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A comprehensive research on wear resistance of GH4169 superalloy in longitudinal-torsional ultrasonic vibration side milling with tool wear and surface quality

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Chinese Journal of Aeronautics 2024年第4期37卷 556-573页

作者： Baoqi CHANG Zhaoxi YI Fen ZHANG Lian DUAN Ji-an DUAN School of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China State Key Laboratory of High Performance and Complex Manufacturing Central South UniversityChangsha 410083China School of Physics and Electronics Central South UniversityChangsha 410083China

To improve the service and machining performance of the workpiece, the tool wear mechanisms, surface machining quality, and wear resistance in conventional side milling(CSM)and longitudinal-torsional ultrasonic vibration side milling(LTUVSM) of GH4169 superalloy at different cutting lengths are investigated systematically. Tool wear mechanisms are revealed and the correlation between machined surface quality with tool wear is analyzed correspondingly. Tool wear patterns mainly include adhesive wear, diffusion wear, abrasive wear, and chipping sticking.Better surface quality is achieved in LTUVSM due to a maximum reduction of flank wear bandwidth and wear rate by 71.9% and 71.5%, respectively, compared to CSM. The friction coefficient,initial wear stage time, and wear volume of dry sliding wear were measured to evaluate the workpiece wear resistance. The maximum reductions in friction coefficient and wear volume in LTUVSM are 18.2% and 15.8% compared to CSM. The regular ultrasonic vibration textures suppress the friction and the growth of contact nodes in the contact area, decreasing the degree of surface wear, which is demonstrated by a 38.8% increase in initial wear stage time compared to CSM.In conclusion, the workpiece in LTUVSM exhibits higher wear resistance because of the improvement of tool wear and the guarantee of surface quality.

关键词： Dry sliding wear Surface quality Tool wear ultrasonic vibration Wear resistance

Application of ultrasonic vibration to shape-casting based on resonance vibration analysis

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China Foundry 2023年第4期20卷 339-346页

作者： Zong-hang Han Zhi-ming Wang Zhi-ping Sun Bing-rong Zhang Wei-feng Rao School of Mechanical Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Jinan Shengquan Group Jinan 250204China

The application of ultrasonic vibration during the casting process has been proven to refine the microstructure and enhance the properties of the casting.By using the direct inserting method,wherein the ultrasonic horn is inserted directly into the melt,ultrasonic treatment can be utilized in the semi-continuous casting process to produce aluminum ingots with simple shapes.However,due to the attenuation of ultrasound,it is challenging to apply the direct inserting method in the die casting process to produce complex castings.Thus,in this study,the impact of ultrasonic vibration on the microstructure of a gravity die-cast AlSi9Cu3end cap was investigated by applying ultrasonic vibration on the core(indirect method).It is found that the effect of ultrasonic vibration relies greatly on the resonance mode of the core.Selection of ultrasonic vibration schemes mainly depends on the core structure,and only a strong vibration can significantly refine the microstructure of the casting.For castings with complex structures,an elaborated ultrasonic vibration design is necessary to refine the microstructure of the specified casting.In addition,strong vibration applied on the feeding channel can promote the feeding ability of casting by breaking the dendrites during solidification,and consequently reduce the shrinkage porosity.

关键词： resonance mode ultrasonic vibration feeding channel aluminum alloy casting

Rheological model of semisolid Mg_(2)Si/AM60 composites prepared by ultrasonic vibration treatment

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Rare Metals 2022年第8期41卷 2783-2788页

作者： Yuan-Sheng Rao Hong Yan Jun Wan Department of Materials Processing Engineering School of Mechanical and Electrical EngineeringNanchang UniversityNanchang330031China Key Laboratory of Light Alloy Preparation and Processing in Nanchang City Nanchang330031China

The rheological behavior of semisolid Mg_(2)Si/AM60 composites prepared by ultrasonic vibration treatment was investigated.The effects of primaryα-Mg solid content,the ultrasonic power and the content of reinforcement phase Mg_(2)Si on the apparent viscosity of semisolid composites were discussed.The results show that the apparent viscosity of the semis olid composites increases with the increase in a-Mg solid content.Meanwhile,the apparent viscosity decreases with the increase in ultrasonic power,and the reduction amplitude is higher when the solid content is higher.In addition,the apparent viscosity increases with the increase in Mg_(2)Si content.Based on experimental data fitting,the rheological model of semisolid Mg_(2)Si/AM60 composites prepared by ultrasonic vibration was established.

关键词： Semisolid Magnesium matrix composites ultrasonic vibration Apparent viscosity

Plastic deformation of magnesium alloy with different forming parameters during ultrasonic vibration-assisted single-point incremental forming

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Rare Metals 2022年第11期41卷 3878-3886页

作者： Chun Jian Su Ting Ting Xu Ke Zhang Ke Zhang Shu Mei Lou Qing Wang College of Mechanical and Electronic Engineering Shandong University of Science and TechnologyQingdao266590China

The research of forming parameters on the ultrasonic vibration single-point incremental forming of magnesium alloy plastic deformation can provide a theoretical basis for the establishment of the forming parameters.According to the forming characteristics of magnesium alloy sheet,a new method of ultrasonic vibration-as sis ted single-point incremental forming was proposed.The influence of forming parameters on the plastic deformation of magnesium alloy was studied by finite element simulation and experimentation.The influence of vibration frequency,amplitude,friction coefficient,and tool head size on stress and thinning rate of magnesium alloy during ultrasonic vibration-as sis ted single-point asymptotic forming was studied.The results show that the vibration frequency of 20 kHz and forming tool radius of about 5 mm are beneficial for plastic deformation magnesium alloy in ultrasonic vibration-assisted single-point incremental forming.With vibration amplitude increasing,the maximum shear stress tends to decrease as a whole,but at the amplitude of 0.16 mm,the thinning rate is large and fracture occurs easily.With friction coefficient increasing,the maximum shear stress tends to increase,and there is a good linear relationship between the maximum thinning rate and the friction coefficient.

关键词： Magnesium alloy ultrasonic vibration Incremental forming Forming parameters Plastic deformation

Microstructure and mechanical properties of magnesium matrix composite reinforced with carbon nanotubes by ultrasonic vibration

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Rare Metals 2022年第7期41卷 2331-2336页

作者： Cheng-Dong Li Xiao-Jun Wang Wei-Qing Liu Ku Wu Hai-Long Shi Chao Ding Ming-Yi Zheng School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

A novel approach was successfully developed to fabricate bulk carbon nanotube-reinforced Mg matrix com-posites with uniform carbon nanotubes(CNTs).The approach consists of pre-dispersion and ultrasonic vibration.Homoge-neous and single CNTs on flake Zn powder can be achieved simply by slurry blending.The pre-dispersed CNTs were added to Mg melt,and then,the melt was ultrasonically pro-cessed.After ultrasonic vibration,the CNTs/Mg-6Zn melt was cast into a metal mold.Most CNTs distribute homoge-neously and singly in the bulk composites.Moreover,good interfacial bonding is achieved,and Raman spectroscopy analysis shows that the damage to CNTs is insignificant.Meanwhile,CNTs evidently improve the ultimate tensile strength,yield strength and elongation.The Kelly-Tyson formula agrees well with the experimental tensile value,and the load-transfer efficiency is nearly equal to 1.

关键词： Magnesium matrix composite Carbon nanotubes ultrasonic vibration Microstructure Mechanical properties

Influence of non-uniform ultrasonic vibration on casting fluidity of liquid aluminum alloy

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China Foundry 2022年第5期19卷 380-386页

作者： Zi-heng Han Zhi-ming Wang Zhi-ping Sun Bing-rong Zhang Wei-feng Rao School of Mechanical Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China

The application of ultrasonic vibration to the casting process can be realized through mould(die)vibration.However,the resonant vibration of the mould is always accompanied by a non-uniform vibration distribution at different parts,which may induce a complex liquid flow and affect the casting fluidity during the mould filling process.The influence of non-uniform ultrasonic vibration on the fluidity of liquid AlSi9Cu3 alloy was studied by mould vibration with different vibration gradients.It is found that ultrasonic mould vibration can generate two opposite effects on the casting fluidity:the first,ultrasonic cavitation in melt induced by mould vibration promotes the casting fluidity;the second,the non-uniform mould vibration can induce a melt flow toward the weak vibration areas and turbulence there,consequently decreasing the casting fluidity.When the melt flow and turbulence are violent enough to offset the promoting effect of cavitation on fluidity,the ultrasonic vibration will finally induce a resultant decrease of casting fluidity.The decreasing effect is proportional to the vibration gradient.

关键词： ultrasonic vibration vibration gradient aluminum alloy fluidity

Comparative analysis of single-crater parameters in ultrasonic-assisted and unassisted micro-EDM of Ti6Al4V using discharge plasma imaging

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Nanotechnology and Precision Engineering 2024年第2期7卷 11-24页

作者： Sohaib Raza Chandrakant Nirala Department of Mechanical Engineering Indian Institute of Technology RoparPunjab 140001India

ultrasonic-assisted micro-electro-discharge machining(EDM)has the potential to enhance processing responses such as material removal rate(MRR)and surface finish.To understand the reasons for this enhancement,the physical mechanisms responsible for the individual discharges and the craters that they form need to be explored.This work examines features of craters formed by single discharges at various parameter values in both conventional and ultrasonic-assistedEDM of Ti6Al4V.High-speed imaging of the plasma channel is performed,and data on the individual discharges are captured in real-time.A 2D axisymmetric model using finite element software is established to model crater formation.On the basis of simulation and experimental results,a comparative study is then carried out to examine the effects of ultrasonic vibrational assistance on crater geometry.For every set ofEDM parameters,the crater diameter and depth from a single discharge are found to be higher in ultrasonic-assistedEDM than in conventionalEDM.The improved crater geometry and the reduced bulge formation at the crater edges are attributed to the increased melt pool velocity and temperature predicted by the model.

关键词： ultrasonic vibration Discharge crater Plasma diameter Single discharge

ultrasonic vibration assisted tungsten inert gas welding of dissimilar metals 316L and L415

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International Journal of Minerals,Metallurgy and Materials 2020年第7期27卷 943-953页

作者： Hong-xia Lan Xiu-fang Gong Sen-feng Zhang Liang Wang Bin Wang Li-ping Nie School of New Energy and Materials Southwest Petroleum UniversityChengdu 610500China State Key Laboratory of Long-life High Temperature Materials Dong Fang Turbine Co.Ltd.Deyang 618000China China National Erzhong Group Deyang Wanhang Die Forging Co. Ltd.Deyang 618000China School of Engineering Southwest Petroleum UniversityNanchong 637800China

ultrasonic vibration assisted tungsten inert gas welding was applied to joining stainless steel 316 L and low alloy high strength steel L415.The effect of ultrasonic vibration on the microstructure and mechanical properties of a dissimilar metal welded joint of 316 L and L415 was systematically investigated.The microstructures of both heat affected zones of L415 and weld metal were substantially refined,and the clusters ofδferrite in traditional tungsten inert gas(TIG)weld were changed to a dispersive distribution via the ultrasonic vibration.The ultrasonic vibration promoted the uniform distribution of elements and decreased the micro-segregation tendency in the weld.With the application of ultrasonic vibration,the average tensile strength and elongation of the joint was improved from 613 to 650 MPa and from 16.15%to31.54%,respectively.The content ofΣ3 grain boundaries around the fusion line zone is higher and the distribution is more uniform in the ultrasonic vibration assisted welded joint compared with the traditional one,indicating an excellent weld metal crack resistance.

关键词： ultrasonic vibration dissimilar metal welding microstructure mechanical properties micro-segregation electron backscatter diffraction

The influence of ultrasonic vibration on parts properties during incremental sheet forming

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Advances in Manufacturing 2021年第2期9卷 250-261页

作者： Yan-Le Li Zi-Jian Wang Wei-Dong Zhai Zi-Nan Cheng Fang-Yi Li Xiao-Qiang Li Key Laboratory of High Efficiency and Clean Mechanical Manufacture Ministry of EducationSchool of Mechanical EngineeringShandong UniversityJinan 250061People’s Republic of China National Demonstration Center for Experimental Mechanical Engineering Education Shandong UniversityJinan 250061People’s Republic of China School of Mechanical Engineering and Automation Beihang UniversityBeijing 100083People’s Republic of China

The integration of ultrasonic vibration into sheet forming process can significantly reduce the forming force and bring benefits including the enhancement of surface quality,the enhancement of formability and the reduction of spring-back.However,the influencing mechanisms of the high-frequency vibration on parts properties during the incremental sheet forming(ISF)process are not well known,preventing a more efficient forming system.This paper comprehensively investigates the effects of different process parameters(vibration amplitude,step-down size,rotation speed and forming angle)on the micro-hardness,minimum thickness,forming limit and residual stress of the formed parts.First,a series of truncated pyramids were formed with an experimental platform designed for the ultrasonic-assisted incremental sheet forming.Then,microhardness tests,minimum thickness measurements and residual stress tests were performed for the formed parts.The results showed that the surface micro-hardness of the formed part was reduced since the vibration stress induced by the ultrasonic vibration within the material which eliminated the original internal stress.The superimposed University,Beijing 100083,People’s Republic of China ultrasonic vibration can effectively uniform the residual stress and thickness distribution,arid improve the forming limit in the case of the small deformation rate.In addition,through the tensile fracture analysis of the formed part,it is shown that the elongation of material is improved and the elastic modulus and hardening index are decreased.The findings of the present work lay the foundation for a better integration of the ultrasonic vibration system into the incremental sheet forming process.

关键词： Incremental sheet forming(ISF) ultrasonic vibration Residual stress Forming limit