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Towards Sustainable Grinding of Difficult-to-Cut Alloys-A Holistic Review and Trends

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Chinese Journal of Mechanical engineering 2024年第2期37卷 1-28页

作者： Ning Qian Jiajia Chen Aqib Mashood Khan Biao Zhao Yurong Chen Wenfeng Ding Yucan Fu Jiuhua Xu Jiangsu Key Laboratory of precision and Micro-manufacturing Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Mechanical and Electronic engineering Nanjing Forestry UniversityNanjing 210037China JITRI Institute of precision manufacturing Nanjing 211805China

Grinding,a critical precision machining process for difficult-to-cut alloys,has undergone continual technological advancements to improve machining ***,the sustainability of this process is gaining heightened attention due to significant challenges associated with the substantial specific grinding energy and the extensive heat generated when working with difficult-to-cut alloys,renowned for their exceptional physical and mechanical *** response to these challenges,the widespread application of massive coolant in manufacturing industries to dissipate grinding heat has led to complex post-cleaning and disposal ***,in turn,has resulted in issues such as large energy consumption,a considerable carbon footprint,and concerns related to worker health and safety,which have become the main factors that restrict the development of grinding *** paper provides a holistic review of sustainability in grinding difficult-to-cut alloys,encompassing current trends and future *** examination extends to developing grinding technologies explicitly tailored for these alloys,comprehensively evaluating their sustainability ***,the exploration delves into innovative sustainable technologies,such as heat pipe/oscillating heat pipe grinding wheels,minimum quantity lubrication,cryogenic cooling,and *** groundbreaking technologies aim to reduce dependence on hazardous coolants,minimizing energy and resource consumption and carbon emissions associated with coolant-related or subsequent disposal *** essence of these technologies lies in their potential to revolutionize traditional grinding practices,presenting environmentally friendly ***,future development trends and research directions are put forward to pursue the current limitation of sustainable grinding for difficult-to-cut *** paper can guide future research and development efforts toward more environmentally friendly

关键词： Grinding Sustainability Cooling Energy consumption Carbon footprint Difficult-to-cut alloys

Biomimetic soft robotic wrist with 3-DOF motion and stiffness tunability based on ring-reinforced pneumatic actuators and a particle jamming joint

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Science China(Technological Sciences) 2024年第3期67卷 774-790页

作者： HU TeTe LU XinJiang YI Jian WANG YuHui XU Du State Key Laboratory of precision manufacturing for Extreme Service Performance School of Mechanical and Electrical EngineeringCentral South UniversityChangsha 410083China

The human wrist, a complex articulation of skeletal muscles and two-carpal rows, substantially contributes to improvements in maneuverability by agilely performing three-degree-of-freedom(3-DOF) orienting tasks and regulating stiffness according to variations in interaction forces. However, few soft robotic wrists simultaneously demonstrate dexterous 3-DOF motion and variable stiffness;in addition, they do not fully consider a soft-rigid hybrid structure of integrated muscles and two carpal *** this study, we developed a soft-rigid hybrid structure to design a biomimetic soft robotic wrist(BSRW) that is capable of rotating in the x and y directions, twisting around the z-axis, and possessing stiffness-tunable capacity. To actuate the BSRW, a lightweight soft-ring-reinforced bellows-type pneumatic actuator(SRBPA) with large axial, linear deformation(η_(lcmax)=70.6%,η_(lemax)=54.3%) and small radial expansion(η_(demax)=3.7%) is designed to mimic the motion of skeletal muscles. To represent the function of two-carpal rows, a compact particle-jamming joint(PJJ) that combines particles with a membrane-covered ballsocket mechanism is developed to achieve various 3-DOF motions and high axial load-carrying capacity(>60 N). By varying the jamming pressure, the stiffness of the PJJ can be adjusted. Finally, a centrally positioned PJJ and six independently actuated SRBPAs, which are in an inclined and antagonistic arrangement, are sandwiched between two rigid plates to form a flexible,stable, and compact BSRW. Such a structure enables the BSRW to have a dexterous 3-DOF motion, high load-carrying ability,and stiffness tunability. Experimental analysis verify 3-DOF motion of BSRW, producing force of 29.6 N and 36 N and torque of2.2 Nm in corresponding rotations. Moreover, the range of rotational angle and stiffness-tuning properties of BSRW are studied by applying jamming pressure to the PJJ. Finally, a system combining a BSRW and a soft enclosing gripper is proposed to demo

关键词： pneumatic soft actuators particle jamming robotic wrist soft robotics stiffness-tunable

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Elliptical vibration chiseling:a novel process for texturing ultra-high-aspect-ratio microstructures on the metallic surface

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International Journal of Extreme manufacturing 2024年第2期6卷 449-467页

作者： Zhiwei Li Jianfu Zhang Zhongpeng Zheng Pingfa Feng Dingwen Yu Jianjian Wang State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084People’s Republic of China Beijing Key Laboratory of precision/Ultra-precision manufacturing Equipments and Control Department of Mechanical EngineeringTsinghua UniversityBeijing 100084People’s Republic of China Division of Advanced manufacturing Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055People’s Republic of China

High-aspect-ratio metallic surface microstructures are increasingly demanded in breakthrough applications,such as high-performance heat transfer enhancement and surface plasmon ***,the fast and cost-effective fabrication of high-aspect-ratio microstructures on metallic surfaces remains challenging for existing *** study proposes a novel cutting-based process,namely elliptical vibration chiseling(EV-chiseling),for the high-efficiency texturing of surface microstructures with an ultrahigh aspect *** conventional cutting,EV-chiseling superimposes a microscale EV on a backward-moving *** tool chisels into the material in each vibration cycle to generate an upright chip with a high aspect ratio through material *** to the tool’s backward movement,the chip is left on the material surface to form a microstructure rather than falling *** one microstructure is generated in one vibration cycle,the process can be highly efficient using ultrafast(>1 kHz)tool vibration.A finite element analysis model is established to explore the process mechanics of ***,a mechanistic model of the microstructured surface generation is developed to describe the microstructures’aspect ratio dependency on the process ***,surface texturing tests are performed on copper to verify the efficacy of *** micro ribs with a spacing of 1–10μm and an aspect ratio of 2–5 have been successfully textured on *** with the conventional EV-cutting that uses a forward-moving tool,EV-chiseling can improve the aspect ratio of textured microstructure by up to 40 *** experimental results also verify the accuracy of the developed surface generation model of ***,the effects of elliptical trajectory,depth of cut,tool shape,and tool edge radius on the surface generation of micro ribs have been discussed.

关键词： metallic microstructure high aspect ratio backward-moving cutting vibration cutting chiseling material deformation

Study on 6-DOF active vibration-isolation system of the ultra-precision turning lathe based on GA-BP-PID control for dynamic loads

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Advances in manufacturing 2024年第1期12卷 33-60页

作者： Bo Wang Zhong Jiang Pei-Da Hu department of precision Instrument Tsinghua UniversityBeijing100084People’s Republic of China Institute of Machinery manufacturing Technology China Academy of Engineering PhysicsMianyang621900SichuanPeople’s Republic of China

The vibration disturbance from an external environment affects the machining accuracy of ultra-precision machining *** active vibration-isolation systems(AVIS)have been developed based on static *** a vibration-isolation load changes dynamically during ultra-precision turning lathe machining,the system parameters change,and the efficiency of the active vibration-isolation system based on the traditional control strategy *** solve this problem,this paper proposes a vibration-isolation control strategy based on a genetic algorithm-back propagation neural network-PID control(GA-BP-PID),which can automatically adjust the control parameters according to the machining ***-isolation simulations and experiments based on passive vibration isolation,a PID algorithm,and the GA-BP-PID algorithm under dynamic load machining conditions were *** experimental results demonstrated that the active vibration-isolation control strategy designed in this study could effectively attenuate vibration disturbances in the external environment under dynamic load *** design is reasonable and feasible.

关键词： Ultra-precision diamond turning lathe Active vibration isolation Six degrees of freedom Dynamic load Genetic algorithm-back propagation neural network-PID(GA-BP-PID)control

Flexible head-following motion planning for scalable and bendable continuum robots

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Biomimetic Intelligence & Robotics 2024年第2期4卷 86-96页

作者： Te Li Guoqing Zhang Xinyuan Li Xu Li Haibo Liu Yongqing Wang State Key Laboratory of High-performance precision manufacturing School of Mechanical EngineeringDalian University of TechnologyDalian 116023China

Continuum robots,which are characterized by high length-to-diameter ratios and flexible structures,show great potential for various applications in confined and irregular *** to the combination of motion modes,the existence of multiple solutions,and the presence of complex obstacle constraints,motion planning for these robots is highly *** tackle the challenges of online and flexible operation for continuum robots,we propose a flexible head-following motion planning method that is suitable for scalable and bendable continuum ***,we establish a piecewise constant curvature(PCC)kinematic model for scalable and bendable continuum *** article proposes an adaptive auxiliary points model and a method for updating key nodes in head-following motion to enhance the precise tracking capability for paths with different ***,the article integrates the strategy for adjusting the posture of local joints of the robot into the head-following motion planning method,which is beneficial for achieving safe obstacle avoidance in local *** article concludes by presenting the results of multiple sets of motion simulation experiments and prototype *** study demonstrates that the algorithm presented in this paper effectively navigates and adjusts posture to avoid obstacles,meeting the real-time demands of online *** average time for a single-step solution is 4.41×10^(-5) s,and the average tracking accuracy forcircular paths is 7.8928mm.

关键词： Continuum robot Motion planning Scalable and bendable Head-following

Ag-doped CNT/HAP nanohybrids in a PLLA bone scaffold show significant antibacterial activity

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Bio-Design and manufacturing 2024年第2期7卷 105-120页

作者： Cijun Shuai Xiaoxin Shi Kai Wang Yulong Gu Feng Yang Pei Feng State Key Laboratory of precision manufacturing for Extreme Service Performance College of Mechanical and Electrical EngineeringCentral South UniversityChangsha 410083China Institute of Additive manufacturing Jiangxi University of Science and TechnologyNanchang 330013China College of Mechanical engineering Xinjiang UniversityUrumqi 830017China

Bacterial infection is a major problem following bone implant ***,poly-l-lactic acid/carbon nanotube/hydroxyapatite(PLLA/CNT/HAP)bone scaffolds possess enhanced mechanical properties and show good ***,wesynthesizedsilver(Ag)-dopedCNT/HAP(CNT/Ag-HAP)nanohybrids via the partial replacing of calcium ions(Ca2+)in the HAP lattice with silver ions(Ag+)using an ion doping technique under hydrothermal ***ﬁcally,the doping process was induced using the special lattice structure of HAP and the abundant surface oxygenic functional groups of CNT,and involved the partial replacement of Ca2+in the HAP lattice by doped Ag+as well as the in situ synthesis of Ag-HAP nanoparticles on CNT in a hydrothermal *** result-ing CNT/Ag-HAP nanohybrids were then introduced into a PLLA matrix via laser-based powder bed fusion(PBF-LB)to fabricate PLLA/CNT/Ag-HAP scaffolds that showed sustained antibacterial *** then found that Ag+,which pos-sesses broad-spectrum antibacterial activity,endowed PLLA/CNT/Ag-HAP scaffolds with this activity,with an antibacterial effectiveness of 92.65%.This antibacterial effect is due to the powerful effect of Ag+against bacterial structure and genetic material,as well as the physical destruction of bacterial structures due to the sharp edge structure of *** addition,the scaffold possessed enhanced mechanical properties,showing tensile and compressive strengths of 8.49 MPa and 19.72 MPa,***,the scaffold also exhibited good bioactivity and cytocompatibility,including the ability to form apatite layers and to promote the adhesion and proliferation of human osteoblast-like cells(MG63 cells).

关键词： Ag-doped Carbon nanotube/hydroxyapatite(CNT/HAP) Antibacterial properties Bone scaffold

Precipitates Generation Mechanism and Surface Quality Improvement for Aluminum Alloy 6061 in Diamond Cutting

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 150-159页

作者：王海龙 DENG Wenping 王素娟 State Key Laboratory of precision Electronic manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006China Guangdong Provincial Key Laboratory of Micro-Nano manufacturing Technology and Equipment School of Electromechanical EngineeringGuangdong University of TechnologyGuangzhou 510006China

To improve the surface quality for aluminum alloy 6061(Al6061) in ultra-precision machining, we investigated the factors affecting the surface finish in single point diamond turning(SPDT)by studying influence of the precipitates generation of Al6061 on surface integrity and surface *** on the Johnson-Mehl-Avrami solid phase transformation kinetics equation, theoretical and experimental studies were conducted to build the relationship between the aging condition and the type, size and number of the precipitates for Al6061. Diamond cutting experiments were conducted to machine Al6061 samples under different aging conditions. The experimental results show that, the protruding on the chip surface is mainly Mg_(2)Si and the scratches on the machined surface mostly come from the iron-containing phase(α-, β-AlFeSi).Moreover, the generated Mg_(2)Si and α-, β-AlFeSi affect the surface integrity and the diamond turned surface roughness. Especially, the achieved surface roughness in SPDT is consistent with the variation of the number of AlFeSi and Mg_(2)Si with the medium size(more than 1 μm and less than 2 μm) in Al6061.

关键词： Al6061 precipitates aging treatment diamond cutting surface roughness

Improving fatigue properties of normal direction ultrasonic vibration assisted face grinding Inconel 718 by regulating machined surface integrity

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International Journal of Extreme manufacturing 2024年第3期6卷 458-475页

作者： Nianwei Xu Renke Kang Bi Zhang Yuan Zhang Chenxu Wang Yan Bao Zhigang Dong State Key Laboratory of High-Performance precision manufacturing Dalian University of TechnologyDalian 116024People’s Republic of China department of Mechanical and Energy engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China

Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),and microhardness)after machining ***-direction ultrasonic vibration-assisted face grinding(ND-UVAFG)has advantages in improving the machinability of Inconel 718,but there is a competitive relationship between higher compressiveσ_(res)and higher surface roughness R_(a)in affecting fatigue *** lack of a quantitative relationship between multiple SI indexes and fatigue strength makes theindeterminacy of a regulatory strategy for improving fatigue *** this work,a model of fatigue strength(σ_f)_(sur)considering multiple SI indexes was ***,high-cycle fatigue tests were carried out on Inconel 718 samples with different SI characteristics,and the influence of ND-UVAFG process parameters on SI was *** on SI indexes data,the(σ_f)_(sur)distribution in the grinding surface layer for ND-UVAFG Inconel 718 samples was determined using the developed model,and then the fatigue crack initiation(FCI)sites were *** predicted FCI sites corresponded well with the experimental results,therebyverifying this model.A strategy for improving the fatigue life was proposed in this work,which was to transfer the fatigue source from the machined surface to the bulk material by controlling the SI ***,a critical condition of SI indexes that FCI sites appeared on the surface or in bulk material was given by fitting the predicted *** to the critical condition,an SI field where FCI sites appeared in the bulk material could be *** this field,thefatigue life of Inconel 718 samples could be improved by approximately 140%.

关键词： surface integrity fatigue strength Inconel 718 ultrasonic assisted grinding

Oxygen vacancy boosting Fenton reaction in bone scaffold towards fighting bacterial infection

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International Journal of Extreme manufacturing 2024年第1期6卷 296-311页

作者： Cijun Shuai Xiaoxin Shi Feng Yang Haifeng Tian Pei Feng State Key Laboratory of precision manufacturing for Extreme Service Performance College of Mechanical and Electrical EngineeringCentral South UniversityChangsha 410083People’s Republic of China Institute of Additive manufacturing Jiangxi University of Science and TechnologyNanchang 330013People’s Republic of China College of Mechanical engineering Xinjiang UniversityUrumqi 830017People’s Republic of China

Bacterial infection is a major issue after artificial bone transplantation due to the absence of antibacterial function of bone scaffold,which seriously causes the transplant failure and even amputation in severe *** this study,oxygen vacancy(OV)defects Fe-doped Ti O2(OV-FeTiO2)nanoparticles were synthesized by nano TiO2and Fe3O4via high-energy ball milling,which was then incorporated into polycaprolactone/polyglycolic acid(PCLGA)biodegradable polymer matrix to construct composite bone scaffold with good antibacterial activities by selective laser *** results indicated that OV defects were introduced into the core/shell-structured OV-FeTiO2nanoparticles through multiple welding and breaking during the high-energy ball milling,which facilitated the adsorption of hydrogen peroxide(H2O2)in the bacterial infection microenvironment at the bone transplant *** accumulated H2O2could amplify the Fenton reaction efficiency to induce more hydroxyl radicals(·OH),thereby resulting in more bacterial deaths through·OH-mediated oxidative *** antibacterial strategy had more effective broad-spectrum antibacterial properties against Gram-negative Escherichia coli(***)and Gram-positive Staphylococcus aureus(***).In addition,the PCLGA/OV-FeTiO2scaffold possessed mechanical properties that match those of human cancellous bone and good biocompatibility including cell attachment,proliferation and osteogenic differentiation.

关键词： bacterial infection bone scaffold selective laser sintering Fenton reaction antibacterial properties