The remarkable ability of titanium alloys to preserve their superior physical and chemical characteristics when subjected to extreme conditions significantly enhances their importance in the aerospace,military,and med...The remarkable ability of titanium alloys to preserve their superior physical and chemical characteristics when subjected to extreme conditions significantly enhances their importance in the aerospace,military,and medical sectors.However,conventional machining of titanium alloys leads to elevated tool wear,development of surface defects,and reduced machining efficiency due to their low heat conductivity,and chemical affinity.These issues can be somewhat counteracted by integrating ultrasonic vibration in the conventional machining of titanium alloys and also enhance sustainability.This review article offers a holistic evaluation of the influence of ultrasonic vibration-assisted milling and turning on cutting forces,temperature,tool wear,and surface integrity,encompassing surface morphology,surface roughness,surface residual stress,surface hardness,and surface tribological properties during titanium alloys machining.Furthermore,it investigates the sustainability aspect that has not been previously examined.Studies on the performance of ultrasonic-assisted cutting revealed several advantages,including decreased cutting forces and cutting temperature,improved tool life,and a better-machined surface during machining.Consequently,the sustainability factor is improved due to minimized energy consumption and residual waste.In conclusion,the key challenges and future prospects in the ultrasonic-assisted cutting of titanium alloys are also discussed.This review article provides beneficial knowledge for manufactur-ers and researchers regarding ultrasonic vibration-assisted cutting of titanium alloy and will play an important role in achieving sustainability in the industry.展开更多
This paper studies the vibration responses of porous functionally graded(FG)thin plates with four various types of porous distribution based on the physical neutral plane by employing the peridynamic differential oper...This paper studies the vibration responses of porous functionally graded(FG)thin plates with four various types of porous distribution based on the physical neutral plane by employing the peridynamic differential operator(PDDO).It is assumed that density and elastic modulus continuously vary along the transverse direction following the power law distribution for porous FG plates.The governing differential equation of free vibration for a porous rectangular FG plate and its associated boundary conditions are expressed by a Lévy-type solution based on nonlinear von Karman plate theory.Dimensionless frequencies and mode shapes are obtained after solving the characteristic equations established by PDDO.The results of the current method are validated through comparison with existing literature.The effects of geometric parameters,material properties,elastic foundation,porosity distribution,and boundary conditions on the frequency are investigated and discussed in detail.The highest fundamental dimensionless frequency occurs under SCSC boundary conditions,while the lowest is under SFSF boundary conditions.The porous FG plate with the fourth pore type,featuring high density of porosity at the top and low at the bottom,exhibits the highest fundamental frequency under SSSS,SFSF,and SCSC boundary conditions.The dimensionless frequency increases with an increase in the elastic foundation stiffness coefficient.展开更多
This study determined the optimal concentration of titanium diboride (TiB2) particles for the development of in situ titanium– titanium boride (Ti–TiB) metal matrix composites (MMCs) prepared by a conventional powde...This study determined the optimal concentration of titanium diboride (TiB2) particles for the development of in situ titanium– titanium boride (Ti–TiB) metal matrix composites (MMCs) prepared by a conventional powder metallurgy route to be used for industrial applications. The effect of concentration of TiB2 particles was studied by reinforcing TiB2 powder in different mass fractions (2wt%, 5wt%, 10wt%, and 20wt%) into pure Ti powder during the fabrication process. The MMCs were sintered at high temperatures under vacuum. The transmission electron microscopy (TEM) results revealed the formation of needle-shaped TiB whiskers, indicating that in situ reaction occurred during vacuum sintering of the powder compacts. All the composite samples had a high sintered density, and the hardness of the composites increased with an increase in the mass fraction of reinforcement. Mechanical and tribological properties such as flexural strength, impact, and wear properties were determined and found to be dependent on the mass fraction of the reinforcement. However, the mechanism for the in situ reaction needs further investigation by high-energy in situ X-ray diffraction techniques.展开更多
Aero-engines,the core of air travel,rely on advanced high strength-toughness alloys(THSAs)such as titanium alloys,nickel-based superalloys,intermetallics,and ultra-high strength steel.The precision of cutting techniqu...Aero-engines,the core of air travel,rely on advanced high strength-toughness alloys(THSAs)such as titanium alloys,nickel-based superalloys,intermetallics,and ultra-high strength steel.The precision of cutting techniques is crucial for the manufacture of key components,including blades,discs,shafts,and gears.However,machining THSAs pose significant challenges,including high cutting forces and temperatures,which lead to rapid tool wear,reduced efficiency,and compromised surface integrity.This review thoroughly explores the current landscape and future directions of cutting techniques for THSAs in aero-engines.It examines the principles,mechanisms,and benefits of energy-assisted cutting technologies like laser-assisted machining and cryogenic cooling.The review assesses various tool preparation methods,their effects on tool performance,and strategies for precise shape and surface integrity control.It also outlines intelligent monitoring technologies for machining process status,covering aspects such as tool wear,surface roughness,and chatter,contributing to intelligent manufacturing.Additionally,it highlights emerging trends and potential future developments,including multi-energy assisted cutting mechanisms,advanced cutting tools,and collaborative control of structure shape and surface integrity,alongside intelligent monitoring software and hardware.This review serves as a reference for achieving efficient and high-quality manufacturing of THSAs in aero-engines.展开更多
Detrimental physical and mechanical properties are common pro-blems for composites when their flame retardancy is improved through filler additions.An increased interest of the synergistic nanoparticle addition to imp...Detrimental physical and mechanical properties are common pro-blems for composites when their flame retardancy is improved through filler additions.An increased interest of the synergistic nanoparticle addition to improve the flame retardancy of natural fiber composites is the aim of this work.The paper investigates the synergistic effect of two different nanoparticles(halloysite nano-tubes(HNTs)and montmorillonite(MMT)nanoclay)on the flame and mechanical properties in an intumescent ammonium poly-phosphate(APP)-based polypropylene(PP)/kenaf composite sys-tem.First,the nature of nanoparticle dispersion in PP through X-ray diffraction(XRD)and transmission electron microscopy(TEM)reveals that under twin screw compounding process,the partial exfoliation and intercalation have taken place within the nano-composites.An increase in the decomposition temperature was observed under thermogravimetric analysis(TGA),with the pre-sence of HNT.However,MMT tends to lower the maximum decomposition temperature under inert atmosphere.The flamm-ability analysis in an intumescent flame retardant(IFR)system shows that the suitable amount of high aspect ratio nanoparticles with their exfoliation characteristics effectively helps to reduce the sustained combustion.Even though,improved stiffness properties can be observed with the presence of increased filler content,particle agglomeration tends to reduce the mechanical strengths of these composites due to low compatibilization and crack propagation.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.92160301,92060203,52175415 and 52205475)the Science Center for Gas Turbine Project(No.P2023-B-IV-003-001)+1 种基金the Natural Science Foundation of Jiangsu Province(No.BK20210295)the Huaqiao University Engineering Research Center of Brittle Materials Machining(MOE,2023IME-001)。
文摘The remarkable ability of titanium alloys to preserve their superior physical and chemical characteristics when subjected to extreme conditions significantly enhances their importance in the aerospace,military,and medical sectors.However,conventional machining of titanium alloys leads to elevated tool wear,development of surface defects,and reduced machining efficiency due to their low heat conductivity,and chemical affinity.These issues can be somewhat counteracted by integrating ultrasonic vibration in the conventional machining of titanium alloys and also enhance sustainability.This review article offers a holistic evaluation of the influence of ultrasonic vibration-assisted milling and turning on cutting forces,temperature,tool wear,and surface integrity,encompassing surface morphology,surface roughness,surface residual stress,surface hardness,and surface tribological properties during titanium alloys machining.Furthermore,it investigates the sustainability aspect that has not been previously examined.Studies on the performance of ultrasonic-assisted cutting revealed several advantages,including decreased cutting forces and cutting temperature,improved tool life,and a better-machined surface during machining.Consequently,the sustainability factor is improved due to minimized energy consumption and residual waste.In conclusion,the key challenges and future prospects in the ultrasonic-assisted cutting of titanium alloys are also discussed.This review article provides beneficial knowledge for manufactur-ers and researchers regarding ultrasonic vibration-assisted cutting of titanium alloy and will play an important role in achieving sustainability in the industry.
基金supported by the Research Start-Up Fund for Introducing Talents from Anhui Polytechnic University(S022023032)the Program for Synergy Innovation in the Anhui Higher Education Institutions of China(GXXT-2021-044 and GXXT-2022-082)+2 种基金the Scientific Research Foundation of Education Department of Anhui Province,China(2022AH040361)the National Natural Science Foundation of China(12172114)the Natural Science Funds for Distinguished Young Scholar of Anhui Province of China(2208085J25).
文摘This paper studies the vibration responses of porous functionally graded(FG)thin plates with four various types of porous distribution based on the physical neutral plane by employing the peridynamic differential operator(PDDO).It is assumed that density and elastic modulus continuously vary along the transverse direction following the power law distribution for porous FG plates.The governing differential equation of free vibration for a porous rectangular FG plate and its associated boundary conditions are expressed by a Lévy-type solution based on nonlinear von Karman plate theory.Dimensionless frequencies and mode shapes are obtained after solving the characteristic equations established by PDDO.The results of the current method are validated through comparison with existing literature.The effects of geometric parameters,material properties,elastic foundation,porosity distribution,and boundary conditions on the frequency are investigated and discussed in detail.The highest fundamental dimensionless frequency occurs under SCSC boundary conditions,while the lowest is under SFSF boundary conditions.The porous FG plate with the fourth pore type,featuring high density of porosity at the top and low at the bottom,exhibits the highest fundamental frequency under SSSS,SFSF,and SCSC boundary conditions.The dimensionless frequency increases with an increase in the elastic foundation stiffness coefficient.
基金partially supported by the Titanium Technologies New Zealand (TiTeNZ) Programme funded by the Ministry of Business Innovation and Employment (MBIE), New Zealand
文摘This study determined the optimal concentration of titanium diboride (TiB2) particles for the development of in situ titanium– titanium boride (Ti–TiB) metal matrix composites (MMCs) prepared by a conventional powder metallurgy route to be used for industrial applications. The effect of concentration of TiB2 particles was studied by reinforcing TiB2 powder in different mass fractions (2wt%, 5wt%, 10wt%, and 20wt%) into pure Ti powder during the fabrication process. The MMCs were sintered at high temperatures under vacuum. The transmission electron microscopy (TEM) results revealed the formation of needle-shaped TiB whiskers, indicating that in situ reaction occurred during vacuum sintering of the powder compacts. All the composite samples had a high sintered density, and the hardness of the composites increased with an increase in the mass fraction of reinforcement. Mechanical and tribological properties such as flexural strength, impact, and wear properties were determined and found to be dependent on the mass fraction of the reinforcement. However, the mechanism for the in situ reaction needs further investigation by high-energy in situ X-ray diffraction techniques.
基金National Natural Science Foundation of China(Nos.92160301,92060203,52175415,and 52205475)Science Center for Gas Turbine Project(No.P2023-B-IV-003-001)+1 种基金Natural Science Foundation of Jiangsu Province(No.BK20210295)Fundamental Research Funds for the Central Universities(Nos.NS2023028 and NG2024015)。
文摘Aero-engines,the core of air travel,rely on advanced high strength-toughness alloys(THSAs)such as titanium alloys,nickel-based superalloys,intermetallics,and ultra-high strength steel.The precision of cutting techniques is crucial for the manufacture of key components,including blades,discs,shafts,and gears.However,machining THSAs pose significant challenges,including high cutting forces and temperatures,which lead to rapid tool wear,reduced efficiency,and compromised surface integrity.This review thoroughly explores the current landscape and future directions of cutting techniques for THSAs in aero-engines.It examines the principles,mechanisms,and benefits of energy-assisted cutting technologies like laser-assisted machining and cryogenic cooling.The review assesses various tool preparation methods,their effects on tool performance,and strategies for precise shape and surface integrity control.It also outlines intelligent monitoring technologies for machining process status,covering aspects such as tool wear,surface roughness,and chatter,contributing to intelligent manufacturing.Additionally,it highlights emerging trends and potential future developments,including multi-energy assisted cutting mechanisms,advanced cutting tools,and collaborative control of structure shape and surface integrity,alongside intelligent monitoring software and hardware.This review serves as a reference for achieving efficient and high-quality manufacturing of THSAs in aero-engines.
基金This work was supported by the Ministry of Business,Innovation and Employment[(UOAX 1004)].
文摘Detrimental physical and mechanical properties are common pro-blems for composites when their flame retardancy is improved through filler additions.An increased interest of the synergistic nanoparticle addition to improve the flame retardancy of natural fiber composites is the aim of this work.The paper investigates the synergistic effect of two different nanoparticles(halloysite nano-tubes(HNTs)and montmorillonite(MMT)nanoclay)on the flame and mechanical properties in an intumescent ammonium poly-phosphate(APP)-based polypropylene(PP)/kenaf composite sys-tem.First,the nature of nanoparticle dispersion in PP through X-ray diffraction(XRD)and transmission electron microscopy(TEM)reveals that under twin screw compounding process,the partial exfoliation and intercalation have taken place within the nano-composites.An increase in the decomposition temperature was observed under thermogravimetric analysis(TGA),with the pre-sence of HNT.However,MMT tends to lower the maximum decomposition temperature under inert atmosphere.The flamm-ability analysis in an intumescent flame retardant(IFR)system shows that the suitable amount of high aspect ratio nanoparticles with their exfoliation characteristics effectively helps to reduce the sustained combustion.Even though,improved stiffness properties can be observed with the presence of increased filler content,particle agglomeration tends to reduce the mechanical strengths of these composites due to low compatibilization and crack propagation.
