrical surface. The scrap of plunger used in large die-casting machine results in waste of materials and energy sources, and it is also against environmental protection. Therefore, the laser remanufacturing of die-casting plunger was studied in this paper. Both of the size and the performance of plungers were repaired by laser cladding surface modification using an iron-based self-fluxing alloy. The interface between original failed plunger and laser cladding layer showed a good metallurgical bond. The average thickness of laser cladding layer was 0.845 mm, and the average micro-hardness reached to 750 HV upwards. Microstructure in laser cladding layer was composed by the dendrite primary phase and the ledeburite organization. Iron (Fe), Chromium (Cr) and Molybdenum (Mo) elements were the main chemical compositions measured in laser cladding layer. The service life of laser remanufacturing plunger was nearly the same as the life of new plunger. However, its remanufacturing cost was only 50% of the new plunger’s. The laser remanufacturing technique is worth for extending and applying due to high cost performance.
GaAs-Based High Power Diode Laser
Authors: Gu Yuan Yuan , Wu Guo Xing , Lu Hui , Cui Yan
Published: June 2012

High-power diode lasers based on GaAs semiconductor bars are well established as reliable and highly efficient laser sources. The device structure and stack technology of edge-emitting diode laser were presented briefly as well as the development of electro-optical conversion efficiency ,lifetime , power .The technology of ten-thousand –watt level high power diode laser was introduced as a new generation of laser processing equipment. In order to output high power, we utilized polarization coupling technology to couple two 808nm and 880nm laser diode stack together, and designed the optical system to expand and focus the beam, through the experiment; we realize the overall efficiency more than 90%, power output 1000W.
Study on Numerical Simulation of Laser Quenching Based on ANSYS
Authors: Wang Jian Lai , Cao Jian , Lin Qian Kai , Feng Hui , Shen Hai Hua
Published: June 2012

In this paper, a temperature field model of 45 steel shafts during the laser quenching was built and simulated by using ANSYS software. Its surface temperature distribution of the shaft during the laser beams scanning was simulated. Their effects of different laser power, laser beams spot size and scan speed on part’s quenching performance were analyzed.
Mechanism of Healing Fatigue Damage by Pulsed Laser Surface Irradiation for Polycrystalline Copper Film
Authors: Ren Chong Gang , Shang De Guang , Nai Chang Gang , Wang Lu , Chen Tao
Published: June 2012

The mechanism of healing fatigue damage was investigated by pulsed laser surface irradiation for polycrystalline copper film, X-ray Diffraction(XRD), optical microscopic and scanning electron microscopy(SEM). The results indicate that surface melting and grain refinement were found in the melted surface layer. Tensile residual stresses were introduced in the resolidified surface layer due to laser surface melting which produced deleterious effect on fatigue property. Remelting and grain refinement in the surface layer is mainly responsible for healing fatigue damage and fatigue life improvement. The fatigue damage could be healed completely or partly by laser surface irradiation under the proper parameters of laser treatment for the specimens.
The Development of the Scaling 1:5 Friction Material Dynamometer Based on the Similarity Principle
Authors: Wang Zhen Yu , Wang Tie Shan , Yang Bin
Published: June 2012

There is more difference in the test data of the friction and wear for friction material between the small sample tester and dynamometer, because of the different structure and function. In order to improve the comparability, a kind of new scaling 1:5 for JF122SB dynamometer for the scaling testing based on the parameters of the scaling 1:1 for JF122 dynamometer was developed, according to the similarity principle. In this paper, it is show that the designing principle, the zoom scale, the main parameter and structure of the 1:5 dynamometer. Adopting the same testing standard SAEJ2681, the comparative trial has been done. Analyzing those test data it is proved that there are fine comparability and consistency between the two testers.
Transient Temperature Field Analysis in Laser Cladding Processing
Authors: Zhang Shuai , Tian Yan Ling , Wang Fu Jun
Published: June 2012

A 3-dimensional (3D) thermal distribution computational methodology for laser cladding is presented. Based on the developed model, which considers the latent heat and change of conductivity in different phase, the transient temperature fields for the preplaced laser cladding processing are performed. The effect of processing parameters including laser power, scanning speed and laser spot diameter on melt pool temperature filed was extensively discussed and some conclusions were drawn.
Finite Element Simulation Modelling for Laser Irradiated Bending Process of DP980 Steel
Authors: Song Jung Han , Lee Jong Sup , Lee Geun An , Park Sung Jun
Published: June 2012

Laser forming involves heating sheet metal workpiece along a certain path with a defocused laser beam directed irradiate to the surface. During laser forming, a transient temperature fields is caused by the irradiation and travelling of a laser beam. Consequently, thermal expansion and contraction take place, and allows the thermal-mechanical forming of complex shapes. This is a new manufacturing technique that forming metal sheet only by thermal stress. Therefore, the analysis of temperature fields and stress fields are very useful for studying the forming mechanism and controlling the accuracy of laser forming. The non-liner finite element solver, ABAQUS, is employed to solve the thermal-mechanical analysis. Using this model, the temperature and stress distribution of DP980 are analyzed. Numerical results agree well with the experimental results.
Analysis of Thermal Elasto-Plastic Stress during Pulsed Laser Heating a K418 Alloy Plate
Authors: Lu Chang Liang , Hu Fang You , Huang Xu Ren , Yi De Xian , Cui Ai Yong , Hu Bin
Published: June 2012

The paper presents a study on analysis of thermal elasto-plastic stress during pulsed laser heating a K418 alloy plate. Based on elasto-plastic constitutive relationship, a spatial finite element model was established to simulate the whole process. The distribution and evolutions of temperature and stress field was calculated. The stresses induced during the process are highly heterogeneous because of the recurrent changing temperature field. The stresses during the process fluctuate as the temperature field changes. High level tensile residual stresses reside in the fusion zone after the laser process. Compared to all other stress components, longitudinal stress is the highest and will have considerable influences over the distortion level and failure of the material.
Research of the Nonlinear 3D Surface NC Machining Technology
Authors: Liu Hong Jun , Huang Jie , Zhi Shu Ya
Published: June 2012

Discuss a way of using the CAD/ CAM technology to process nonlinear space surface. By analyzing the processing of nonlinear space surface, the nonlinear space surface machining process plan was determined. The fine model and program was finished by innovative using of combination modeling method in UG. Many key technical problems such as surface finish, work fixture were solved in the process of dealing with CAD/CAM of nonlinear space surface, acceptable product was made on common milling machine by using post-processing NC coding,. The process plan improved machining precision and shortened the production cycle，a good results have been obtained.
Effect of Ultrasonic Vibration on the Friction and Wear Properties of GCr15/45# Steel Frictional Pairs Lubricated by n-Al2O3 Additives
Authors: Qiao Yu Lin , Yang Shan Lin , Zang Yan , Dong Xin Yu , Cui Qing Sheng
Published: June 2012

The friction and wear properties of GCr15/45# steel frictional pairs lubricated by n- Al2O3 additives under ultrasonic vibration or not were studied. The scanning electron microscope(SEM), X-ray photoelectron spectroscopy(XPS) and energy dispersive spectrometer (EDS) were carried out to analyse the wear scar surface. The effect mechanism of ultrasonic vibration on friction pairs was discussed. The results indicated that ultrasonic vibration could decrease the friction and wear of GCr15/45# friction pairs, when the content of n-Al2O3 was 0.5wt%, the effect of ultrasonic vibration on friction pairs was most obvious. The friction coefficient, wear volume and wear scar depth under ultrasonic vibration decreased 10%, 34% and 13%, respectively. The friction reduction and anti-wear mechanism of n-Al2O3 was single “micro ball bearing” without ultrasonic vibration, and it changed to “micro ball bearing” and adsorption penetration film with ultrasonic vibration, so the friction coefficient and wear volume was reduced.
Finite Element Analysis of Multi-Ropes Friction Hoister Main Shaft
Authors: Yan Ming Xia
Published: June 2012

Three-dimensional model of the main shaft of JKM4×4 hoister was built based on Pro/E. After having applied boundary conditions and loads to the model, the finite element analysis for the main shaft was conducted under extreme operation conditions with ANSYS, the stress and displacement distribution was presented and the stress biggest hazard points were found. Based on the analysis results, improvement methods for the main shaft structure design was given out, which provides references for further optimal designing the main shaft of hoister.
Influence of Different Viscosity Lubricant to Finite Line Contacts on Elastohydrodynamic Lubrication (EHL) under Oscillating
Authors: Wang Yan Fei , Hua Tong Shu , Sun Hao Yang
Published: June 2012

To make further researches into the elastohydrodynamic lubrication properties of a finite line contact roller, oscillating experiments were carried out on made overload experimental rig for oil film measurement using optical interference technique. Film thickness and shape were measured in two kinds of viscosity polyisobutylene. This study indicates that both lubricant viscosity and roller entrainment velocity play an important role on EHL of finite line contacts. On motion, the more increase in viscosity or speed, the thicker the oil film thickness, simultaneity edge effect is distinctly intensified and film thickness increases less on roller end, difference of the film thickness is increased between roller end and the central. Above two parameters are significant for logarithmic profile roller in crowning design.
Research on a Novel Process of Subway Synthetic Brake Shoe
Authors: Yang Cheng Mei
Published: June 2012

In this paper, taking Chinese Nanjing Metro ALSTOM vehicle synthesis brake as an example, the subway with synthetic brake shoe for composition analysis, comparative study of multiple forming process, eventually developed to hybrid fiber as reinforcing material, modified phenolic resin as matrix material, and then filling friction modifier performance, using direct molding the mixture of dry moulding process made new domestic subway brake shoe. The product of the test performance indicators that can replace the similar foreign products.
Fault Diagnosis Method for the Rolling Bearing Based on Information Fusion and BP Neural Network
Authors: Zhang Jin Min , Huang Yin Hua , Wang Si Ming
Published: June 2012

Abstract. In order to diagnose the fault of rolling bearing by the vibration signal, a new method of fault diagnosis based on weighted fusion and BP (Back Propagation) neural network was put forward. At first, the vibration signal from the sensors was wave filtered through the method of correlation function, then the fused signal was obtained by the classical adaptive weighted fusion method, the multi-type characteristics parameters was to be as a neural network input. Finally, the fault diagnosis of rolling bearing was realized by the BP neural network, and the results show that the multi-sensor information fusion fault diagnosis method can be proved effectively to achieve the fault diagnosis of rolling bearing.
The Analysis of the Deformation and Contact Lubrication Problem of HPD Diesel Engine Piston Pin Bearing Based on the FFT Method
Authors: Zhang Jun Yan , Han Shu Kui
Published: June 2012

Based on the unified Reynolds equation model and fast Fourier transform (FFT) method, the lubrication performance of the piston pin bearing for high power density diesel engine was studied by numerical simulation. First of all, through the coupled solving of a unified Reynolds equation and elastic deformation equation, the influence of the viscous-pressure effect on the maximum film pressure and the minimum oil film thickness for piston pin bearing are investigated. The results show that, after considering the viscosity-pressure effect, the minimum oil film thickness and the maximum film pressure of semi-floating piston pin bearings for high power density increase, and the elastic deformation decreases in greatest load position. It confirms that the bearing capability is greatly enhanced while the viscosity- pressure effect is considered. Secondly, The eccentricity ratio of the piston pin bearing in vertical direction of the piston stroke is smaller, however it is much larger in the downward direction of the piston stroke, which indicate that the below area of the piston pin bearing bears greater load and occurs larger deformation. This is consistent with the reality that the below area of the piston pin bearing is prone to damage and wear
Reliability Sensitivity Analyses for Oil Whip in Rotor-Bearing System
Authors: Su Chang Qing , Sun Yi Yu , Li Le Xin
Published: June 2012

Oil whip phenomenon is the common fault in rotor-bearing system. The reason why oil whip happens often has been researched in high-speed rotor-bearing system. But in practice engineering, due to the requirement of work condition, oil whip cannot be avoided all the time in rotor-bearing system. The paper is based on the relation criterion of oil whip happens in rotor-bearing system, the reliability mode and system reliability of oil whip are defined, and the reliability analysis method for avoiding oil whip in rotor-bearing system is carried out. The effect on reliability sensitivity of random parameters is studied. Numerical results are also presented and discussed.
Producing Mechanism on Flow Regeneration Noise from Muffler Element with Inserted Tube
Authors: Zhao Hai Jun , Chang Jia Dong , Wang Hai Xia , Li Qi
Published: June 2012

Structure parameters of muffler element with inserted tube are firstly determined, it is analyzed to the inserted length effecting on sound power of flow regeneration noise and frequency characteristic, and distribution feature of flow velocity and turbulence kinetic energy is explored by numerical computation of flow field. It is shown that flow regeneration noise of muffler element with inserted tube forms according to confined incomplete flow-inject, it presents wide frequency band, and its energy focus on middle and low frequency, especially it is about 600Hz, Strouhal Number is 0.5. When its structure parameters is constant, distribution feature of flow velocity and turbulence kinetic energy doesn’t change with flow velocity, and difference is numerical dimension, and turbulence kinetic energy distributes near inserted tube in wall, this is area occurring flow regeneration noise, so producing mechanism of flow regeneration noise from muffler element with inserted tube is achieved.
Optimization of the Heat Sink for the Power Component by Taguchi Method
Authors: Li Nan , Fu Gui Cui , Pei Chun , Zhang Dong
Published: June 2012

With the development of manufacture technology, it is a critical problem for the reliability of avionic devices that components have to operate at high heat flux. And the package of components cannot meet the requirements of the heat dissipation. Therefore, it is essential to add heat sink on the top of power components. This paper presents the use of Taguchi method in optimizing the heat sink. The heat sink is designed to balance the weight and the temperate distribution of the component. At first, several parameters of the heat sink, including the base width, the base length, the fin height, the fin number, are chosen to be controllable factors. The machining errors are the uncontrollable factors. Then, four orthogonal arrays are used to lead the design of experiments (DOE). Finite-volume method (FVM) is used to calculate the case temperature of the component. Basing on the results generated by the Taguchi DOE method, the optimal design of heat sink can be chosen. Additionally, the heat sink can be optimized, while the reliability of component and device can be improved by using this method.