bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on Sequential Compliance Method Influenced by Shape Parameter of Weibull Distribution
Authors: Lou Hong Liang , Li Xing Lin , Xu Xian Zhao , Zhang Yang Ping , Yu Zhong Hua
Published: February 2011

When sequential compliance method is used for Weibull distributions, the shape parameter is usually considered to be fixed. However, because of the life of products are determined by many factors, the shape parameter is variational in practice, that is to say, the shape parameter in the criterions is different from that in the practice. In this paper, the changes of acceptance and rejection probability are researched by the influence of shape parameter changes. Finally, by means of simulation test, changes on the shape parameter affecting on the probability of acceptance and rejection are quantitatively analyzed. As a result, the larger the gap on the shape parameter in the criterions and in the practice is, the larger the gap on the producer’s risk and the consumer’s risk.
Development and Trend of Ultrasonic Techniques in On-Line Detection for Strip and Plate’s Internal Defects
Authors: Cui Feng Kui , Zhang Wen Hu , Liu Jian Ting , Zhang Feng Shou
Published: February 2011

For meeting the requirements of high-precision and high-speed in on-line detection for strip and plate’s internal defects, in the paper, based on elaborating methods and principle of conventional ultrasonic testing, the research status of traditional ultrasonic testing technology and non-contact ultrasonic testing techniques, there analysis and discuss the problems and causes in the process of detection. In the end, the trend of development is given.
Characteristics of In-Ge-Sb-Sn-Te Thin Film Used for Phase Change Optical Recording Media
Authors: Ou Sin Liang , Cheng Chin Pao , Yeh Chin Yen , Chung Chung Jen , Kao Kuo Sheng , Lin Re Ching
Published: February 2011

The In10GexSb52-xSn23Te15 films (x = 2, 5, and 9) were deposited on nature oxidized silicon wafer and glass substrate by dc magnetron sputtering. The ZnS-SiO2 films were used as protective layers. The thickness of the In10GexSb52-xSn23Te15 film is 20 nm. We have studied the crystallization kinetics, structural and optical properties of the In10GexSb52-xSn23Te15 (x = 2, 5, and 9) recording films. It is found that the crystallization temperature of the film is increased with increasing Ge content. The optical contrasts of In10GexSb52-xSn23Te15 films with x = 2~9 are all higher than 30 % at a wavelength of 405 nm, showing that the films are suitable for blue laser optical recording media application.
Fabrication of SiCp/ZL101 Composites Substrate with Near-Net-Shape
Authors: Zhou Xian Liang , Zou Ai Hua , Hua Xiao Zhen , Li Duo Sheng , Ye Zhi Guo
Published: February 2011

SiCp/Z101 composites substrate can be successfully fabricated by pressureless infiltration of ZL101 alloy liquid into porous SiCp preform, the relative density are nearly up to 99%. This is mainly because that generated SiO2phase on the surface after sintering of SiCp not only has joint function to the porous of SiC perform, but also obtains two-phase wetting between SiC and Al matrix through the interface reaction, resulting in promoting spontaneous infiltration. SiC preforms have almost no change of shapes and sizes after infiltration of Al liquid and can achieve near-net-shape of the composites for substrate. Volume fraction of SiC can be effectively improved by using binary mixture particles with the diameter ratio of 11:1, through which the properties of substrate can be controlled effctively. By the addition of SiCp, strength of the composites is improved remarkably, and its elastic modulus increases correspondingly about one time, the increase of SiC volume fraction can markedly reduce coefficient of thermal expansion (CTE) of composites , but meanwhile decrease thermal conductivity(TC) of composites, and its TC (at 50 °C ranges from 120.7 W/(m•k) to 99.4 W/(m•k) and its mean linear CTE (25°C to 50°C ) ranges from 9.47×10−6k-1to 7.05×10−6k-1as volume fraction of SiC ranges from 38% to 68%.
Preparation and Properties of Electroless Deposited Ni-Sn-P Ternary Alloy Coatings
Authors: Zhu Shao Feng , Wu Yu Cheng
Published: February 2011

In this paper, Ni-Sn-P ternary alloy coating was prepared by the electroless depositing technique. Effects of tannic chloride, reductant and pH value of the bath on the coating were studied. And, erosion behavior of the coating in the 3.5g dm-1sodium chloride solution was also investigated. The results show that the electroless deposited Ni-Sn-P ternary alloy is amorphous. The deposition rate and the tin content in the coating increase, but the phosphorus content in the coating decreases with increasing the stannic chloride and sodium hypophosphite contents in the bath. The deposition rate increases with the pH value of the bath in the range of 3 to 6. Mass loss of the coating increases with increasing the erosion time and the flow velocity of erosion solution, which has its maximum value as the coating impacted at an angle of 60°.
Realization of the Closed Cycle Diesel Control System
Authors: Liu Xiao Song , Zhang Xin Yu
Published: February 2011

The exhaust gas produced by the diesel engine is reclaimed to the mixing chamber where it was mixed with pure oxygen and argon. The mixture which forms "artificial air" will be used as the diesel intake to achieve the diesel engine’s working in closed cycle. The most critical part in closed cycle diesel engine control system is to control the oxygen concentration and specific heat of the intake. This paper is based on the design of GE9030-based PLC and the monitoring interface used in this paper is designed by KingView6.53, finally, the control of specific heat of the intake, concentration of the oxygen intake and pressure of the intake are realized. Moreover, real-time displaying, gathering and fault alarm of the operating parameters in this system are achieved.
Slip Fascia Stiffness Effect to the Fifth Metatarsal Movement during Inversion Landing
Authors: Gu Yao Dong , Ren Xue Jun , Li Zhi Yong , Ruan Guo Qing , Yang Li
Published: February 2011

Injuries of the base of the fifth metatarsal are among the most common of all skeletal injuries of the foot. The fracture is considered by previous research to be an avulsion due to the slip fascia, however, the mechanism of the plantar slip fascia’s function still not very clear. In this study, a detailed three-dimensional (3D) finite element (FE) model was developed by reconstruction of CT images. A sensitivity study was conducted to evaluate the effect of varying stiffness of the slip fascia on the fifth metatarsal’s deformation. The results showed that the largest vertical displacement was appeared in the metatarsal’s head part, and the difference was up to 10.5%, while the Young’s modulus of the slip fascia increasing from 50MPa to 500MPa.
Preparation and Properties of Weldable Self-Cleaning PVDF/PVC Blended Film
Authors: Zheng Zhen Rong , Gu Zhen Ya , Huo Rui Ting , Yu Wan Cheng
Published: February 2011

PVDF was blended with PVC to improve the weldable property of PVDF topcoat. Effects of film formation process on the surface properties of PVDF/PVC blended film were investigated. Peeling strength of PVDF/PVC blended film has reached the internationally accepted standards (144.3N/5cm) when PVC concentration was 30%. Based on the “lotus effect” principle, PVDF/PVC film was hydrophilic modified by alkali solution and then grafted with alkyl chlorosilane to fabricate the micro- and nano-structures as the surface of lotus leaf. After grafting, contact angle of PVDF/PVC blended film was as high as 152.8°, and self-cleaning test showed dusts on this film surface can be easily taken away by water droplet when PVDF/PVC blended film was titled less than 1°.
Analysis on the Anodic Oxide Film of Aluminum Pistons Formed in High Current Density and Wide Temperature Range
Authors: An Jia Ju
Published: February 2011

A process in anodic oxidation with high current density and wide temperature range was researched for high speed forming film on the top surface of aluminum piston. The oxidation parameters is a concentration of 18% H2SO4 solution-based liquid, current density of 5.5～8A/dm2, temperature range－5～20°С , the oxidation time for the 0～60min. Pulse power and cooling equipment co-work to produce the film thickness up to 107μm, film speed was about 1.78μm / min. SEM indicates that the porous layer was made of the regular array columnar “cells” which parallel arrange and grow perpendicular to substrate.
Surface Characterization of Chinese Fir/TiO2 Composite
Authors: Huang Su Yong , Li Kai Fu
Published: February 2011

Small samples of Chinese fir/TiO2 composites were prepared by sol-gel method and MWLPD (microwave assistant liquid phase deposition) method for the first time. The surface of samples were analyzed by Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS), and the microstructure and Ti distribution of samples was observed by scanning electron microscopy and energy dispersive spectroscopy (SEM-EDS). Results show that Ti is not only distributed on the composites surface, but also go into the inside wood. The composites surfaces are covered with pure TiO2. Activities of composites are increased considerably for the oxygen content and number of oxygen containing groups on there surfaces are increased considerably.
Comparison of Surface Roughness Measurement in Dichromatic Speckle Patterns with Autocorrelation Method
Authors: Yuan Zong Heng , Zhang Yan Hua , Zhang Jian Wei , Ge Ye Fan
Published: February 2011

Applying autocorrelation method to process laser speckle patterns, the relation between surface roughness and speckle elongation and correlation length of autocorrelation function can be obtained, and the measured surface roughness can be achieved based on this relation. One-dimension autocorrelation and two-dimension autocorrelation function are used, Moreover, surface roughness is evaluated by speckle elongation and correlation length of autocorrelation function. Aspect ratio of speckle granular represents speckle elongation ratio, which eliminates effects of speckle granular average size on measurement results compared to other methods using before. It has high reliability and efficiency in surface roughness measurement evaluation.
Influence of Electric Field Interference on Three Nozzles Electrospinning
Authors: Yang En Long , Shi Jing Jing
Published: February 2011

The low production rate of electrospinning process may limit the industrial use of single needle system. To meet high yield requirement and uniform fibers, a bottom-up multiple jets electrospinning nozzle was designed. The influence of electric field interference on jet path, membrane shape and fiber morphology was investigated. Experiment finds that electrical field strength in the closer part of two nozzles is weakened due to electric field interference when the distance between two nozzles is close. Electric field, jet path, fiber web shape and fiber morphology of three nozzles electrospinning with linear arrangement, equilateral triangle arrangement and isosceles right triangle arrangement were also compared. Results show that electric field and spun fibers of three nozzles electrospinning with equilateral triangle arrangement is the most uniform.
The Research about Oxidation Kinetics of Ti60 Alloy and Ni-Co-Cr-Al-Y-Si Coating on Surface
Authors: Li Jian Feng , Guo Li Zhi , Li Guo Qing
Published: February 2011

This article summarized depositing craft of the superficial coatings (Ni-Co-Cr-Al-Y-Si) on the Ti60 alloy (Ti-6.5Al-4.2Sn-4Zr-0.6Si) with arc ion plating technology and the oxidation behavior under 600~750 . The X-ray diffraction (XRD) and the scanning electronic microscope (SEM) were used to analyze the surface appearance, the structure and the ingredient conducts of non-coating Ti60 alloy. The contrast shows that the coatings have good protection to Ti60 alloy. The result indicated that the coating has the good oxidation resistance performance under 600°C , 650°C and 750°C . Coated Ti60 alloy oxidation resistance is markly improved. The circulation oxidation dynamics curve basically conforms to the parabola rule.
Enhancement of the Service Lifetime of TiN Coated Punch Side pin by Adding a Small Amount of Yttrium
Authors: Yu Zhi Ming , Niu Yun Song
Published: February 2011

The Ti(Y)N coatings were successfully deposited onto 18-8 stainless steel substrates by the hollow cathode discharge (HCD) ion-plating method through the application of a Ti-Y(0.2 wt%) alloy evaporation source instead of pure titanium. The influence of Y on the adhesion of the TiN coating/substrate was studied. The results show that the adhesion of the coating to the substrate was evidently enhanced by adding a small amount of the rare-earth element yttrium. The Ti(Y)N coatings deposited on some punch side pins were presented and compared with the TiN coating. The service lifetime of Ti(Y)N coated the punch side pin is approximately 50% higher compared to that of TiN coated.
Effect of Pre-Shot Peening on the Fretting Fatigue Behavior of Plasma Nitrided AISI 420 Stainless Steel at 350 °C
Authors: Tang Jin Gang , Liu Dao Xin , Xi Yun Tao , Zhang Xiao Hua
Published: February 2011

AISI 420 martensite stainless steel was plasma nitrided with/without shot peening (SP) previously at 350 °C. The FF resistance of researched material was evaluated using a rotating bending fatigue machine and a home-made apparatus. The results indicated that low-temperature nitriding alone and the combined treatment both improved the FF resistance of AISI 420 stainless steel significantly. However, the later did not lead to higher FF resistance than the former. FF cracks tended to initiate at microcrack defects induced by SP.
Thermal Effects of Aluminum Nitride
Authors: Jheng Wern Dare , Chen Chien Chon , Chen Shao Hsien
Published: February 2011

The purpose of this study, using high vacuum sputtering machines, is to sputter multi-layer of aluminum nitride composite layer (AlNx) for the solar selective absorbing film. Using UV spectroscopy, gloss meter, thermometer, etc. to explore features of AlN under different wattage deposited composite layer (AlNx) . The study found that if the interference of light through the glass before exposure to the AlN compound layer (AlNx), the thermal rise rate than direct exposure to light to the composite layer of aluminum nitride (AlNx) significantly improved, its efficiency by up to 9 %
Anodic Aluminum Oxide Matrix Encapsulating Nonivamide for Anticorrosion and Antifouling Application
Authors: Qiu Ri , Wang Peng , Zhang Dun , Wang Yi
Published: February 2011

Electrochemical method is applied to prepare the porous anodic aluminum oxide (AAO) membrane. After the impregnation process, nonivamide was encapsulated into the channels of the AAO membrane. We apply the electrochemical impedance spectroscopy and polarization techniques to measure the performance of the combined material. The slight solubility of nonivamide enables it to release slowly from the AAO channels. This composite AAO-nonivamide material can show multifunctional effects, anticorrosion and antifouling, to the substrate aluminum metal.
Study on Structure and Properties of Alloy Nodular Cast Iron Roller with Laser Heat Treatment
Authors: Qin Cha , Hou Zhe Zhe , Zhu Hao , Zhang Yan , Zhao Qing Hua
Published: February 2011

The microstructure analysis and hardness test were carried out on the surface of alloy nodular cast iron roll treated with CO2 laser of power 5 KW by optical microscopy, Rockwell hardometer and micro-hardometer. The results indicate the cladded layers with laser heat treatment are divided into melt region, phase change region and substrate region. The dimension and microhardness for every region are related to laser power, scanning speed and process parameters. The fatigue life of alloy nodular cast iron roll treated with laser increased remarkably.
Microstructural Study of Nanostructured ZrO2 Based Thermal Barrier Coatings Fabricated by High Efficiency Supersonic Plasma Spraying
Authors: Bai Yu , Han Zhi Hai , Li Hong Qiang , Xu Chao , Xu Yan Li , Ding Chun Hua , Yang Jian Feng
Published: February 2011

In this paper, the microstructure of nanostructured zirconia (ZrO2) based coating fabricated by newly developed process, high efficiency supersonic atmospheric plasma spraying (SAPS), is studied. The velocity and surface temperature of in-flight particles during spraying were monitored by on-line system and the microstructure and phase composition of the as-sprayed coating was characterized with SEM, TEM and XRD. Meanwhile, the bonding strength between the top coating and bond coating was measured. The results showed the average in-flight velocity of YSZ particles in SAPS was about 430m/s, which was much higher than that of conventional atmospheric plasma spraying (APS). The as-sprayed coating was composed of well-adhered fine lamellar structures with thickness of 1-4μm. The desirable structure was attributed to higher impact velocity of in-flight particles during SAPS process, resulting in the improvement of flattening degree of molten particles. Meanwhile, the SAPS-YSZ coating exhibited a bimodal distribution with small grains (30-50nm) and large grains (60-110nm), the latter was the main microstructure of the coating. In addition, it was found that the monoclinic zirconia existing in the original powders transformed into tetragonal phase after plasma spraying and the bonding strength of as-sprayed coating was as high as 46±3MPa. The high efficiency supersonic plasma spray, which offers some unique advantages over the conventional plasma spraying process, is expected to be potentially used to deposit a wide variety of nanostructured coatings at lower cost.
Growth Process and Corrosion Resistance of Ceramic Coatings of Micro-Arc Oxidation on Mg-Nd Magnesium Alloys
Authors: Guo Yong Chun , Li Jian Ping , Li Jin Shan , Wang Ping
Published: February 2011

The regulation of ceramic coating formed by micro-arc oxidation on Mg-3Nd-0.2Zn-0.4Zr(wt%) magnesium alloys has been investigated by SEM and XRD. The relation of phase structure and corrosion resistance of MgO coating formed by micro-arc oxidation in different growth stages has been analyzed. The results have shown that in the initial stages of micro-arc oxidation, the growth of coating accords with linear regularity, which is the stage of anodic oxidation controlled by electrochemical polarization. With elongated treated time and increased thickness of the coating, the growth of coating accords with parabolic and linear regularity, which is the stage of micro-arc oxidation. In the stage of local arc light, the slope of parabola and thickness of loose coating increases so that the growth rate enhances. The phase structure of loose coating is mainly composed of MgSiO3 and the phase structure of compact ceramic coating is mainly composed of MgO. From the stage of micro-arc oxidation to local arc light, corrosion resistance of coating firstly increase and then decrease. The satisfied corrosion resistance corresponds to the coating time ranging from 7 to15minutes.The addition of rare earth elements in the magnesium alloy reduces the amount of smooth areas on ceramic surface. So the ceramic coating becomes more compact and smooth. The rare earth elements don’t form independent phases in ceramic coating but affect the relative proportion of constitution phases, resulting in the reduction of intermixed magnesium phase and the increase of the MgO and MgSiO3 phases.
Errosion-Corrosion Critical Performance of Surface Nanocrystalline 20 Carbon Steel in Condensate Water
Authors: Zhu Xiao Lei , Lu Xiao Feng , Ling Xiang
Published: February 2011

In this paper, the ultrasonic shot peening (USSP) technology was used to obtained surface nanocrystalline of 20 carbon steel. The grain size of test surface and the thickness of nanocrystallization layer were analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM). The three electrode electrochemical measurement was employed to investigate the electrochemical corrosion performance and the critical character of USSP surface nanocrystallization samples in different impact strength. The results showed that the USSP surface nanocrystallization could obtain the nanocrystalline grain. The thickness of nanocrystallization layer increased and grain sizes reduced with the increase of the impact strength. Nanocrystallization layer took the way to expand concentric circles with impact crater as the center. The corrosion current of nanocrystallization sample was much larger than as-received. The controlled step of corrosion process was turned from cathodic process to anodic process by USSP surface nanocrystallization. The sample surface formed two layers corrosion product films in condensate water, which were compact Fe3O4membrane as inner corrosion product film and loose Fe3O4membrane or Fe2O3membrane as outer layer. With the increase of the impact strength, critical velocity of the outer corrosion product film increased gradually. The critical velocity of inner corrosion product film had an increasing trend, but the critical velocity tended to be a constant value when impact strength was more than 1.9904min/cm2
Preparation of Fe-Cu-Ni-Mo-C Alloy with High Performance by Powder Metallurgy Warm Compaction
Authors: Huang Jun Sheng , Min Sheng
Published: February 2011

Fe-1.5Cu-1.5Ni-0.5Mo-0.3C alloy was prepared by powder metallurgy (P/M) warm compaction. Under the conditions of compaction pressures of 600 or 800 MPa and compaction temperature of 100 or 120°C , sintered in cracked ammonia atmosphere at 1120°C for half an hour, the researched alloy samples with higher properties could be prepared. The results show: when formed at a compaction pressure of 800 MPa and compaction temperature of 120°C , the alloy presented a sintered density 7.41g/cm3, hardness 88HRB, ultimate tensile strength 593MPa， yield strength 585MPa, and elongation 3.8%. Their mechanical properties, crack morphology and surface composition weres analyzed.
Properties of the Mortar Modified with the Styrene-Acrylic Emulsion
Authors: Zhang Shui , Li Guo Zhong , Ning Chao
Published: February 2011

Styrene-acrylic emulsion was selected to modify the cement mortar which was prepared as the crack mending material for the concrete pavement. The results indicated when the percentage of the styrene-acrylic emulsion was from 15% to 20%, the flexural strength and the bent bond strength increased by 39.00%~48.23% and 45.01%~49.60% respectively at 28 days, compared to the reference mortar. The morphology of the cement mortar modified with styrene-acrylic emulsion was observed by SEM. The modification mechanism of the styrene-acrylic emulsion to the mortar was discussed.
Experimental Study on Relationship between Saturation Degree and Void Ratio of Remolded Soils on Drying Path
Authors: Wang Dong Lin
Published: February 2011

By using of shrinkage curve, the empirical relationship between the degree of saturation and the void ratio on drying path was established for four types of soils including sand, silt, clay and soft clay. It was indicated that during the process of drying, the soil samples continuously shrunk with the decrease of saturation degree. For test samples of sand and silt, the curve of saturation degree and void ratio is flat; For test samples of clay and silt clay, however, the shrinkage of the soil samples was almost fulfilled when the degree of the saturation of soil samples decreased to 90% and the void ratio of the soil samples almost kept unchanged while the degree saturation of soil was reduced to 70%.
SEM and XRD Investigation on Mechanism of Expansion and High-Early-Strength of a Cementitious Composited Grouting Material
Authors: Sang Guo Chen , Zhang Hao Bo , Zhu Yi Yun
Published: February 2011

In this paper, an innovative research on mechanism of a non-shrinkage and high early strength composited cements-based grouting material is presented. A blend cements system of ordinary Portland cement (OPC), calcium aluminate cement (CAC) and calcium sulfate (CS) were used in the innovative grouting material. Through the systemic studies on the influence of the constituents on properties of the grouts and microstructural study by Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD), experimental results show that the development of the compressive strength and expansion ratio in hydrated cementitious grouts resulted from ettringite formation and quantity of ettringite crystals in the cementitious grouts.
Experimental Research on Performance of Anchorage of Planting Rebars with Inorganic Material in Concrete
Authors: Luan Huan Qiang
Published: February 2011

The application of planting bars technology in engineering strengthening and rebuilding is extensive. Contrary to organic material, inorganic material has advantages in high temperature resistance and long-term durability. Based on pull-out test of different diametrical rebars(12,14,16,20,22) with different anchorage length(10d,15d,20d) in concrete foundation of different strength(C20,C25,C30,C40).Factors affecting the ultimate bearing capacity of rebars are deduced. Fatherly the load-displacement curve is obtained. The result provides the basis for engineering application design. Its characteristics in early strength, adhesive force to concrete can satisfy the need of the building to the planting rebars with inorganic material and the loading force. Therefore it can be used as a substituting material for anchoring adhesive.
Determination of Tensile Strength of Compacted Loess by Double Punch Test
Authors: Li Xiao Jun , Liu Ying Ran , Jiang Li Hua , Tang Yi Chuan
Published: February 2011

Through double punch test, the tensile strength of compacted loess is determined under different water contents and different dry densities, the relationship between tensile strength, water content and the dry weight density is discussed, and their relationship is established. Comparing with Brazilian test, it proved the feasibility of determining tensile strength of compacted loess with double punch tests.
Effect of Solution Treatment Temperature on Microstructure and Mechanical Properties of Cr20Ni32AlTi Alloy
Authors: Yang Chang Chun , Kang Yong Lin , Qin Sheng , Wang Li Xin
Published: February 2011

The effect of solution treatment from 1050°C to 1200°C, soaking time 15min on microstructure, mechanical properties and precipitation behavior of Cr20Ni32AlTi alloy was investigated. The results are as follows: with the increasing of the solution treatment temperature from 1050°C to 1200°C, the average grain size increases remarkably from 17μm to 110μm, the strength of alloy decreases while the elongation increases. The amount of carbide precipitation in the alloy decreases with the increasing of solid solution temperature. The optimum solution treatment temperature for the investigated Cr20Ni32AlTi alloy is 1150°C~1200°C.
Effect of Composition and Temperature on the Formation of Delta Ferrite in the Billet for P92 Steel
Authors: Jing He Min , Wang Bo , Xiong Dang Sheng , Xu Yin Geng , Wang Jun Jie , Wang Peng Zhan , Liu Guang Hui , Zhang Yan
Published: February 2011

The use of P92 is becoming more and more widespread in high temperature steam pipe of super-ultracritical power station boilers, it’s key material for the manufacture of boiler’s four main pipes. The properties of P92 are closely related with its microstructure, and the microstructure of P92 has strong relationship with its’ composition and hot processing technology. Three types of P92 with different composition have been prepared. The relationship of delta ferrite between composition, smelting and heat forging process has been investigated for these three samples. The results show that the delta ferrite can be avoided by the adjustment of composition and making process, the delta ferrite will occurred in the matrix of P92 which without delta ferrite before heat treatment if the heat temperature exceed 1200°C , the delta ferrite existed in P92 ingot matrix resulted from the composition cannot be eliminated by hot working and heat treatment.
Influence of Yttrium and Heat Treatment on Microstructure and Mechanical Properties of AM60 Alloy
Authors: Tian Zheng , Cao Zhan Yi , Meng Jian
Published: February 2011

The effect of yttrium addition and heat treatment on the mechanical properties and microstructure of AM60 magnesium alloy have been investigated using X-ray phase analysis, microstructure investigation, tensile test, hardness measurement and fracture surfaces analysis. The results showed that the mechanical properties of the alloys were obviously improved with the addition of yttrium no more than 1.0%. The reinforcement of the alloys resulted from the appearance of Al2Y phase. After solid-solution treatment (T4), the Mg17Al12 phase almost dissolved in Mg matrix, but the rare earth compounds Al2Y phase was rather stable. The ultimate tensile strength σb was improved, but the yield strength σ0.2 and elongation δ were only slightly changed. After solid-solution + aging treatment (T6), the Mg17Al12 phase precipitated again and their morphology was changed. The yield strength σ0.2 was improved.
Effect of Ni on Characteristics and Structure of Aluminium Brass
Authors: Cai Wei , Hu Zao Qi , Liu Hong Fang
Published: February 2011

Studying effects of Ni content (0.6%, 0.8% and 1.0%) on structure and properties of aluminum brass (Cu-22.7Zn-3.0Al) as-cast ingot, cold-rolled and annealed sheet. The results show that: Ni can restrain the precipitation of β phase, and increase percentage of α phase during casting process. The proportion of α phase of ingot as-cast grows up with the increase of Ni content in the alloy. α phase refines gradually and shape changes to needle-like and distributes more uniform with the increase of Ni. The average grain size of α phase of ingot as-cast is 33.57μm, 31.78μm and 28.32μm respectively, and the percentage of α phase as-cast is 69.73%, 75.18% and 78.91% corresponding to 0.6%, 0.8% and 1.0% Ni respectively in the alloy. The tensile strength and hardness enhance and elongation drops with the increase of Ni content. The hardness, tensile strength and elongation is 238.7HV, 784.9MPa and 3.7% respectively for 0.2mm thickness cold-rolled sheet with 1.0% Ni in the alloy. The sheet from 1.0mm to 0.2mm thickness undergoes deformation and heat-treatment process. The hardness and tensile strength of cold-rolled strip of 0.2mm thickness are 205HV and 691.16MPa that increase 13.25% and 16.45% than cold-rolled sheet of 1.0mm thickness.
Characterization of β′ Precipitate Phase in Aged Mg-12Gd-2Y-0.5Sm-0.5Sb-0.5Zr Alloy
Authors: Li Ke Jie , Li Quan an , Zhang Xiao Hui
Published: February 2011

The Mg-12Gd-2Y-0.5Sm-0.5Sb-0.5Zr alloy was prepared under flux protection. The morphology and crystal structure of β′ precipitate phases in aged alloy has been studied using transmission electron microscopy and X-ray diffraction. The orientation relationship between β′ precipitate and matrix could existed as [ 010]BαB// [ 00]Bβ′B, (01 0) BαB// (020)Bβ′B and (0001)BαB was coherent with (001)Bβ′B; [0001]BαB// [001]Bβ′B, (1 00)BαB// (240)Bβ′B and ( 010)BαB was coherent with (0A_,8EEA0)Bβ′B. The HREM images indicated that the β' precipitates have a long-period ordered structure at the same time.
Effects of Sb on Microstructure and Mechanical Properties of Mg-5.5Al-1.2Y Alloy
Authors: Li Chang Qing , Li Quan an , Zhang Xing Yuan , Zhang Qing
Published: February 2011

The microstructure and mechanical properties of aged Mg-5.5Al-1.2Y magnesium alloy with Sb addition are investigated by optical microscope, SEM and X-ray diffraction analyzer. The results show that with proper content of Sb addition,the microstructure of Mg-5.5Al-1.2Y magnesium alloy is refined obviously and high melting point intermetallic compounds Sb3Y5 and Mg3Sb2 are formed. Meanwhile, the β-Mg17Al12 phase is more distributed. With the increase of Sb addition, the mechanical properties of the alloy at room and elevated temperature increase at first, and then decrease. When the content of Sb is up to 0.5%, the values of tensile strength and elongation at room temperature, 150ºC and 175ºC are up to their maxima synchronously, 241MPa /16.84%, 198MPa/20.27.86% and 169MPa/21.21% respectively.
Preparation and Characterisation of Al/Pb Layered Composite Materials
Authors: Zhou Sheng Gang , Zhu Pei Xian , Sun Yong , Sun Li Da
Published: February 2011

Taking Sn as the third element in the Al/Pb immiscible system, the Al-Sn-Pb layered composite materials at different temperatures were prepared by solid-liquid coating method. Microstructure of the layered composite materials was studied by scanning electron microscope (SEM) and Energy Dispersive Spectrometer (EDS), and then the flexural strength and interface adhesion of the layered composite materials were measured. The results showed that, introducing of Sn reduced the enthalpy heat of mixing of Al/Pb system to be negative, and inter-diffusion of elements in the interface region occurred, and a metallurgical bonding interface between Pb and Al formed. The optimum diffusion-sintering temperature-time for the best flexural strength were determined by 250οС , 0.5h, respectively. Under the controlled conditions, the mechanism was discussed.
An Analytical Method for 3-Phase Model of Electro-Magneto-Elastic Fiber Composites with Periodically Distributed Reinforced Phases
Authors: Xu Yao Ling , Hou Hong Li
Published: February 2011

The response of electro-magneto-elastic long fiber composites containing periodically distributed reinforced phases under antiplane shear load coupled with inplane electromagnetic load is dealt with, there are three different electro-magneto-elastic materials in the unit cell (3-phase model), a rigorous analytical method is developed by using the generalized eigenstrain concept integrated with the doubly quasiperiodic Riemann boundary value problem theory. As an important application of the presented solution, the effective electro-magneto-elastic moduli are predicted and compared with the results from the generalized self-consistent method.
Precipation and Dissolution Behaviours of Secondary Phase in J55 Steel During Continuous Casting, Conveying and Heating
Authors: Wang Ming Lin , Zhang Hui , Zhu Zheng Hai
Published: February 2011

With development of theory on microalloy in steel, now there are trends of adding microalloy in many kinds of steels, making the production and application of microalloy-steel enlarge. The second phase in microalloy-steel is significant for quality of casting. During the periods of continuous casting, conveying and heating, different process may affect precipitation and dissolution behaviors of casting according to different heating profile, further affect state of precipitation and distribution of secondary phase. In this paper, secondary phase in micro-alloy steel J55 were studied. Results show that some secondary phase particulars in micro-alloy steel J55 steel distribute along the austenitic grain boundaries when the temperature of slab is below 805°C in roller conveying; The distribution of secondary phase particulars in different thermal history slab are comparatively similar after heating; Al, Ti, C and N elements which dissolute in J55 steel has the feature of austenitic grain boundary segregation.
Study on the Natural Fiber/pp Wrap Spun Yarns Reinforced Thermoplastic Composites
Authors: Zhang Lu , Huang Gu , Liu Zhen Zhong
Published: February 2011

Composites made from yarns perform better than composites made from random nonwoven mats. However, the twist structure of conventional ring spun yarns prevents the full utilization of fiber mechanical properties in the final composites. We produced flax/pp wrap yarns in which all flax fibers were twistless. Composites made from the wrap yarn gave a significant improvement of flexural properties. Most natural fibers, such as decorticated hemp, cannot be efficiently made into yarns because of their lack of cohesion. Adding pp fibers to decorticated hemp improved textile processing performance. The pp fibers served as a carrier for the natural fibers during processing and became the polymer matrix in the final composites.
Effect Of PP-G-MAH on the Compatibility of Lignin/LDPE Composites
Authors: Lv Xin Ying , Zhang Yan Hua , Di Ming Wei
Published: February 2011

Lignin have been blended with low density polyethylene (LDPE). Maleic anhydride grafted polypropylene (PP-g-MAH) has been added as compatibilizing agent. The weight ratio of LDPE, ligin and PP-a-MAH were 75:25:5, 75:25:7.5 and 75:25:10, respectively. The mechanical properties of the blends were investigated according to Chinese standard GB/1447-2005 and compared with those of lignin/LDPE composites without compatibilizing agent. Scanning electron microscopy (SEM) was used to investigate the dispersion of the lignin and LDPE and the compatibilizing mechanism was analyzed. The results reveal that addition of compatibilizing agent increased the interfacial bonding strength of the composites, improved the mechanical properties and obtained the better dispersion of the lignin and LDPE.
Separable K-Canonical Formulation of Rectangular Element and Symplectic Integration Method for Analysis of Laminated Plates
Authors: Qing Guang Hui , Wang Liang , Shi Li Zhong
Published: February 2011

In the state space framework, a separable K-canonical formulation of rectangular element and explicit symplectic schemes for the static responses analysis of three-dimensional (3D) laminated plates are proposed in this paper. Firstly, the modified Hellinger-Reissner (H-R) variational principle for linear elastic solid is simply mentioned. Secondly, the separable J-canonical system with Hamiltonian H and the separable K-canonical formulation of rectangular element are constructed. Thirdly, on the basis of the symplectic difference schemes, the explicit symplectic schemes are employed to solve the separable K-canonical governing equation for a single plate. Then, to obtain the high accurate numerical results, a multi-scale iterative technique is also presented. Finally, based on the interlaminar compatibility condition (displacements and stresses), the excellent performance of the method presented in this paper is demonstrated by several numerical experiments of the static responses of laminated plates.
Effects of Wood Powder on Mechanical Properties of PP/Wood Powder Composites
Authors: Yu Cheng Bing , Rui Yin Yu , Chen Sai Sai , Lv Xia , Lv Xi Lin
Published: February 2011

Effects of wood powder (WP) on mechanical properties of PP/WP composites were studied, and interfacial compatibility between polypropylene (PP) and WP was investigated with SEM. All PP/WP composites were compounded in a parallel twin-screw extruder. Mechanical properties of composites were characterized by tensile, hardness, and impact testing. The result showed that interfacial compatibility in PP/WP composite was ameliorated efficiently by PP-g-(MAH-St) compatilizer, mechanical properties of PP/WP composites were improved by pre-treating WP with alkali and coupling agent. They were also influenced by WP size and WP amount, which were the best at the size of 60-mesh and the amount of 40 wt%.
Sliding Wear Behaviour of Cu-10Fe-3Ag In Situ Composite
Authors: Li Yong , Yi Dan Qing , Liu Rui Qing , Sun Shun Ping
Published: February 2011

A deformation-processed Cu-10Fe-3Ag in situ composite was made by consumable arc melting and casting followed by extensive deformation. A superior combination of mechanical strength and electrical/thermal conductivity was achieved with the composite since Fe filaments existed in the copper matrix. The effects of sliding speed and electrical current on sliding wear behavior and microstructure of the composite were investigated on wear tester. Worn surfaces of the Cu-10Fe-3Ag in situ composite were analyzed by scanning electron microscopy (SEM). Within the studied range of electrical current and sliding speed, the wear rate increased with the increasing electrical current and the sliding speed. Compared with Cu-10Fe in situ composite under the same conditions, the Cu-10Fe-3Ag in situ composite had much better wear resistance. Adhesive wear, abrasive wear and arc erosion were the dominant mechanisms during the electrical sliding processes.
Microstructure and Properties of La-Doped Ag-SnO2/Cu Contact Material
Authors: Fu Chong , Wang Jun Bo , Yang Min Ge , He Xin Hai , Su Xiao Lei , Xu Jie
Published: February 2011

The undoped and La-doped nanostructured Ag-SnO2 coatings on pure copper substrate were prepared by supersonic plasma spraying. The phase compositions and microstructures of coatings were characterized and mechanical properties including micro-hardness and bonding strength of coatings were measured. Meanwhile, conductivity test was performed on the both Ag-SnO2/Cu contact materials. Compared with undoped Ag-SnO2 coating, La-doped Ag-SnO2 coating exhibits the more dense structure with fewer pores, and show slightly higher micro-hardness and bonding strength. Doping La can effectively enhance the electrical conductivity of Ag-SnO2/Cu contact materials.
Effects of Stitching Reinforcement on Mechanics Behaviour of Composite Π Joint under Tensile Loading
Authors: Zhang Jian Yu , Fu Yue , Zhao Li Bin
Published: February 2011

Stitched woven composite π joints and paralleled samples without stitching were investigated by numerical analysis under tensile loading. The effects of stitching on the mechanics behavior of composite π joints are presented. Stitching technique can reduce initial failure load of composite π joint, but remarkably improve the rupture load. The failure process of composite π joint, including the damage onset, propagation path and final failure pattern, is also limited in the stitched area. The failure mechanisms are expatiated by the numerical data and failure picture to obtain more knowledge about the mechanics behavior of composite π joints.
Research on New Technology to Control Highway Semi-Rigid Base Asphalt Pavement Cracks
Authors: Deng Hong Liang , Fu Xiao Yin , Gao Wen Xue , Ni Ting Ting , Chen Kai Jiang
Published: February 2011

The methods of controlling Highway semi-rigid base asphalt pavement cracks and other diseases are always hot fields of road engineering and academic circles. The existing methods are on some degree efficient on delaying the formation and extension of cracks, but the effect is limited with different methods and various mechanisms of preventing cracks. Base on force analysis of pavement, this article presents a new technology of crack controlling which uses intelligent composite materials interlayer. By adding a stress absorbing layer between the asphalt surface layers or the semi-rigid base layers with low modulus, good toughness, self-adaptability and self-control ability, the intelligent composite materials interlayer has a good effect on controlling cracks which has been proved by the theoretical calculations and experimental analysis. As a result, the intelligent composite materials interlayer could efficiently prevent and delay the formation and extension of cracks, the safety and comfort of highway could be improved significantly while the cost of construction and maintenance decreasing. And the service level and social image of the road could also be improved effectively. This research has important academic and application value.
Study on the Orientation Angle of the Yarns in 3D Integrated Cellular Woven Structure
Authors: Tian Wei , Li Yan Qing , Ye Fei , Zhu Cheng Yan
Published: February 2011

Three-dimensional (3D) integrated cellular woven structures are formed by binding layers of typical 3D woven structures together in the thickness direction with binding threads. On the basis of the geometric model established during previous work, the orientation angle of binders in the basic structure was analyzed firstly, and then the orientation angle of binders and warps in the 3D integrated cellular woven structure were also studied. And at last following conclusions could be gotten: Firstly, the orientation angles Qb of the binders will be larger as the regularizing filling density pw increasing when other parameters (λw ，Nft ，bb ) are all the same. It turns out the adjusting function of the regularizing filling density is a little sensitive to the orientation angle of binders in the basic structure. Secondly, the orientation angle Qcj of the warps will be larger as the regularizing filling density pw increasing when other parameters (λw ，nd ，bb ) are all the same. It turns out the adjusting function of the regularizing filling density is a little sensitive to the orientation angle of warps for 3D integrated cellular woven structures.
The Different Probabilistic Method for the Conservatism Analysis of Composite Structure Damage Tolerance Design
Authors: Zou Tian Chun , Feng Zhen Yu , Mou Hao Lei , Mao Ke Yi
Published: February 2011

The result shows: If probabilistic methods were used to conduct compliance analysis for composite structure damage tolerance. When the impact energy is low, calculated result should conservatively use probabilistic methods of Weibull distribution fitting; when the impact energy is high, calculated result should conservatively use probabilistic methods of logarithmic linear fitting.
Synthesis of B4C/Al-B4C/TiB2 Composite with a Two-Layer Structure
Authors: Yue Xin Yan , Ru Hong Qiang , Zhang Cui Ping , Wang Wei
Published: February 2011

A two-layer structure composite based on B4C/Al-B4C/TiB2was prepared using hot pressing and infiltration aluminum in vacuum. The results showed that the B4C porous layer in the two-layer preform looked like a three-dimensional network of interconnected capillaries which could promote the infiltration of liquid aluminum. In the B4C/TiB2layer the TiB2dispersed homogenously in B4C matrix. After infiltrating process the two-layer B4C/Al-B4C/TiB2composite with good interfacial bonding was obtained.
Fabrication Porous Si3N4 -Glass Composite by Combustion Synthesis
Authors: Li Wen Kui , Luo Shan Shan , Zhuang Han Rui
Published: February 2011

This paper presents the results of synthesizing porous Si3N4-glass composite with Y2O3 as additives by combustion synthesis. The effect of glass content on the final morphology was investigated in detail. The results reveal that the final morphology of products is depended on the glass content. With the increasing glass content, the porosity of the composite is decreasing and the highest strength is obtained when the glass content is 2wt%.
Effect of Sintering Temperature on Al2O3/TiAl Composite from Ti-Al-TiO2-Eu2O3 System
Authors: Wang Fen , Wang Xiao Feng , Zhu Jian Feng , Xiang Liu Yi
Published: February 2011

In this work, the composites were fabricated by in-situ synthesis reaction and hot-pressing using Ti, Al, TiO2 and Eu2O3 as starting materials. Effects of the sintering temperature on the microstructures and properties of the Al2O3/TiAl composites were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and universal properties tests. The result shows that the sintering temperature had effect on improving the mechanical properties of TiAl composites. The phase of the composites composed of γ-TiAl/α2-Ti3Al matrix and reinforcing phases of Al2O3 and EuAlO3. The grain size of composite was smaller than 0.5 µm at 1200 °C. And the mechanical properties reached to the maximum value (477.96 MPa and 9.73 MPa•m1/2). The properties decreased with grain growth at 1300 °C.
Properties Research of Cotton Fiber Reinforced Gypsum Based Composites
Authors: Zhang Wei Hao , Li Guo Zhong , Liu Min Rong
Published: February 2011

Cotton fibers and gypsum were taken as the raw materials to manufacture cotton fiber reinforced gypsum based composites. Optimum length and dosage of cotton fiber and mixing method were confirmed in the experiments. The effect of cotton fiber on mechanical properties and waterproof properties of composites were studied. The reinforcement mechanism of cotton fibers on composites was discussed.