Wiper tools are revered for their capacity to simultaneously achieve high-quality and high-efficient machining.Nonetheless,the cutting mechanism of wiper tools remains unclear,and the cutting force prediction model of...Wiper tools are revered for their capacity to simultaneously achieve high-quality and high-efficient machining.Nonetheless,the cutting mechanism of wiper tools remains unclear,and the cutting force prediction model of wiper tools has not been reported,leading to severe wear of the bottom wiper edge and unstable cutting in machining processes.In this study,the cutting mechanism of wiper tools is systematically analyzed,and the mechanistic cutting force model considering the wiper edge cutting effect was established.The cutting force coefficients were calibrated by the cutting force separation method,which can quickly calibrate the cutting force coefficients for the flank cutting region dominated by the shear effect,the bottom cutting region dominated by the shear effect,and the bottom wiper region dominated by plough effect.Compared with measured cutting forces,the maximum average absolute errors in the predicted forces are 9.2%,7.6%,and 9.3%in the x,y,and z directions,respectively.Furthermore,the feed rate and the length of the wiper edge were primary determinants of the bottom-edge cutting forces.This study provides theoretical guidance and technical support for the wear mechanism and design of wiper tools.展开更多
High-mass fraction silicon aluminium composite(Si/Al composite) has unique properties of high specific strength, low thermal expansion coefficient, excellent wear resistance and weldability. It has attracted many appl...High-mass fraction silicon aluminium composite(Si/Al composite) has unique properties of high specific strength, low thermal expansion coefficient, excellent wear resistance and weldability. It has attracted many applications in terms of radar communication, aerospace and automobile industry. However, rapid tool wear resulted from high cutting force and hard abrasion, and damaged machined surfaces are the main problem in machining Si/Al composite. This work aims to reveal the mechanisms of milling-induced damages of 70wt% Si/Al composites. A cutting force analytical model considering the characteristics of both the primary silicon particles and the cutting-edge radius was established. Milling experiments were conducted to verify the validity of the model. The results show that the analytical model exhibits a good consistency with the experimental results, and the error is about 10%. The cutting-edge radius has significant effects on the cutting force, surface roughness and damage formation. With the increase in the cutting-edge radius, both the cutting force and the surface roughness decrease firstly and then increase. When the cutting-edge radius is 27 μm, the surface roughness(Sa) reaches the minimum of 2.3 μm.Milling-induced surface damages mainly contain cracks, pits, scratches, matrix coating and burrs.The damage formation is dominated by the failure mode of primary silicon particles, which includes compressive breakage, intragranular fracture, particle pull-out, and interface debonding. In addition, the high ductility of aluminium matrix leads to matrix coating. This work provides guidance for tool selection and damage inhibition in high-efficiency and high-precision machining of high mass fraction Si/Al composites.展开更多
The thermally activated effect can produce a vital influence on the mechanical property and cutting force of metal materials in the machining process.An insight can be gained into the action criteria of the thermally ...The thermally activated effect can produce a vital influence on the mechanical property and cutting force of metal materials in the machining process.An insight can be gained into the action criteria of the thermally activated effect on the cutting force,which provides a solid basis of the research of material performance and machinability.In this study,a cutting force model of selective laser melted(SLMed)Ti6Al4V alloy is proposed by introducing the modified constitutive model with thermally activated effects and the analytical model of the deformation zone into the cutting force model.The anisotropic properties of SLMed Ti6Al4V alloy under different scanning strategies(0°,67.5°,and 90°)are explored by combining with the cutting force model,constitutive model and analytical model of deformation zone(primary deformation and tool-chip contact area).The action of thermally activated effects on the cutting force,primary deformation and tool-chip contact zone is also researched in detail.Milling experiments and predictions of SLMed Ti6Al4V alloy under different scanning strategies have been implemented to reveal the effectiveness of this new model.The comparison results indicate that the proposed milling force model can effectively predict milling force and reflect well on the anisotropy of SLMed Ti6Al4V alloy.In addition,this proposed force model can well analyze the action mechanism of the thermally activated effect on the milling force of SLMed Ti6Al4V alloy,which is significantly essential for the machining mechanism research in terms of a microscopic perspective.展开更多
Virtual manufacturing is fast becoming an affordable technology with wide-ranging applications in modern manufacturing. Its advantages over existing technology are primarily that users can visualize, feel involvement ...Virtual manufacturing is fast becoming an affordable technology with wide-ranging applications in modern manufacturing. Its advantages over existing technology are primarily that users can visualize, feel involvement and interact with virtual representations of real world activities in real time. In this paper, a virtual cutting system is built which can simulate turning process, estimate tool wear and cutting force using artificial neural network etc. Using the simulated machining environment in virtual reality (VR), the user can practise and preview the operations for possible problems that might occur during implementation. This approach enables designers to evaluate and design feasible machining processes in a consistent manner as early as possible during the development process.展开更多
基金Supported by National Key Research and Development Program of China(Grant No.2018YFA0702900)National Natural Science Foundation of China(Grant Nos.52075076,U1908231)。
文摘Wiper tools are revered for their capacity to simultaneously achieve high-quality and high-efficient machining.Nonetheless,the cutting mechanism of wiper tools remains unclear,and the cutting force prediction model of wiper tools has not been reported,leading to severe wear of the bottom wiper edge and unstable cutting in machining processes.In this study,the cutting mechanism of wiper tools is systematically analyzed,and the mechanistic cutting force model considering the wiper edge cutting effect was established.The cutting force coefficients were calibrated by the cutting force separation method,which can quickly calibrate the cutting force coefficients for the flank cutting region dominated by the shear effect,the bottom cutting region dominated by the shear effect,and the bottom wiper region dominated by plough effect.Compared with measured cutting forces,the maximum average absolute errors in the predicted forces are 9.2%,7.6%,and 9.3%in the x,y,and z directions,respectively.Furthermore,the feed rate and the length of the wiper edge were primary determinants of the bottom-edge cutting forces.This study provides theoretical guidance and technical support for the wear mechanism and design of wiper tools.
基金supported by the National Natural Science Foundation of China(No.52075255)the Fundamental Research Funds for the Central Universities(No.NT2021020)。
文摘High-mass fraction silicon aluminium composite(Si/Al composite) has unique properties of high specific strength, low thermal expansion coefficient, excellent wear resistance and weldability. It has attracted many applications in terms of radar communication, aerospace and automobile industry. However, rapid tool wear resulted from high cutting force and hard abrasion, and damaged machined surfaces are the main problem in machining Si/Al composite. This work aims to reveal the mechanisms of milling-induced damages of 70wt% Si/Al composites. A cutting force analytical model considering the characteristics of both the primary silicon particles and the cutting-edge radius was established. Milling experiments were conducted to verify the validity of the model. The results show that the analytical model exhibits a good consistency with the experimental results, and the error is about 10%. The cutting-edge radius has significant effects on the cutting force, surface roughness and damage formation. With the increase in the cutting-edge radius, both the cutting force and the surface roughness decrease firstly and then increase. When the cutting-edge radius is 27 μm, the surface roughness(Sa) reaches the minimum of 2.3 μm.Milling-induced surface damages mainly contain cracks, pits, scratches, matrix coating and burrs.The damage formation is dominated by the failure mode of primary silicon particles, which includes compressive breakage, intragranular fracture, particle pull-out, and interface debonding. In addition, the high ductility of aluminium matrix leads to matrix coating. This work provides guidance for tool selection and damage inhibition in high-efficiency and high-precision machining of high mass fraction Si/Al composites.
基金supported by the Shandong Provincial Natural Science Foundation,China(Grant Nos.ZR2023QE041,ZR2021ME063)the China Postdoctoral Science Foundation(Grant No.2023M731862)the National Natural Science Foundation of China(Grant No.51975112)。
文摘The thermally activated effect can produce a vital influence on the mechanical property and cutting force of metal materials in the machining process.An insight can be gained into the action criteria of the thermally activated effect on the cutting force,which provides a solid basis of the research of material performance and machinability.In this study,a cutting force model of selective laser melted(SLMed)Ti6Al4V alloy is proposed by introducing the modified constitutive model with thermally activated effects and the analytical model of the deformation zone into the cutting force model.The anisotropic properties of SLMed Ti6Al4V alloy under different scanning strategies(0°,67.5°,and 90°)are explored by combining with the cutting force model,constitutive model and analytical model of deformation zone(primary deformation and tool-chip contact area).The action of thermally activated effects on the cutting force,primary deformation and tool-chip contact zone is also researched in detail.Milling experiments and predictions of SLMed Ti6Al4V alloy under different scanning strategies have been implemented to reveal the effectiveness of this new model.The comparison results indicate that the proposed milling force model can effectively predict milling force and reflect well on the anisotropy of SLMed Ti6Al4V alloy.In addition,this proposed force model can well analyze the action mechanism of the thermally activated effect on the milling force of SLMed Ti6Al4V alloy,which is significantly essential for the machining mechanism research in terms of a microscopic perspective.
文摘Virtual manufacturing is fast becoming an affordable technology with wide-ranging applications in modern manufacturing. Its advantages over existing technology are primarily that users can visualize, feel involvement and interact with virtual representations of real world activities in real time. In this paper, a virtual cutting system is built which can simulate turning process, estimate tool wear and cutting force using artificial neural network etc. Using the simulated machining environment in virtual reality (VR), the user can practise and preview the operations for possible problems that might occur during implementation. This approach enables designers to evaluate and design feasible machining processes in a consistent manner as early as possible during the development process.