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纤维随机分布CFRP高速铣削比能模型与表面质量优化

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机械工程学报 2024年第1期60卷 65-74页

作者：宋阳曹华军张金刘磊张琼之重庆大学机械与运载工程学院重庆400044 重庆大学机械传动国家重点实验室重庆400044

碳纤维增强复合材料(Carbon fiber reinforced plastics, CFRP)具有高比模量和比强度、耐腐蚀性和良好的刚度等优良特性,逐渐被广泛应用于航空航天、汽车、国防军工及生物医疗等高端装备领域。然而,CFRP材料的非均质性及各向异性致使其... 详细信息

碳纤维增强复合材料(Carbon fiber reinforced plastics, CFRP)具有高比模量和比强度、耐腐蚀性和良好的刚度等优良特性,逐渐被广泛应用于航空航天、汽车、国防军工及生物医疗等高端装备领域。然而,CFRP材料的非均质性及各向异性致使其加工表面形貌非常复杂且极易产生加工缺陷,严重制约了CFRP结构件的使用寿命、服役性能及安全可靠性。鉴于高速切削技术有利于提高加工效率和控制表面质量,而切削比能是加工表面质量的重要指标,因此,首先通过引入碳纤维分布、切削效应及边缘效应,阐明切削比能的来源及分布,建立CFRP高速铣削的切削比能预测模型,该比能预测模型精度91.19%。然后,采用三维均方根面粗糙度和三维分形维数对表面质量进行定量表征,根据比能分量与表面质量之间的相关性分析,定义了面向表面质量的比能综合评价指标SCEsq和SCEds,提出基于比能的表面质量优化方法。最后,基于非线性回归分析,分析了铣削参数对SCEsq和SCEds的影响,验证了高速切削有利于减少CFRP加工缺陷。

关键词： CF/PEEK 高速铣削切削比能表面质量纤维分布

大振幅超声振动辅助高速干切装置设计开发与性能测试

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重庆大学学报 2024年第9期47卷 14-29页

作者：黄雪峰曹华军张金宋阳康信禛重庆大学机械与运载工程学院重庆400044

超声换能器是超声振动辅助切削装置的核心部件,为研制适用于高速干切的大振幅超声振动辅助切削装置,需先设计研制超声换能器。基于考虑刀具的二级放大超声换能器设计方法,遵循“变幅杆-超声换能器”一体式设计理念,结合ANSYS有限元软件... 详细信息

超声换能器是超声振动辅助切削装置的核心部件,为研制适用于高速干切的大振幅超声振动辅助切削装置,需先设计研制超声换能器。基于考虑刀具的二级放大超声换能器设计方法,遵循“变幅杆-超声换能器”一体式设计理念,结合ANSYS有限元软件的模态分析和谐响应分析结果,设计并研制了二级放大超声换能器。根据研制的二级放大超声换能器特性,系统设计并研制与其相匹配的超声波发生器、止转环、输电系统和刀柄壳结构。对二级放大超声换能器进行了阻抗分析和振幅测量等性能测试。对所设计研制的大振幅超声振动辅助高速干切装置开展实验测试分析,探究了其对难加工材料30CrMnSiNi2A加工表面质量的改善程度。结果表明:二级放大超声换能器纵向振动仿真结果与理论设计一致,二级放大超声换能器输出振幅稳定,在50%输出功率下纵振振幅为15.4μm,最大可达25.1μm,且输出振幅与功率百分比呈正相关,性能良好;所研制的大振幅超声振动辅助切削装置可大幅降低进给方向切削力和表面粗糙度,显著提高难加工材料加工表面质量,适用于难加工材料高速干切。

关键词：二级放大超声换能器有限元仿真分析大振幅超声振动辅助切削装置振幅超声振动辅助高速干切

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不等螺旋角立铣刀瞬时铣削力模型与验证

机械工程学报 2024年第15期60卷 393-406页

作者：施壮李长河刘德伟张彦彬秦爱国曹华军陈云青岛理工大学机械与汽车工程学院青岛266520 青岛卡沃斯智能制造有限公司青岛266100 重庆大学机械与运载工程学院重庆400044 成都工具研究所有限公司成都610500

随着航空航天轻量化趋势的迫切需求,铣削是框架类弱刚度零部件不可或缺的加工方法,然而铣削过程瞬时力变化导致薄壁结构件等弱刚度工件的颤振产生加工变形是其技术瓶颈。而立铣刀不等分齿间角和螺旋角已被证实是抑制颤振的有效方法。但... 详细信息

随着航空航天轻量化趋势的迫切需求,铣削是框架类弱刚度零部件不可或缺的加工方法,然而铣削过程瞬时力变化导致薄壁结构件等弱刚度工件的颤振产生加工变形是其技术瓶颈。而立铣刀不等分齿间角和螺旋角已被证实是抑制颤振的有效方法。但切削力变化是诱发工艺系统颤振的本源,不等螺旋角立铣刀铣削弱刚度结构件力学行为尚未完善。基于此,建立了不等螺旋角立铣刀瞬时铣削力数学模型。首先,分析了不等螺旋角周向平面化下角度位置关系,研究了切削刃之间的轴向时变特性对任意轴向位置瞬时切削厚度的影响关系,建立了不等分齿间角微元体的力模型并轴向积分后得到单刃瞬时切削力模型。其次,分析了不等螺旋角切削刃在切削域中的参与情况,并提出了多刃同时切削时多窗口函数叠加的铣削力线性预测方法。进一步的,采用了线性回归后的斜切变换方法进行系数标定,得到了基于铣削斜变化下的系数预测方法。最后,开展了传统立铣刀与不等螺旋角立铣刀干式铣削Ti-6Al-4V验证性实验。结果表明,线性回归方法下的传统立铣刀数值解与测量值在进给方向Fy平均误差为1.17%,切削表面法向Fx平均误差为2.09%。铣削斜切变换方法下不等螺旋角立铣刀得到的Fy平均误差为0.13%,相比于线性回归方法预测精度提高了6.36%。不等螺旋角导致切削刃之间具备的轴向时变特性,是导致了力信号周期性改变,抑制颤振的根本原因。

关键词：铣削钛合金弱刚度铣削力螺旋角齿间角

An energy consumption prediction approach of die casting machines driven by product parameters

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Frontiers of Mechanical Engineering 2021年第4期16卷 868-886页

作者： Erheng CHEN Hongcheng LI huajun cao Xuanhao WEN State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China School of Advanced Manufacturing Engineering Chongqing University of Posts and TelecommunicationChongqing 400065China

Die casting machines,which are the core equipment of the machinery manufacturing industry,consume great amounts of *** energy consumption prediction of die casting machines can support energy consumption quota,process parameter energy-saving optimization,energy-saving design,and energy efficiency evaluation;thus,it is of great significance for Industry 4.0 and green ***,due to the uncertainty and complexity of the energy consumption in die casting machines,there is still a lack of an approach for energy consumption prediction that can provide support for process parameter optimization and product design taking energy efficiency into *** fill this gap,this paper proposes an energy consumption prediction approach for die casting machines driven by product ***,the system boundary of energy consumption prediction is defined,and subsequently,based on the energy consumption characteristics analysis,a theoretical energy consumption model is ***,a systematic energy consumption prediction approach for die casting machines,involving product,die,equipment,and process parameters,is ***,the feasibility and reliability of the proposed energy consumption prediction approach are verified with the help of three die casting machines and six types of *** results show that the prediction accuracy of production time and energy consumption reached 91.64%and 85.55%,***,the proposed approach can be used for the energy consumption prediction of different die casting machines with different products.

关键词： die casting machine energy consumption prediction product parameters

Model of Surface Texture for Honed Gear Considering Motion Path and Geometrical Shape of Abrasive Particle

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 311-325页

作者： Yuhu Liu Xiaohui Huang huajun cao Jiacheng Wang Huapan Xiao College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China

Gear power-honing is mainly applied to finish small and medium-sized automotive gears,especially in new energy *** distinctive curved surface texture greatly improves the noise emission and service life of honed *** surface texture for honed gear considering the motion path and geometrical shape of abrasive particles has not been *** this paper,the kinematics of the gear honing process is analyzed,and the machining marks produced by the abrasive particles of honing wheel scratching abrasive particles against the workpiece gear are *** tooth surface roughness is modeled considering abrasive particle shapes and material plastic *** results in a mathematical model that characterizes the structure of the tooth surface and the orientation of the machining *** were used to verify the model,with a maximum relative error of less than 10%when abrasive particles are *** on this model,the effects of process parameters on the speeds of discrete points on the tooth flank,orientations of machining marks and roughness are *** results show that the shaft angle between the workpiece gear and the honing wheel and the speed of the honing wheel is the main process parameters affecting the surface *** research proposes a surface texture model for honed gear,which can provide a theoretical basis for optimizing process parameters for gear power-honing.

关键词： Hardened gear Gear power-honing Surface texture Roughness

Assessment of fatigue life of remanufactured impeller based on FEA

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Frontiers of Mechanical Engineering 2016年第3期11卷 219-226页

作者： Lei XU huajun cao Hailong LIU Yubo ZHANG The State Key Laboratory of Mechanical Transmission Chongqing University Chongqing 400030 China National Key Laboratory for Remanufacturing Academy of Armored Forces Engineering Beijing 100072 China

Predicting the fatigue life of remanufactured centrifugal compressor impellers is a critical problem. In this paper, the S-N curve data were obtained by combining experimentation and theory deduction. The load spectrum was compiled by the rain-flow counting method based on the comprehensive consideration of the centrifugal force, residual stress, and aerodynamic loads in the repair region. A fatigue life simulation model was built, and fatigue life was analyzed based on the fatigue cumulative damage rule. Although incapable of providing a high-precision predic- tion, the simulation results were useful for the analysis of fatigue life impact factors and fatigue fracture areas. Results showed that the load amplitude greatly affected fatigue life, the impeller was protected from running at over-speed, and the predicted fatigue life was satisfied within the next service cycle safely at the rated speed.

关键词： remanufactured impeller fatigue life impeller failures finite element analysis (FEA)

Mathematical Model and Geometrical Model of Double Pitch ZN-type Worm Gear Set Based on Generation Mechanism

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Chinese Journal of Mechanical Engineering 2015年第3期28卷 549-555页

作者： SHU Linsen cao huajun LI Xianchong ZHANG Chenglong LI Yuxia State Key Laboratory of Mechanical Transmission Chongqing University

The current researches on the tooth surface mathematical equations and the theory of gearing mainly pay attention to the ordinary type worm gear set（e.g., ZN, ZA, or ZK）. The research of forming mechanism and three-dimensional modeling method for the double pitch worm gear set is not enough. So there are some difficulties in mathematical model deducing and geometry modeling of double pitch ZN-type worm gear set based on generation mechanism. In order to establish the mathematical model and the precise geometric model of double pitch ZN-type worm gear set, the structural characteristics and generation mechanism of the double pitch ZN-type worm gear set are investigated. Mathematical model of the ZN-type worm gear set is derived based on its generation mechanism and the theory of gearing. According to the mathematical model of the worm gear set which has been developed, a geometry modeling method of the double pitch ZN-type worm and worm gear is presented. Furthermore, a geometrical precision calculate method is proposed to evaluate the geometrical quality of the double pitch worm gear set. As a result, the maximum error is less than 6′10–4 mm in magnitude, thus the model of the double pitch ZN-type worm gear set is available to meet the requirements of finite element analysis and engineering application. The derived mathematical model and the proposed geometrical modeling method are helpful to guiding the design, manufacture and contact analysis of the worm gear set.

关键词： double pitch ZN-type worm gear set generation mechanism mathematical model geometrical model

Coupling evaluation for material removal and thermal control on precision milling machine tools

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Frontiers of Mechanical Engineering 2022年第1期17卷 70-82页

作者： Kexu LAI huajun cao Hongcheng LI Benjie LI Disheng HUANG State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China School of Advanced Manufacturing Engineering Chongqing University of Posts and TelecommunicationChongqing 400065China College of Mechatronic Engineering Southwest Petroleum UniversityChengdu 610500China

Machine tools are one of the most representative machining systems in *** energy consumption of machine tools has been a research hotspot and frontier for green low-carbon ***,previous research merely regarded the material removal(MR)energy as useful energy consumption and ignored the useful energy consumed by thermal control(TC)for maintaining internal thermal stability and machining *** pursuit of energy-efficient,high-precision machining,more attention should be paid to the energy consumption of TC and the coupling relationship between MR and ***,the cutting energy efficiency model considering the coupling relationship is established based on the law of conservation of *** index of energy consumption ratio of TC is proposed to characterize its effect on total energy ***,the heat characteristics are analyzed,which can be adopted to represent machining *** study indicates that TC is the main energy-consuming process of the precision milling machine tool,which overwhelms the energy consumption of *** forced cooling mode of TC results in a 7%reduction in cutting energy *** analysis shows that heat dissipation positively contributes 54.1%to machining accuracy,whereas heat generation negatively contributes 45.9%.This paper reveals the coupling effect of MR and TC on energy efficiency and machining *** can provide a foundation for energyefficient,high-precision machining of machine tools.

关键词： machine tools cutting energy efficiency thermal stability machining accuracy coupling evaluation

Nondestructive acquisition of the micro-mechanical properties of high-speed-dry milled micro-thin walled structures based on surface traits

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Chinese Journal of Aeronautics 2021年第5期34卷 438-451页

作者： Da QU Wei ZHENG Bo WANG Bo WU huajun cao Hao YI The State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China College of Mechanical Engineering Chongqing UniversityChongqing 400044China Aerospace Research Institute of Materials&Processing Technology Beijing 100076China Centre for Precision Engineering Harbin Institute of TechnologyHarbin 150001China

Requirements for the service performance of aeronautic microelectronic components are increasingly ***,sever issues,that the acquisition of the service performance such as micro-mechanical properties is destructive,limit the subsequent application of the tested *** this issue,this paper proposes a nondestructive acquisition method of the micro-mechanical properties of the accelerometer micro-components,based on analyzing surface *** select qualified components without damage,we firstly developed a quasi-static microtensile tester and then established a combination prediction model of mechanical properties based on micro-milled surface *** model works due to the thin-walled structure,which makes the machined surface traits have significant influences on the mechanical properties such as Young’s modulus,yield strength,tensile strength,and elongation at *** roughness,surface structure,and surface anisotropy are extracted to comprehensively present surface traits from different *** improving the practicability of the model,the principal component analysis(PCA)is adopted to reduce high-dimensional traits explanatory variable space into two dimensions,and regression analysis models are comparative established in predicting the mechanical *** analysis and error analysis are carried out to show the prediction *** maximum prediction error is about 10.62%,but the significance levels in the t-test of the predicted Young’s modulus and yield strength are not ***,kernel support vector regression(SVR)is imported to improve the prediction ability of the combination prediction *** residuals analysis result shows that SVR is effective in enhancing the prediction ability of this model.

关键词： Dimension reduction High-speed dry micro-milling Mechanical property Nondestructive acquisition SVR