bluuebunny/crossref_metadata_2025_split huggingface dataset:
An experiment of lubricating oil gas concentration in the standardized driving cycles
Authors: Lin J , Liu Y Q 
Published: August 2020

Abstract
There always is cavitation in the positive displacement pump, and the bubbles in the lubricating oil have a great influence on the lubricating performance. This paper aims to measure the lubricating oil gas concentration of a passenger car gasoline engine in the standardized driving cycles. We use a passenger car engine lubricating system in the lubricating experiment, simulating the lubricating oil pump working state in the standardized driving cycles. The lubricating oil density and flow rate are measured to calculate the gas concentration in the lubricating oil, according to the engine work state in the standardized driving cycles, including NEDC Urban, NEDC Ultra Urban, WLTC High Speed. The test results show that under the steady-state conditions, the gas volume ratio decreases linearly with the increase of the outlet pressure, the air mass ratio increases with the increase of the pump speed. In the driving cycles, the air mass ratio also increases with the increase of outlet pressure, and it has a high positive correlation with lubricating oil flow and pump speed. With the increase of oil temperature from 25 to 100°C, the air volume ratio decreases by 72.6%, and the air mass ratio decreases by 84.3%. In the engine accelerating state, the rate of lubricating oil flow gain lags behind the pump speed, which makes the lubricating oil gas mass ratio in the accelerating state is significantly higher than that in the decelerating state.
A Nozzle Structure of Wire Drawing Prevention for 3D Printing Fused Deposition Manufacturing
Authors: Jieqiong Fu , Leping Bu , wenping Zeng , yong Zhang 
Published: August 2020

Abstract
The working principle of 3D printing fused deposition Manufacturing is introduced. The reasons for the problems of nozzle material flow and product wire drawing in the process of product printing are pointed out. The structure of traditional nozzle is analyzed, and a new structure of nozzle is proposed. The main feature of the new nozzle structure is that it can generate negative pressure in the closed space when the wire is withdrawn, thus it can effectively prevent the nozzle flow and product drawing. At the same time, by optimizing the heat dissipation system of the new nozzle structure, the stability of the nozzle printing process can be improved. The practical application shows that this new nozzle structure is effective and worth popularizing.
Hydraulic Control Research of Working Device of Grab Arm Cleaning Machine for Heavy Load and Large Depth
Authors: Yuanlong Chen , Ziquan Wang , Rongna Chen 
Published: August 2020

Abstract
In this paper, a kind of heavy-duty and deep cleaning machine working device is studied. The closed-loop vector method is used to establish the kinematics model of the hydraulic cylinder rod mechanism, and the Lagrange dynamics is used to establish the dynamic model of working device. MATLAB, AMESim and ADAMS are used to provide excitation signal for the servo valve, build the hydraulic simulation model, and carry out kinematics and dynamics simulation. Using different signal excitation, the displacement tracking of the working device and the change of hydraulic pressure are observed. The results show that the closed-loop vector method and Lagrange dynamics are used to establish the kinematics and dynamics model of the working device, which facilitates the study of the working device of the cleaning machine; the simulation interface is stable, and the co-simulation of control arithmetic is achieved, hydraulic system and structural dynamics; the hydraulic pressure is obtained through the co-simulation analysis. The effect of cylinder displacement tracking and the change of hydraulic pressure provided the basis for working device design and optimization.
A design method of acoustic metamaterials with buckling vibrators
Authors: Qin Shenghui , Wang Xiaoming , Mei Yulin 
Published: August 2020

Abstract
This paper proposes a periodic acoustic metamaterial with buckling vibrators, and investigates the design method for the band-gap characteristics of the acoustic metamaterial. The unit cell of the acoustic metamaterial is constructed by a continuous bar, curved beams embedded into the bar and the mass supported by the curved beams. The band structure of infinite period and the transmission characteristics of finite period are researched to analyze the effect of the structural and material parameters of the curved beam on the band-gap characteristics of the unit cell. And the effect of pre-strains applied to the curved beam on the band-gap characteristics is also discussed. The research illustrates that the acoustic metamaterial with buckling vibrators has a low frequency band-gap of 100-125Hz; in the frequency range of 0-200Hz, the central frequency of the band-gap increases with the increase of the beam width; the curvature radius of the beam has little influence on the central frequency of the band-gap, and a big bandwidth of the first band-gap can be obtained when the curvature radius is 20 mm; by applying pre-strain to the curved beam in a certain extent, the central frequency of the band-gap can be effectively reduced, and the attenuation more than 100 dB can be guaranteed.
A Design Method for Labyrinth Sound Absorption Structure with Micro-perforated Plates
Authors: Yu Dequn , Wang Xiaoming , Mei Yulin 
Published: August 2020

Abstract
A kind of labyrinth sound absorption structure is constructed by embedding multi-layer micro-perforated plates into a pipeline, and a design method is proposed to optimize its parameters to ensure a good sound absorption performance. First, the effects of parameters of the labyrinth structure on the sound absorption performance are investigated. Second, a parameter optimization method is constructed based on the acoustic impedance transfer analysis and particle swarm optimization algorithm. Then, a simulation experiment is implemented by means of COMSOL to verify the optimization results. Finally, the labyrinth structures with straight pipeline, spiral pipeline and parallel pipeline are designed and their sound absorption performances are evaluated and compared. The research shows that, the effects of the perforation diameter, the plate thickness, and the perforation rate on the sound absorption performance are non-independent while the effect of the depth of cavity is independent; the weighting coefficient in the parameter optimization method could be adjusted to ensure a big absorption bandwidth in a low frequency range; in the frequency range of 30-4000 Hz, the labyrinth structure with straight pipeline and the labyrinth structure with spiral pipeline have the same sound absorption performance; for the labyrinth structure with parallel pipeline, the inner corner radius of pipeline has a great influence on the sound absorption performance, and the radius should be greater than 20mm.
Experimental Research and Mechanical Analysis of Levelling Parametric Characterization of 3D Printer
Authors: Lianghua Zeng 
Published: August 2020

Abstract
Based on the Delta 3D printer this paper carries out levelling experimental research and explores the changes of position parameter of the moving parts when the hot bed is in the horizontal and inclined states. It also conducts a comparative analysis to find a method for parametrically characterizing the levelling states of the 3D printer, and grasps the attitude characteristics of the nozzle in different levelling states. At the same time, the paper also carries out a mechanical analysis to explore the effect of the blowing direction of the fan and the inclination of the hot bed on print quality under different levelling states.
Research about a Kind of Gantry Type Single-side Drive Straight Line Motion Mechanism
Authors: Jieqiong Fu , Leping Bu , Hailin Li , Yong Zhang 
Published: August 2020

Abstract
The article mainly has conducted comparison to three kinds of frequently-used long-span gantry type mechanism that do straight line motion, which thereby has obtained that the gantry type single-side drive mechanism hads possessed relatively prominent advantage in the smoothness, assembly debugging, reliability and maintenance aspects of the motion and it has conducted reason analysis and structural improvement to problems existed in occasions of its application in large scale equipment, long span or heavy load with impact, which therefore haves guaranteed the need for high precision and high stability in practical application.
Research on Pure Mechanical Lifting Pedal Applied to Rail Transit Vehicles
Authors: Zhang Yingyong , Hou Zhaozhan , Lin Xiangli , Xia Changkai , Yang Dongjun , Song Jianwei 
Published: August 2020

Abstract
With the continuous development of rail transit industry, the comfort level of drivers and the flexibility requirements of customers for the different vehicle of console are continuously improved. At present, the lifting pedal has been widely used in the industry, which are hydraulic and electric type. Pure mechanical lifting pedal has not been applied in the rail transit vehicles. Considering the service life and reliability of the products, many customers, especially foreign customers, require the pure mechanical structure to meet the requirements of different vehicle models and meet the requirements of different drivers for the console. This paper proposes a kind of pure mechanical lifting pedal applied to rail transit vehicles, which can meet the adaptability of the console to different vehicle bodies and drivers, and greatly improve the universality and reliability of the application.
Analysis of CMM Dynamic Measurement Error Based on Decision Regression Tree
Authors: Wu Xiaoping , Zhang Mei , Li Guihua , Zhao Haifeng , Wu Haiting 
Published: August 2020

Abstract
The best way to improve the accuracy of coordinate measuring machine (CMM) is to establish a correlation dynamic error correction model. However, due to the complex source of dynamic measurement error, the traditional method cannot work well. In this paper, decision regression tree is used to analyze the complex relationship between dynamic measurement error and its influencing factors, and the measurement error is predicted. The results show that the algorithm is simple, fast and superior to the least square estimation.
Research on Multi-Order Anti-Aliasing Filter in Bearing Profile Detection
Authors: Gaoqing He , Jiang Han , Leilei Liang , Jian Xiao 
Published: August 2020

Abstract
In the process of bearing profile detection, an analog displacement sensor is used, but there is noise interference in the process of data acquisition. In order to suppress noise interference, the paper designs three-order and fifth-order anti-aliasing filters according to the actual interference signal source. The resistance value and capacitance value are calculated according to the transfer function. The real object is made by the porous simulation board. The comparison between the input and output signals shows that the fifth-order anti-aliasing filter is better than the third-order anti-aliasing filter. Experiments show that the higher order anti-aliasing filter has a certain suppression effect on the noise signal, but the effect is not obvious. The signal distortion would happen and the system would become more and more complicated. For this reason, the fifth-order anti-aliasing filter is finally selected, and the actual sampling is completed, and the effect reaches the requirements of the detection system.
Application of 3D printing technology in equipment structure teaching
Authors: Xiaotao Bai , Jie Li 
Published: August 2020

Abstract
Aiming at the characteristics and current situation of equipment construction teaching, with the help of 3D printing technology, the production, assembly and demonstration of typical equipment model of equipment can be realized, and the teaching effect of equipment construction course can be significantly improved through specific application. At the same time, it puts forward reasonable suggestions for the popularization and application of 3D printing technology in teaching, and provides a reference for the reform of equipment structure teaching.
Experimental Research on The Distribution Law and Formation Reasons of As-cast Magnesium Alloy Laser Welding Porosity
Authors: Shen Yan-Jin , Zhou Jing , Liu Qian , Wu Fangrong 
Published: August 2020

Abstract
Characteristics and distribution of the weld porosity are observed by using OM and SEM after as-cast magnesium alloy AZ91D is welded by CO2 laser. And then the formation model of two types of porosity is established by use of organization composition and distribution of metal base. Besides, the mechanism of pores in welding is explained on three aspects including microscopic porosity, macroscopic porosity and escape of bubbles. Based on these models and mechanisms, the shape characteristics and distribution of a welding porosity in a welding seam is explained and the formula of bubbles escape is also given. In addition, the measures to prevent welding porosity are discussed preliminarily. And based on the preliminary research on this topic, when (0.2%Ca+0.4%Y) is added to AZ910D magnesium alloy and high strain rolling is used, the laser weld porosity ratio of magnesium alloy can be effectively reduced.
Research on the Combustion Performance of Mixed Charge of the Super-porous Coated Propellant
Authors: Xiang Cao , Lina Zhang , Ping Du , Shuai Jiang , Fengqiang Nan 
Published: August 2020

Abstract
In order to study the constant volume combustion performance of the mixed charge of super-porous propellant and super-porous coated propellant, 37-hole nitroguanidine propellant and 37-hole nitroguanidine coated propellant containing flame retardant TiO2 were prepared. At high temperature(50°C), normal temperature(20°C), low temperature(-40°C), a constant volume combustion experiment was performed on a mixed charge with a mass ratio of 1: 1 for the 37-hole propellant and the 37-hole coated propellant. The research results show that the constant volume combustion performance of the mixed charge is different from a single coated propellant and a single base propellant. The p-t, dp/dt-t and L-B curves of the mixed charge were between the coated propellant and the base propellant, but mixed charge has the greatest progressive combustion. And the temperature dependence of the progressive combustion of mixed charge is small, which has a certain low temperature effect.
Crack Growth Analysis of Rail Transit Steel Bridge Components Based on Damage Tolerance
Authors: Jia Yuanping , Cai Guoqiang , Sun Ruizhi , Li Qiang , Yang Chen 
Published: August 2020

Abstract
In recent years, the accidents caused by the instability and failure of the steel structure of the bridge occur frequently. Therefore, the research on high-performance steel members is one of the key directions of the development of Engineering Technology in the 21st century. In this paper, the damage tolerance evaluation method based on the finite element calculation of crack growth is used to analyze the fatigue of the load-bearing carbon fiber suspender with cracks in the operation stage, to correctly evaluate the remaining life and the remaining safety of the component, and to effectively handle Grasp the status and disease development of the bridge, so we can take timely and targeted measures to ensure the safety of the bridge.
Research on the Optimization of Process Parameters of the Current-Assisted Flow Spinning for 30CrMnSiA Cup-Shaped Part with Different Thickness
Authors: Can Chen , Lei Wang , Xiao Xu , Qinxiang Xia 
Published: August 2020

Abstract
A multi-pass current-assisted flow spinning experiment was carried out for the cup-shaped part with different thicknesses. The thickness deviation At, straightness u, and roundness e of the spinning parts were selected as the evaluation indexes of forming quality, and the effects of process parameters such as current intensity, preheating time, feed ratio and thinning rate on the forming quality were studied. Based on the genetic algorithm and BP neural network (GA-BP) model, the quality prediction model for the current-assisted flow spinning process was established, and the forming process was optimized by the genetic algorithm (GA). The verification test results are close to the predicted values of the model, in which the maximum error between the predicted value and the test result is about 6%. The results show that the proposed method is useful for the optimization of the current-assisted forming flow spinning process.
High-temperature tensile behavior of 3D SiC/SiC composites
Authors: Zhang Yu , Jiang Yun , Ren Duqiang , Zhang Qiang , Wang Xiaodong 
Published: August 2020

Abstract
The high-temperature tensile properties and stress-strain behavior of a 3D SiC/SiC composites prepared by the PIP method were investigated. Based on the FESEM analysis of the fracture morphology, the tensile failure mechanism of the composite at elevated temperature was discussed. The results show that the tensile strength of SiC/SiC composites showed a significant decline for specimens from a room temperature value of 482.5 MPa, to 167 MPa and 138 MPa at 1100 °C and 1300 °C, respectively. The toughening mechanism of composites at 1100 °C, including interface debonding, long pull-out fibers, and fracture mirror characteristics, is consistent with the pseudo-plastic fracture behavior implicated in the stress-strain curve. As a result of more significant oxidation, the fracture morphology of the specimen tested at 1300 °C was characterized by the signs including fiber-to-fiber bonding, larger size glassy phase, and shorter fiber pull-out length.
Study on the influence of post-treatment conditions on the internal stress of polystyrene products
Authors: Jin-wei Chen , Ling Yang , Li-xuan Wu , Da-hua Chen , Qun-shan Mai , Qiu-xian Weng , Xiang Liang , Shi-xin Su , Qi-qi Zhang 
Published: August 2020

Abstract
The polymer products in daily use generally have internal stress, and the uneven or excessive distribution of internal stress will cause warpage or stress cracking, which will affect the normal use of products. Using the heat treatment method of metal annealing to reduce its internal stress for reference, the polymer products were placed in the drying oven and water bath pot for post-treatment, and the influence of different post-treatment process parameters on the internal stress of polystyrene products represented by the mobile phone lens products was studied by using the self-developed molecular material transparent products internal stress detection device. The results showed that increasing the post-treatment temperature below the hot deformation temperature can effectively reduce the internal stress and improve the internal stress distribution of polystyrene products at the same post-treatment time under different post-treatment temperatures and slow cooling conditions, and there was an optimal post-treatment temperature of 60 Centigrade;the polystyrene products after post-treatment had the secondary internal stress under the rapid cooling conditions, so that the internal stress distribution of products was worse than that of polystyrene products without post-treatment. The experimental results can lay a theoretical and practical foundation for seeking effective measures to reduce the internal stress of polymer products in the future.
A Comparative Study of Selective Laser Melting Processed Inconel 625 Superalloy: Fatigue Performances under Constant Amplitude Loading and Single Tensile Overload
Authors: Ren D Q , Jiang Y , Zhang Y , Hu X A 
Published: August 2020

Abstract
The Inconel 625 used in this study was fabricated by the selective laser melting technology. The fatigue properties of this alloy were investigated at room temperature. The compact-tension specimens were used to study the fatigue crack growth behaviors under stress ratio R = 0.1, and overload ratio ROL = 1.4. Three typical behaviors of overload fatigue crack growth (increase, drop and increase) were studied.
Application of polyaspartic acid derivative in circulating cooling water system with high concentration multiple
Authors: Gao Y H , Li H H , Zheng Y X , Zhang L H , Liu Z F 
Published: August 2020

Abstract
The polyaspartic acid derivative compound was applicated in circulating cooling water system with high concentration multiple with the water quality of circulating cooling water system was characterized by higher hardness, higher alkalinity and higher corrosive ion content in order to solve the problem of scale and corrosion of the circulating cooling water system. The formulation of the polyaspartic acid derivative compound was determined to be PASP-AESA-ASP, ZnSO4, HPAA and BTA with the mass ratio of 15:4:6:0.1. The polyaspartic acid derivative compound had a good protective effect on A3 carbon steel in high-concentration-salt water and good biodegradability.
Experimental Investigation on Face Grinding of 2024AI/SiCp with Electroplated Diamond Wheel
Authors: Shaolei Wang , Shuzheng Shi , Jiuqiang Wang , Xin Li , Zhanying Wang , Chunhua Zhu 
Published: August 2020

Abstract
SiCw / 2024Al composite has excellent physical and chemical properties, such as high specific strength, good wear resistance, low coefficient of thermal expansion, etc. It has been widely used in the development of modern science and technology. An experimental research on face grinding of SiC particle-reinforced aluminium matrix composite 2024Al/SiCp with electroplated diamond grinding wheel was carried out. The effects of different grinding parameters on the surface morphology, grinding force and grinding quality of workpiece are analyzed. The results show that high quality ground surface can be achieved by using this technology; the residual stress on machined surface is compressive stress; grinding parameters have little effects on tangential and normal grinding forces, but have stronger effect on axial grinding force than that in other two directions, and the axial grinding force increased notablely as the increasing of grinding depth.
Expermental Research on Light-curing Rapid Prototyping Silicon Oxide Ceramics
Authors: Yan Liang , Yuan WenJing , Yan Biao 
Published: August 2020

Abstract
3D printing technology is an emerging technology that is rapidly developing in the manufacturing field. It can easily and automatically manufacture complex three-dimensional shapes that are difficult to be produced by various processing methods. Printable ceramic materials are prepared by mixing photosensitive resin and different ceramic powders. By studying the effects of dispersant, slurry, PH value, silica particle size and solid phase content on slurry viscosity and fluidity, low viscosity Ceramic slurry with high solid phase content and good fluidity. The effects of different solid phase contents on the bending strength, firing shrinkage, porosity and density of ceramics were tested. The results show that the bending strength of sintered SiO2 ceramics reaches 15.78Mpa at a solid content of 70vol %. The density was 76.21%, porosity was 40.04%, sintering shrinkage was 0.89%.
Effect of inclusion defect on fatigue failure of FGH96 superalloy at 600°C
Authors: Miao Guolei , Sun Tong , Wang Xiaodong 
Published: August 2020

Abstract
High cycle fatigue experiments were conducted at 600°C to study the effect of manufacture defect on crack initiation behaviour of FGH96. The experiments were performed at different stress levels to considering the coupling effect of loading and defect. The stress ratio was selected at 0.05. The results revealed that the fatigue life behaviour are much different in different loading levels. In order to examine the crack initiation mechanism, Scanning electron microscopy (SEM) method was used to analyze the failure surfaces. Different failure modes including surface cracking, sub surface cracking as well as internal crack initiation were found. The tested fatigue lives were found to have a strong relation with the mode of the crack initiation.