bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanical properties and injection molding processability of glass fiber modified polylactic acid composites
Authors: Liu Weiliang , Qiu Tianyang , Wang Liang , Jiang Wei
Published: December 2022

In order to promote the development and application of environment-friendly plastics, a glass fiber-modified starch/polylactic acid composite was prepared by the melt extrusion method. The influence of glass fiber content on the mechanical and thermal properties of the composite was studied, and multi-objective optimization of the injection molding process was carried out with consideration of the influence of material properties. The results show that with the increase of glass fiber content from 0 to 5%, the tensile strength of the composite decreases first and then increases to an average of 60Mpa, which is about 30% higher than that of pure polylactic acid. The elastic modulus and thermal stability increase, while the elongation at break and flow rate decrease with the increase of glass fiber content. In addition, the optimized injection parameters are obtained, which can effectively reduce the warping deformation, volume shrinkage, and residual stress of injection parts. Glass fiber modified starch/polylactic acid composites show great potential in engineering application, and may provide a reference for the development and application of high-performance and green degradable materials.
Characterization of the local mechanical properties of 5083-5383 MIG welded joints
Authors: Du Zhuotong , Xu Kuilong , Wang Lei , Zhang Xianfeng , Zhang Xinyao
Published: December 2022

act. Due to the heat input effect, the weld seam and heat-affected zone (HAZ) are strength weakened phases in 5xxx aluminum welded joints. Therefore, the local mechanical properties of the 5xxx aluminum welded joint are worth studying for structural design. In this paper, the local mechanical properties of 5083-5383 MIG joints were studied. Through instrumented indentation and tensile tests with digital image correlation (DIC), the yield strength of the same area of the weld center, heat-affected zone, and the base metal (BM) was respectively characterized. The two methods show good consistency in the characterization of the yield strength in each region. The tensile strength of the weld zone and BM characterized by two methods also represent good consistency. The HV0.1 and HV10 Vickers hardness distribution of welded joints was studied, and the differences in the characterization of local mechanical properties of 5083-5383MIG welded joints by instrumented indentation test, tensile test with DIC and Vickers hardness are analyzed. The instrumented indentation test can be used for approximate non-destructive quantitative characterization of the local mechanical properties of 5083-5383 MIG welded joints.
Analysis of coarse stripes of alloyed hot-dip galvanized steel sheets
Authors: Xiong Taotao , Ren Jianping , Luo Chengjian , Zuo Rong
Published: December 2022

Zinc iron alloy hot-dip galvanized steel sheet is widely used in the automobile and household appliance industry because of its good weldability, coating property, and corrosion resistance. In the production of alloyed hot-dip galvanized steel sheets, stripe defects are often found on the surface of the strip, which affects the diffusion reaction of iron and zinc and causes the defects to be amplified. Coarse stripes are one of the main ones. In this paper, the coarse stripe defect on the surface of an alloyed hot-dip galvanized steel plate was studied, by means of the Scanning Electron Microscope and Energy Spectrum, combined with the verification of galvanizing production. The results showed that the morphology of the coarse stripes defect area on the surface of the alloyed hot-dip galvanized sheet exhibited concave-convex features, and the average iron content was 1.41% lower, compared with the defect-free area, Indicating that the streak defect region was insufficiently alloyed. It is presumed that there is oxide in the region of the streak defect. By adopting the cleaning zone and adjusting the atmosphere in the furnace, the incidence of defects was reduced by 76%, and the quality of the slab was significantly improved.
A local-resonance elastic metamaterial for the transport of wheel-rail vertical vibrations
Authors: Xu Gang-Gang , Li Ren-Sheng , Gao Xing-Lin , Wen Xiao-Dong , Liu Zi-Jiang , Sun Xiao-Wei
Published: December 2022

The subwavelength artificial elastic metamaterials can be used for efficient transmission of vibration energies in a tunable frequency range. A local-resonance equal-thickness elastic metamaterial plate is designed in this work. The triangular resonators in the rhombic unit cell are used to exploit the valley degeneracy of the out-of-plane locally resonant modes under hexagonal symmetry conditions. The resonators consist of high-density cores wrapped by soft elastic material, and the differences in the intrinsic frequencies produce a topological band gap caused by the double resonant effect. The reversal of the energy bands proves that the band gap has a non-trivial topology effect, i.e., there exists edge states with robustness and high transmission efficiency. This structure can be utilized in railway transportation as an advanced elastic wave medium material to improve the efficiency of sensing and harvesting the energy of vertical vibrations between vehicles and rails.
Influence of Sintering Temperature on Electrical Properties of Sb2Te3
Authors: Bai Zhiling , Qin Bingke
Published: December 2022

Sb2Te3-based materials are thermoelectric materials with the best performance in low-temperature regions. The preparation of antimony telluride by solid-state reaction method can shorten the production cycle and improve its electrical properties. The phase and electrical properties of the samples are characterized by XRD, SEM, Seebeck coefficient, and conductivity tester. The results show that when the holding time is 60 minutes and the sintering temperatures are 673 K, 723K, 773K, and 823 K, the resistivities of the synthesized samples are 1.68 mΩ·cm, 0.86 mΩ·cm, 0.67 mΩ·cm and 0.51mΩ·cm and the Seebeck coefficients of the synthesized samples are 99.580 μV/K, 93.633 μV/K, 96.018 μV/K and 70.152 μV/K, the maximum power factors of the samples is 1376.03 μWm−1·K−2 for sample synthesized at 773 K.
Study on firing process of silicon zinc magnesium crystal glaze
Authors: Gao Quanjin , Joenurairatana Eakachat , Simatrang Sone
Published: December 2022

It is complicated to control the technological conditions of silica-zinc crystalline glaze, and research on the technological conditions is an important subject in ceramic art and science. The artistic effect of silicon, zinc, and magnesium crystalline glaze is influenced by many factors, scientific and reasonable glaze composition and glaze application method are the basis of crystal formation, firing condition is the key to controlling crystal flower, and the colorant is the key factor of color presentation. This paper introduces the preparation process of crystalline art glaze of silicon, zinc, and magnesium, discusses the key factors that affect the performance of crystalline glaze and crystal formation, and determines the best glaze application method and firing technology.
The effect of the coefficient of friction between the roller and the powder on the rolling process
Authors: Yin Quan-zhong , Li Xiao-qiang , Liang Yong-ren , Li Rong , Ren Shang-yuan , Kang Zhi-Xin
Published: December 2022

The friction coefficient between the roller and the powder is one of the important factors affecting the rolling process. Since the friction coefficient is difficult to measure during rolling, it is usually regarded as a constant value in previous studies. However, the friction coefficient changes with the changes in process parameters such as the gap size and the rolling speed. In order to study the effect of the friction coefficient between the roller and the powder on powder rolling, the Drucker Prager Cap model for nickel powder rolling was established by ABAQUS. Firstly, the changes of contact stress (CPRESS) between the roller and the powder, the width (PE33), and relative density (SDV1) of the strip during rolling were analyzed. Then, the effect of the friction coefficient between the roller and the powder on the contact stress, the width, and the relative density of the strip was studied especially. The results show that during the rolling process, the contact stress remains basically unchanged. However, a large transverse deformation occurs on both sides of the strip, and the deformation in the middle is basically small. The relative density is greatest at the smallest seam between the rollers, and it decreases slightly after moving away from the roller, and then it remains stable. The coefficient of friction between the roller and the powder has an impact on the rolling result, in which the contact stress between the roller and the powder, the width, and the relative density of the strip will increase as the friction coefficient increases.
Defect detection of injection-molded parts based on improved-YOLOv5
Authors: Liang Haoming , Chen Jianrui , Xie Wei , Yu Xiaoyuan , Wu Weilin
Published: December 2022

Quality inspection with injection-molded parts (IMPs) is an essential part of the process of producing IMPs. To improve production quality, we propose an improved-YOLOv5 model to detect the object defection of the IMPs. Different from the original YOLOv5, we replace the coupled detection head (CH) with the independent decoupled head (IDCH), while adding the Squeeze-and-Excitation attention mechanism (SE) into the regression branch. Furthermore, a defective dataset of IMPs is constructed within the real-world production line, including 1357 IMPs images. The experimental results demonstrate the effectiveness of the improve-YOLOv5. Compared with YOLOv5, the precision and recall of the modified algorithm in this paper are increased by 2.5 % and 4.7 %, respectively. For difficult categories, precision and recall are increased by 8.7 % and 13.5 %, respectively.
Study of interface monitoring technology for bored concrete infill piles
Authors: Tong Zhifeng , Zhang Dexiang , Zhou Xu , Chen Bin , Zhang Hong
Published: December 2022

Bored piles have been widely used in highway, railway, and other structural engineering foundations due to their mature construction technology, high bearing capacity, and wide range of applications. Inaccurate positioning of the concrete filling interface in bored pile holes will easily lead to overfilling and other engineering diseases, resulting in material waste and cost increases. The current method of rope-tied hammer measurement is time-consuming, labor-intensive, and cannot accurately determine the concrete surface. In order to dynamically monitor the concrete grouting interface, this paper develops a concrete grouting interface monitoring system based on the solid-liquid buoyancy principle, which determines the height of the grouting interface position by monitoring the buoyancy value and controls the motor forward and reverse working states to achieve the purpose of intelligent monitoring of concrete grouting interface. It solves the problem of overfilling or underfilling, realizes green construction and improves quality, and increases capital.
Analysis of stamping crack in bake hardening steel
Authors: Feng Huixiong , Huang Geng , Liu Xueli , Li Liejun
Published: December 2022

The bake hardening steel can better solve the contradiction between stamping formability and dent resistance of steel plates due to the lower strength and higher formability during stamping, as well as the advantages of increased strength after coating and baking. However, bake hardened steel can suffer from cracking problems in the stamping process. In this paper, the mechanical properties and stamping properties of the bake hardening steel were tested, and the production process was also analyzed. The results showed that the material has aged due to the long storage time, decreasing elongation. The main reason for stamping cracks was the reduction of the amount of oil applied to the material anti-rust oil. When the material was stored for a long time, the anti-rust oil on the surface of the steel plate volatilized, resulting in cracks in the stamping. Based on the above research, the material delivery time was strictly controlled. The cracks disappeared by supplementing and oiling the materials that had been stored for more than five months. The stamping performance of the bake hardening steel is improved.
Analysis and measures of rolling marks on hot galvanizing leveler
Authors: Zhang Kun , Yuan Jian , Feng Huixiong , He Chunyu
Published: December 2022

Hot-dip galvanized sheet is widely used in industries, such as automobiles, home appliances, electronic appliances and construction, due to its good corrosion resistance, processability, weldability, and paint ability. With the development of the automobile industry, the surface quality requirements of automobile steel are gradually improved. However, The galvanized sheet produced on our GJSS 2# galvanizing line often has rolling marks defects, which seriously affects the quality of products. This paper analyzed the physical and chemical features of the defect sample of roller marks on the sheet. Based on the research and analysis, measures such as adding side guide pulleys on the work roll chocks, high-pressure water spray was added to the lower backup rolls when changing rolls, and water barriers were added to the work roll tracks. The results showed that these measures reduced the occurrence of roll marks.
Design and analysis of Double-cavity micropump of flexible valve
Authors: Yan Ju , Dai Jietao , Li Liejun
Published: December 2022

Piezoelectric micropump and surface tension micropump are generally favored in industrial applications, but these two micropumps have obvious defects through industrial practice. Due to the presence of a piezoelectric oscillator, it is difficult to reduce the volume by optimization further, and the oscillator will be damaged to a certain extent after use for a long time. Based on electric wetting on dielectric (EWOD), a new, efficient EWOD-driven flexible valve micropump is designed using EWOD and flexible valves to replace the conical tube, and a dual microchannel structure is proposed to reduce flow fluctuations at the outlet. The working principle of the EWOD flexible valve micro-pump is deeply discussed. The micropump design is optimized by the finite element method, and its performance is analyzed. The numerical analysis results show that: (1) When the flexible valve structure is adopted, the micropump outlet flow increases significantly. (2) When using the double microchannel, the outlet flow fluctuation of the micropump is significantly reduced. (3) Using the structure of the double microchannel, the micropump has two internal rings, and the direction of the inner ring is related to the direction of the vibration droplet. The EWOD micropump structure is designed to solve the reflux phenomenon in the current micropump pumping process
Experimental study on forming process of the high-precision high-alkali glass tube
Authors: Li Zijin , Zhang Yang , Zhou You , Lv Xueliang , Hong Sheng , Li Kaiyu , Zheng Jingming
Published: December 2022

Rigid optical fiber products (optical fiber panels, image inverters, etc.) are a kind of image coupling and transmission device with excellent performance, which is formed by regular arrangement and fusion of tens of millions of optical fibers with a diameter of 3 to 6 μm. As the basic material for optical fiber, the high-alkali glass tube is one of the cores of optical fiber technology. The geometric parameters and precision of the high-alkali glass tube are completely determined by the molding process. This paper summarizes the influence of a single process parameter on the geometric parameters of the glass tube by studying the aspects of temperature, pressure in the tube, and traction speed, and systematically analyzes a large number of experimental data to establish an overall forming control theory, which provides a theoretical basis for actual production and proposes an improvement plan for high-precision high-alkali glass tube forming equipment to improve product quality.
On the correlation among ultra-fast quenching, retained ferrite content and strengthening mechanism in PC steel bars
Authors: Xiong Zhitao , Li Liejun , Peng Zhengwu , Gao Jixiang , Han Rongshuang
Published: December 2022

Prestressed Concrete (PC) steel bars made of 30MnSi are widely used in various prestressed components. This paper compared the hot-rolled, cold-drawn, quenched and tempered samples of PC steel bars, observed the microstructure evolution and hardness changes of steel bars in various processes, and studied the austenitizing process and mechanical properties at different quenching temperatures. The results show that there is a small amount of residual ribbon ferrite in the tempered microstructure, and the hardness of the quenched and tempered microstructure fluctuates locally, which may be related to the inhibition of ferrite recrystallization by rapid heating and the heterogeneity of carbon during austenitizing. With the increase of quenching temperature, the residual ferrite content decreases, and the tensile strength, hardness and yield ratio increase, while the plasticity decreases.
Effect of Testing Standard on Parameter Optimization of Fused Deposition Modelling Process
Authors: Gao Ge , Xu Fan , Xu Jiangmin
Published: December 2022

Fused deposition modeling (FDM) has emerged and spread worldwide as the most commonly used additive manufacturing (AM) technique. However, to this day, there has been no specific available guidance to evaluate the mechanical performance of FDM products quantitatively. The current approach to mechanical testing standards utilizes existing guidelines for testing materials, which may lead to a discrepancy in results. The topic of this article is to investigate three widely applied testing standards, namely ASTM, ISO, and GB, to analyze the impact of which on the tensile strength of FDM samples and in what amount. Polylactide (PLA) samples are prepared according to the three standards above. Four parameters (nozzle temperature, print speed, layer thickness, and raster width) with three levels are selected as control variables, and the Taguchi method is used for parametric optimization. Statistical analysis shows that the importance orders of parameters that affect the tensile performance as well as optimal levels for maximizing tension obtained based on different criteria are different. In addition, the results from ISO and GB samples are consistent, which are quite different from that of ASTM samples. The outcome of this study is helpful for the selection of testing standards in the FDM process and can make a reference for the experimental design for FDM users.
Influencing factors and conditions of increasing N in molten steel
Authors: Guo Dongdong , Li Huicheng , Chen Ting jun , Zhang JiaNin , Liu Sheng
Published: December 2022

N content has the important influence on the performance of rolled material and needs to be keep a watchful eye. However, the current N content control course is relatively simple and needs to be further studied. Starting from the full steel smelting course, through the analysis of the influence factors of increasing N in liquid steel and conditions, found that the main node control enhance of N in liquid steel and operating points, summed up the appropriate bottom blowing N gas pressure and flow rate, improve the control level of bottom blowing N and N content, the ability of N steel smelting in batches, ensure the quality of liquid steel meets the demand of high standard special steel, at the same time achieving production cost reduction.
Research on the low-pressure casting process of a double suction impeller in 304 austenitic stainless steel with high performance and thin-wall complex structure
Authors: Liu Yixiong , He Haiping , Gao Jixiang , Li Gang , Liang Yi , Li Liejun
Published: December 2022

The manufacturing of thin-wall complex castings using pressure-assisted casting is one of the most significant challenges for structural applications requiring excellent mechanical properties and fuel. In this paper, efforts have been made to manufacture thin-wall complex structure casting using high-temperature alloys with high strength. Low pressure casting forming process was used to manufacture a double suction impeller in 304 austenitic stainless steel with a thin-wall complex structure. By combining 3D printed sand mold with an optimized low-pressure casting process, a double suction impeller with a thin-wall thickness of 3mm was successfully prepared. The prepared double suction impeller showed structural integrity, smooth surface, and compact structure. The filling and solidification process of the 304 austenitic stainless-steel melts were analyzed using casting simulation software. The casting had an excellent mechanical property with a tensile strength of 595 MPa, yield strength of 265 MPa, and elongation of 48%. Results show that the improved low-pressure casting processes could be applied to the production of thin-wall complex structure parts during high-temperature casting processes. The results are of great significance to the casting of high-temperature alloys.
Corrosion resistance evaluation model for automobile
Authors: Wang Xin , Ren Kaixu , Xu Shujie , Wang Jiayu , Liu Peng
Published: December 2022

Based on corrosion big data and user demand, this paper provides a passenger car corrosion resistance evaluation model with strong practicability, operability, and good discrimination. Considering the three dimensions of time, the number of problems, and severity, the corrosion resistance of the whole vehicle is comprehensively evaluated through appearance, function (primary evaluation index), and coating scratch (bonus item), to reflect the advantages and disadvantages of automobile corrosion resistance with quantitative score value. It aims to provide a yardstick for evaluating the corrosion resistance of automobile products and technical support for reasonably improving the anti-corrosion quality of automotive products and help the industry effectively control the corrosion problems of passenger cars.
Numerical simulation study of corrosion behavior of Ni-P coating under multiple working conditions
Authors: Zuo Youxing , He Danna , Wang Shixin , Yu Ziyuan
Published: December 2022

The research on marine corrosion protection is very important in modern naval warfare. In this paper, combined with the working environment and usage requirements of underwater equipment, a 3D modeling is carried out based on a certain type of underwater equipment, and the model was divided into regions according to the difference between the base material, and the electrochemical corrosion protection was established through the finite element simulation software COMSOL Multiphysics. The simulation model was used to simulate and analyze the corrosion laws of various parts of the equipment under three different working conditions. According to the simulation results, the corrosion rate of the equipment under the protection of Ni-P chemical coating is much lower than the natural corrosion rate and the corrosion rate in seawater with a 30% concentration of Na2SO3 corrosion inhibitor, and the Ni-P chemical coating has a good anti-corrosion effect. This paper puts forward suggestions for the follow-up improvement and development of the corrosion protection research of this type of underwater equipment and provides a reference for the research on the corrosion behavior of other metals.
Smoke target detection based on dynamic multi-frame decimation with cavity convolution
Authors: Zheng Yuanpan , Niu Yiqing
Published: December 2022

Compared with traditional smoke alarms, smoke detection based on video images has the advantages of low cost, fast response time, wide applicability, etc. Smoke detection algorithms are becoming an effective and widely used tool for early warning of fires by recognizing smoke graphic features. In this paper, we use the VGG-16 neural network as the benchmark network and improve it by using null convolution and combining it with the dynamic multi-frame subtraction method for smoke detection. The experimental results show that the proposed method is useful for early warning of smoke in the early stage of a fire before it becomes intense.
Research on the three degrees of freedom hysteretic mechanical model of floating rafts
Authors: Zhang Zhenli , Qiang Lei , Wang Qiangyong , Ding Ding , Du Saipeng
Published: December 2022

A floating raft is a complicated multilayer vibration isolation system, which is often simplified as a two-degree-of-freedom viscous damping system in analysis. In order to research the influences of the hysteretic damping and the raft flexibility on the vibration isolation effect, a three-degree of freedom hysteretic mechanical model of the floating raft is established, and the impedance method is adopted to deduce the model of the force transmissibility of the floating raft. The analytic calculation methods of force transmissibility are given aiming at the low-frequency range, the resonance range, and the high-frequency range, respectively. Finally, the influence rules of damping, mass, and stiffness on force transmissibility are analyzed aiming at the value range of parameters of most floating rafts. The main analysis conclusions are listed as follows: the analytic calculation equation for resonance frequency and resonance peak is accurate; the vibration isolation effect of the high frequency range is determined by the entire floating raft, the unconstrained raft, the inherent frequency of the equipment, the mass ratio between the raft and the equipment only; the hysteretic damping can reduce the force transmissibility at the place of the resonance frequency of the floating raft, which shall be maximized; the increase in the mass of the raft will reduce the force transmissibility during the frequency range above the inherent frequency of the equipment, but it will reduce the marginal benefit; the reduction in the stiffness of the isolator or the raft will reduce the force transmissibility during the frequency range above the inherent frequency of the equipment, and will increase the displacement of the equipment; with limited displacement, it is better to design the isolator and the raft according to the principle of equal stiffness.
Centrifugal casting simulation and physical field analysis of ZL107
Authors: Liu Tianze , Ban Chunyan , Le Qichi , Zhao Dazhi , Kang Jianming
Published: December 2022

Centrifugal casting is one of the commonly used production methods for cylinder liner preparation. Al-Si-Mg centrifugal casting alloys have been extensively studied and applied, but as the matrix material, its mechanical properties still cannot meet the service requirements in a severe working environment with high strength, large load, or high temperature. Therefore, most Al-Si-Mg centrifugal casting alloys can only bear medium and low loads and operate in an environment below 150 °C. It has greatly restricted the development of industrial and civil fields. In this paper, ZL107 alloy was taken as the research object and Fluent 2021R1 simulation software was used to explore the filling characteristics of Al-Si-Cu alloy under centrifugal casting conditions. When the casting temperature was 770 °C, the initial casting temperature was 230 °C, the rotation speed was 1400 rpm and the casting speed was 0.45 m/s, the casting filling and solidification processes were analyzed based on the temperature field and velocity field. The test shows that there are large temperature differences between the outer surface and the inner surface of the casting, axial and radial, which are the parts where defects exist. The approximate area of the defect is estimated, which has a certain guiding role.
Research on size coupling and sensitivity analysis of SAR antenna truss rod
Authors: Li Yun , Zeng Ting , Chen Ling , Zhang Zhiqiang , Liu Jianze , Chen Lihui
Published: December 2022

To eliminate the influence of the size coupling of SAR antenna truss rod on assembly accuracy, this paper defines the assembly sequence, part datum, tolerance, assembly operation, and measurement operation of the model by establishing the tolerance analysis model of the assembly dimension chain and measurement target. The assembly simulation process of the deployment mechanism is simulated, the plane deviation of the antenna panel of the deployment mechanism is analyzed, and the contribution and sensitivity data of each component ring size to the closed ring size are obtained. The simulation results show that the in-plane angle error of the antenna panel is mainly affected by the length of the component ring rod. By focusing on controlling the dimensional tolerance of the truss rods with high sensitivity, the assembly accuracy of the antenna deployment system can be guaranteed. Sensitivity is the magnification of assembly deviation by the transmission of deviation source, which reflects the influence of the change of composition tolerance on the change of functional requirements. According to the sensitivity analysis, the key dimensions that affect assembly accuracy can be obtained. The assembly requirements of high-quality and low-cost products can be achieved by strictly controlling the dimensional tolerance of key components and relaxing the tolerance of non-key components.
Modeling and driving function optimization of tree climbing robot
Authors: Yang Xi , Pan Songbo , Wang Jichen , Liu Rui , Li Wenhui
Published: December 2022

To ensure the tree-climbing robot can complete the up-tree or down-tree process, its arms need to adjust the displacement of the push rod in real-time according to the diameter size of the tree trunk so that the tire can smoothly bypass the smaller tree pile. However, the irregular shape of the trunk surface makes the inflatable tire vibrate during rolling, which will reversely affect the performance of the push rod. Based on this, the three-dimensional model of the tree-climbing robot is established by Solid Works software, and the kinematics simulation model of the tree-climbing robot is established by Automatic Dynamic Analysis of Mechanical Systems (ADAMS). The kinematics simulation analysis is carried out. According to the tire displacement curve of the tree-climbing robot, the optimal solution of the push rod driving function is solved. Under the condition of ensuring the trajectory of the spiral rise is unchanged, the mean square deviation of the distance between the two arms of the tree-climbing robot is the smallest, and the push rod is the least affected by the reverse effect of the tire. The simulation results show that under the condition of the optimal solution, the frequency distribution and amplitude of the four springs are basically the same. The force of the four springs is uniform, and the reverse influence of the tires on the two push rods is minimized, which is conducive to the improvement of the stability of the tree climbing robot.
Mechanical properties of aluminium alloy 6082-T6 plate and butt weld joint: Experimental test, numerical modelling and application
Authors: Cui Xintao
Published: December 2022

Aluminium alloy has high mechanical properties and is widely used in manufacturing vehicles to reduce weight. This paper describes an experimental and numerical study of the mechanical properties of aluminium 6082-T6 plates and butt weld joints. Experiments were conducted on three 6082-T6 plates and three butt weld joint specimens, and then stress-strain curves were obtained and analyzed. Finite element (FE) models were developed and validated against the test results. Based on the test and numerical data, the application of the strength analysis of an electrical commercial truck frame with aluminium 6082-T6 using the finite element method was illustrated. The results show that compared with the base metal, the tensile strength of the butt weld joint is significantly reduced since the welding heat affected zone became a weak part of the joint. The results of the case study show that strength analysis of the truck frame with aluminium 6082-T6 using the FE method can be performed based on mechanical performances obtained in this study.
Numerical simulation analysis of high-speed asynchronous motor based on Fe-based amorphous alloy and SMC stator
Authors: Zhu Feng , Zhang Jiahao , Wang Jinghui , Zhou Feng , Sun Haibo
Published: December 2022

Due to its unique advantages of small size, high power density, and high efficiency, high-speed asynchronous motor (HSAM) has been widely used in aerospace, high-speed air compressor, and other advanced manufacturing equipment. Based on a developed finite element model validated by a prototype motor testing platform, the influence of stators made of different magnetic materials on the efficiency of the HSAM with a rated speed of 7500 rpm has been systematically investigated. Hereinto, the magnetic materials are silicon steel, Fe-based amorphous alloy, and SMC. Compared with silicon steel, the iron loss of HSAM can be significantly reduced by 91.1% using the stator made of Fe-based amorphous alloy in the frequency range of 0-800 Hz, while the SMC motor exhibits an advantage in lower loss when the frequency over 157.28Hz.
An FSPCA-BP algorithm and its application to aircraft overhaul makespan prediction problem
Authors: Fu Shifeng , Jia Xiaoliang , Huang Mingjun , Chang Xiao
Published: December 2022

The implementation strategy for meticulous production management of aircraft overhaul is facing barriers, such as the lack of an effective method that can achieve accurate prediction of makespan in the whole aircraft overhaul process. In this paper, a novel prediction method for makespan of aircraft overhaul by extending feature selection principal component analysis (FSPCA) and backpropagation (BP) neural network (FSPCA-BP) is proposed. Firstly, the FSPCA algorithm is developed to achieve feature selection and dimension reduction simultaneously. Then, the principal components factors obtained from the FSPCA algorithm are used as the input vectors for the BP neural network to predict the makespan of aircraft overhaul. Finally, the proposed method is demonstrated and tested in an application scenario of a partner company and is further compared with PCA-BP and BP approaches, respectively. The result shows that the FSPCA-BP approach has higher accuracy than PCA-BP and BP approaches in aircraft overhaul makespan prediction. Finally, the managerial implications of the proposed method for shop-floor departments are discussed in detail.
AgNWs decorated laser-induced graphene heater for performance enhancement
Authors: Zhu Congcong , Tao Lu-Qi , Zou Simin , Sun Hao , Guo Liangyan , Sang Tianyi
Published: December 2022

Film heaters are attracting growing attention as promising wearable electronic skin for a multitude of applications. Elastomer transfers laser-induced graphene (LIG) is a popular approach to preparing stretchable film heaters; however, they fall short of performance. Here, silver nanowires (AgNWs) were employed to decorate polydimethylsiloxane (PDMS) transferring LIG by using CO2 infrared laser direct-writing technology. This heater’s electrothermal performance was substantially enhanced at different voltages, with a 35.28% enhancement when the voltage was 12 V. And response and recovery times were also improved. The results of repeated heating and cooling cycles also showed long-term reproducibility and reliability. The better performance could be attributed to the strengthened connection between the porous holes after long AgNWs coating on the porous structure of LIG, consequently enhancing the film conductivity. PDMS transferring LIG/AgNws have the extensive potential for future applications in artificial intelligence.
Low-energy electron scattering facilities in Japan
Authors: Suda Toshimi
Published: December 2022

This article reports our research activities of low-energy electron scattering facilities in Japan: the ULQ2 facility for proton charge measurements at Tohoku and the SCRIT facility for the exotic nuclei at RIKEN.
Searches for dark photons at accelerators
Authors: Hearty Christopher
Published: December 2022

Dark sector models attempt to describe observed dark matter properties, as well as other anomalies such as muon (g − 2), possible violations of lepton universality in B decay, and the possible observation of a new particle by the ATOMKI experiment. There is an extensive program of operating and proposed experiments to search for the new, low-mass, feebly-interacting particles predicted by such theories. I will focus on current searches at accelerators for dark photons, a component of many dark sector models. The results are interpreted in a basic model containing dark photons and dark matter.
Lepton Universality Test with MUSE at PSI
Authors: Kohl Michael
Published: December 2022

Lepton universality (LU) typically refers to the lepton coupling, which is considered to be the same for e, μ, and τ leptons, if the interaction is electroweak according to the Standard Model, and it is hence a compelling probe for New Physics. The same principle of universal electroweak lepton interaction leads to the expectation that lepton scattering yields are equal for e and μ beams under the same kinematic condition. The mere mass difference between e and μ affects kinematic quantities (such as the relation between scattering angle and Q
2), and the lepton mass dependence of elastic cross sections for leptons scattered from structured and pointlike objects are taken into account. By comparing e
+, e
−, μ
+, and μ
− scattering yields, two-photon exchange (TPE) effects, universal or not, can be separated from the general LU test of the e/μ yield ratio. With its separable mixed beams of e
+/μ
+ and e
−/μ
−, respectively, the MUSE experiment at PSI is not only designed to measure the proton charge radius with four lepton species, but is also uniquely suited to probe TPE and LU, while benefitting from partial cancellations of certain shared systematics. An overview will be given of the MUSE experiment, the sensitivity, and the present status.
Diagnostic Tests as an Important Pillar in Today’s Physics Learning: Four-tier Diagnostic Test a Comprehensive Diagnostic Test Solution
Authors: Istiyono E
Published: December 2022

This study aims to describe the urgency and development of diagnostic tests starting from the 1-tier test to the 4-tier test. The form of diagnostic tests is always evolving, starting from the 1-tier test (answer only), 2-tier test (answers and reasons), 3-tier test (answers, reasons, and confidence level), up to 4-tier tests (answers, level of confidence in answers, reasons, and level of confidence in reasons). The results of the study show that the more tiers used in the assessment instrument, the more aspects that can be analyzed. The analysis of the 1-tier test depends on the construct of the questions developed. The 2-tier test analysis can be grouped into three categories: understanding concepts, misconceptions, and not understanding concepts. The 3-tier diagnostic test can classify students into six categories, namely; SC, FP, FN, MSC, Lucky Guessing, and LK. Analysis of the four-tier diagnostic test (FTDT) can produce eight or sixteen categories. However, the optimal analysis of FTDT applies to eight categories, namely; SC, LK type 1, FP, LK type 2, FN, LK type 3, MS and LK type 4. The implication of the research is the optimal diagnostic test for diagnosing students' level of understanding of Physics is FTDT, with an analysis of eight categories. FTDT is more meaningful because the results of the diagnosis are accompanied by suggestions for a follow-up to overcome learning difficulties for each student.
Web Learning Research in Physics Education During the COVID-19 Pandemic
Authors: Prahani B K , Jatmiko B , Amelia T , Pristianti M C , Mahtari S , Uulaa R F R
Published: December 2022

Physics education can be given effectively even in an emergency such as the COVID-19 pandemic with the help of existing technology. This study aims to analyze the trend and contribution of web learning in physics education during the COVID-19 pandemic from 2020 to 2021. The research method used is bibliometric analysis and literature review. This study uses data from Scopus, and the keyword is web learning in physics education, 361 documents were found. Then filtered for 2020-2021 and found 43 documents analyzed using Ms. Excel and VOSViewer. From this research, it can be concluded that: 1) The most widely used keywords are student and website, the country that contributes the most is Indonesia, 2) The most common type of document is conference paper, 3) Web learning research has contribution in physics education including: can improve student learning outcomes, understanding and motivation, web learning can be applied to physics laboratory services. The limitation of this research is that it only uses one database to obtain research data. Future web learning research in physics education needs to be carried out and developed more intensely using other databases besides Scopus.
The Influence of Quantum Teaching Model through the TANDUR Strategy on the Students’ Learning Outcome of Senior High School Students in Static Fluid Materials
Authors: Allo A Y T , Farida I , Sinon I L S
Published: December 2022

This research was conducted to determine the effect of the quantum teaching model through the TANDUR strategy on the cognitive learning outcomes of students and the psychomotor learning outcomes of students in class XI Science before and after treatment using the quantum teaching model through the TANDUR strategy. The instruments used were tests in the form of pretest and posttest to measure cognitive and observation sheets to measure psychomotor. This research method is Experimental Design (pre-experimental), with the research design used as the one group pretest-posttest design strategy. Data analysis using the application Facets, Ms Excel and SPSS 22. The population, namely students of class XI Science YAPIS Manokwari High School academic year 2020/2021, amounts to 16 people. This study's results indicate an influence on the use of quantum teaching models through the TANDUR strategy. The value of psychomotor learning outcomes shows that the influence of the quantum teaching model through the TANDUR strategy can improve learning outcomes in the classroom. Overall students are at very high criteria, 75%-87% and the average value of psychomotor learners’ experience improvement at each meeting. This research implies that students' cognitive and psychomotor abilities have increased significantly, and students enjoy learning physics.
Development of Physics Learning Instrument using Guided Inquiry Model as Effort to Increase Student Learning Result on Dynamic Fluid Learning Material at Senior High School
Authors: Sumo M , Jatmiko B , Supardi Z A I , Arifin S , Nasrullah  , Mukit A
Published: December 2022

This study intends to generate a valid, practical and effective guided inquiry model of Physics learning instruments to increase the results of senior high school students. The learning material was developed based on Kemp with steps: 1) topic and goal, 2) student characteristics, 3) study goals, 4) content, 5) preliminary research, 6) source of learning activities, 7) support service, 8) evaluation. The instrument was tested to eleven grades eleven in the second semester with a pre-experimental one-group pretest-posttest design. Study data was collected through observation, tests and questionnaires. The study revealed that revised learning instruments were valid. Practicability level of learning instrument based on lesson plan practicability were in good category and fulfill the guided inquiry model syntax. Instrument effectiveness could be seen from an Increase in student ability in concept understanding, as shown by N-gain with a high category in 0.81 value; Positive students respond to learning instrument and learning activity, in which 96% responded positively, and 4% responded negatively. Based on the study finding, it was concluded that student learning results shown by student concept comprehension, psychomotor skill, and character that consist of discipline and responsibility increased upon the implementation of learning instrument developed by the guided inquiry model on dynamic fluid learning material. This research implies that the development of physics learning tools will have a positive impact on increasing students' abilities in learning physics on dynamic fluid topics.
Exploring Inquiry Skills During Home Experiments about Science in the Online Instruction
Authors: Supeno  , Ridlo Z R , Setiawan A M
Published: December 2022

Inquiry is an essential skill in science learning which includes designing, conducting, and interpreting the results of scientific investigations. Inquiry skills are usually taught by applying instruction by doing science-based education. Experiments are essential in training students' inquiry skills in science learning. Online science learning is effectively used to teach theoretical or conceptual material and becomes a challenge when applied in education that provides practical experience in the laboratory by involving experiments methods with hands-on exercises. This study tried online science learning by integrating experimental activities using hands-on activities carried out by students in their respective homes. During science lessons, students choose a topic about science and conduct experiments at home. Students design experiments, collect data, analyze data, and formulate conclusions to construct scientific knowledge. The results showed that practical activities carried out at home in online science learning could help students develop their inquiry skills. Students can carry out scientific investigations by applying various inquiry skills to obtain valid scientific knowledge.
Teaching Physics in Scientific Information Disclosure Era Through Daily Physics Learning
Authors: Kristiyanto W H
Published: December 2022

Daily physics is the study of physics that raises problems and applications in everyday human life. This study aims to describe the structure of physics learning in everyday life that supports physics learning in the era of scientific information disclosure and its implementation. This qualitative descriptive research was conducted by examining the structure of everyday physics learning and observing the responses of research subjects with physics and social backgrounds who participated in the daily physics lessons. The results of this study indicate that the structure of learning physics in everyday life is designed to be followed by all participants from both exact and non-exact groups as part of the Whole Person Education program. Subjects with a background in Physics explain daily physics learning followed by discussions based on popular events in everyday life that are studied from the physics side easily and strengthen the understanding of physics concepts that they already have. Subjects with social backgrounds explain daily physics learning, followed by presenting examples that occur in everyday life, such as birthday balloons that can be attached to walls and others. These examples can be easily accepted and understood by all participants. However, participants with social backgrounds find it quite difficult when the discussion enters the discussion of abstractions such as equations and formulas. This research concludes that the structure of everyday physics is very supportive of learning physics for many people in the era of scientific information disclosure.