A novel 1-3-2 piezoelectric composite has been developed,which consists of piezoelectric ceramic plate and 1-3 piezoelectric composite.The composite was fabricated by dicing PZT ceramic along mutual perpendicular two ...A novel 1-3-2 piezoelectric composite has been developed,which consists of piezoelectric ceramic plate and 1-3 piezoelectric composite.The composite was fabricated by dicing PZT ceramic along mutual perpendicular two directions and then filling epoxy into grooves.The piezoelectric and electromechanical properties of the novel composite were determined. The results show a coefficient d_ (33) of 405pC/N,a vibration displacement of 113.5pm,an acoustic impendence of 13.3 Mraly, a bandwidth of 12kHz and a thickness electromechanical coupling coefficient of 0.56.展开更多
Effective piezoelectric properties,electromechanical coupling factors(ECF)and figures of merit(FOM)are studied in leadfree 0-3-type composites based on novel ferroelectric 0.965(K_(0.48)Na_(0.52))(Nb_(0.96)Sb_(0.04))O...Effective piezoelectric properties,electromechanical coupling factors(ECF)and figures of merit(FOM)are studied in leadfree 0-3-type composites based on novel ferroelectric 0.965(K_(0.48)Na_(0.52))(Nb_(0.96)Sb_(0.04))O_(3)-0.035Bi_(0.5)Na_(0.5)Zr_(0.15)Hf_(0.75)O_(3) ceramic.Systems of prolate ceramic inclusions are surrounded by a large polymer matrix that can be either monolithic(in the 0-3 composite)or porous(in the 0-3-0 composite).Non-monotonic volume-fraction dependences of the effective piezoelectric coefficients g_(3j)^(*),ECF k_(3j)^(*),squared FOM d_(3j)^(*)g_(3j)^(*)and their modified analogs for stress-driven systems are analysed,and examples of the high longitudinal piezoelectric sensitivity(g33^(*)>100 mV.m/N)are considered.A role of microgeometrical factors,that promote the large effective parameters and anisotropy of properties in the 0-3-type composites,is highlighted.New“aspect ratio-volume fraction”diagrams are first built to describe conditions for high piezoelectric sensitivity,large modified FOM and their anisotropy in the studied composites.These advanced materials can be of value for piezoelectric sensor,energy-harvesting and related applications.展开更多
Composites have been extensively studied for dielectric and related applications.This is a reviewof polymer based 0-3 composites that exhibit a high dielectric constant.These composites areclassified into two types.Di...Composites have been extensively studied for dielectric and related applications.This is a reviewof polymer based 0-3 composites that exhibit a high dielectric constant.These composites areclassified into two types.Dielectric-dielectric composite and conductor-dielectric composite.The physical principles and related models are presented with associated assumptions and ap-proximations.In general,a dielectric-dielectric composite needs a higher concentration of thefillers to reach a high dielectric constant than a conductor-dielectric composite.The high dielectric constant observed in the conductor-dielectric composites is usually associated with ahigh dielectric loss and a low electric breakdown field.The experimental results are summarized toillustrate the principles for,and the achievements in,the development of these composites.The challenges facing the fundamental understanding and the further development of these compo-sites for diferent applications are discussed.展开更多
0-3 dielectric composites with high dielectric constants have received great interest for various technological applications.Great achievements have been made in the development of high performance of 0-3 composites,w...0-3 dielectric composites with high dielectric constants have received great interest for various technological applications.Great achievements have been made in the development of high performance of 0-3 composites,which can be classified into dielectric–dielectric(DDCs)and conductor–dielectric composites(CDCs).However,predicting the dielectric properties of a composite is still a challenging problem of both theoretical and practical importance.Here,the physical aspects of 0-3 dielectric composites are reviewed.The limitation of current understanding and new developments in the physics of dielectric properties for dielectric composites are discussed.It is indicated that the current models cannot explain well the physical aspects for the dielectric properties of 0-3 dielectric composites.For the CDCs,experimental results show that there is a need to find new equations/models to predict the percolative behavior incorporating more parameters to describe the behavior of these materials.For the DDCs,it is indicated that the dielectric loss of each constituent has to be considered,and that it plays a critical role in the determination of the dielectric response of these types of composites.The differences in the loss of the constituents can result in a higher dielectric constant than both of the constituents combined,which breaks the Wiener limits.展开更多
Piezoelectric properties and related figures of merit are studied in novel 1-3-type composites based on ferroelectric domain-engineered lead-free single crystal with the relatively large longitudinal piezoelectric coe...Piezoelectric properties and related figures of merit are studied in novel 1-3-type composites based on ferroelectric domain-engineered lead-free single crystal with the relatively large longitudinal piezoelectric coefficient d_(33).Relationships between the piezoelectric properties and the set of figures of merit are analyzed for the 1-3 and 1-3-0 composites that contain the same single-crystal and polymer components.For a composite characterized by 1-3-0 connectivity,an influence of a porous piezo-passive matrix on the figures of merit and their volume-fraction behavior is considered additionally.A large anisotropy of figures of merit is observed in the 1-3-0 composite with specific porous matrices.A diagram is put forward to show volume-fraction regions of the large anisotropy of figures of merit of the studied 1-3-0 composite.Due to large figures of merit and their considerable anisotropy,the studied lead-free composites can be applied in piezoelectric energy-harvesting systems,sensors,transducers,and so on.展开更多
In the present work,piezoelectric composite films made of Polyaniline(PAni)coated Lead Zirconate Titanate(PZT)particles immersed into polyvinylidene fluoride(PVDF)matrix were characterized by mechanical tests,and the ...In the present work,piezoelectric composite films made of Polyaniline(PAni)coated Lead Zirconate Titanate(PZT)particles immersed into polyvinylidene fluoride(PVDF)matrix were characterized by mechanical tests,and the connectivity of the com-posite sample was determined using dielectric measurements and applying the Poon–Shin model.The composite was considered a binary system with coated PZT particles as one phase and the polymer matrix the other one.To support the result obtained from theoretical analysis,scanning electron microscopy of the composites were done.It was observed a decrease up to 85%on the mechanical resistance when the ceramic volume fraction increases from 0%to 40%.Furthermore,the composite film no longer can be considered with 0–3 connectivity when the ceramic content is 30 vol.%or over.展开更多
基金supported by the Beijing Natural Science Foundation of China(No.KZ200410772016)Academic Innovative Team Program of University in Beijing.
文摘A novel 1-3-2 piezoelectric composite has been developed,which consists of piezoelectric ceramic plate and 1-3 piezoelectric composite.The composite was fabricated by dicing PZT ceramic along mutual perpendicular two directions and then filling epoxy into grooves.The piezoelectric and electromechanical properties of the novel composite were determined. The results show a coefficient d_ (33) of 405pC/N,a vibration displacement of 113.5pm,an acoustic impendence of 13.3 Mraly, a bandwidth of 12kHz and a thickness electromechanical coupling coefficient of 0.56.
文摘Effective piezoelectric properties,electromechanical coupling factors(ECF)and figures of merit(FOM)are studied in leadfree 0-3-type composites based on novel ferroelectric 0.965(K_(0.48)Na_(0.52))(Nb_(0.96)Sb_(0.04))O_(3)-0.035Bi_(0.5)Na_(0.5)Zr_(0.15)Hf_(0.75)O_(3) ceramic.Systems of prolate ceramic inclusions are surrounded by a large polymer matrix that can be either monolithic(in the 0-3 composite)or porous(in the 0-3-0 composite).Non-monotonic volume-fraction dependences of the effective piezoelectric coefficients g_(3j)^(*),ECF k_(3j)^(*),squared FOM d_(3j)^(*)g_(3j)^(*)and their modified analogs for stress-driven systems are analysed,and examples of the high longitudinal piezoelectric sensitivity(g33^(*)>100 mV.m/N)are considered.A role of microgeometrical factors,that promote the large effective parameters and anisotropy of properties in the 0-3-type composites,is highlighted.New“aspect ratio-volume fraction”diagrams are first built to describe conditions for high piezoelectric sensitivity,large modified FOM and their anisotropy in the studied composites.These advanced materials can be of value for piezoelectric sensor,energy-harvesting and related applications.
文摘Composites have been extensively studied for dielectric and related applications.This is a reviewof polymer based 0-3 composites that exhibit a high dielectric constant.These composites areclassified into two types.Dielectric-dielectric composite and conductor-dielectric composite.The physical principles and related models are presented with associated assumptions and ap-proximations.In general,a dielectric-dielectric composite needs a higher concentration of thefillers to reach a high dielectric constant than a conductor-dielectric composite.The high dielectric constant observed in the conductor-dielectric composites is usually associated with ahigh dielectric loss and a low electric breakdown field.The experimental results are summarized toillustrate the principles for,and the achievements in,the development of these composites.The challenges facing the fundamental understanding and the further development of these compo-sites for diferent applications are discussed.
基金supported by an USDA(2014-67022-21694)grant and a NASA grant(Grant#G00007275).
文摘0-3 dielectric composites with high dielectric constants have received great interest for various technological applications.Great achievements have been made in the development of high performance of 0-3 composites,which can be classified into dielectric–dielectric(DDCs)and conductor–dielectric composites(CDCs).However,predicting the dielectric properties of a composite is still a challenging problem of both theoretical and practical importance.Here,the physical aspects of 0-3 dielectric composites are reviewed.The limitation of current understanding and new developments in the physics of dielectric properties for dielectric composites are discussed.It is indicated that the current models cannot explain well the physical aspects for the dielectric properties of 0-3 dielectric composites.For the CDCs,experimental results show that there is a need to find new equations/models to predict the percolative behavior incorporating more parameters to describe the behavior of these materials.For the DDCs,it is indicated that the dielectric loss of each constituent has to be considered,and that it plays a critical role in the determination of the dielectric response of these types of composites.The differences in the loss of the constituents can result in a higher dielectric constant than both of the constituents combined,which breaks the Wiener limits.
基金The authors are grateful to Prof.Dr.I.A.Parinov and Prof.Dr.A.E.Panich(Southern Federal University,Russia),and Prof.Dr.C.R.Bowen(University of Bath,UK)for their interest in the field of modern piezo-active materials and applications.Research was financially supported by Southern Federal University,grant No.VnGr-07/2020-04-IM(Ministry of Science and Higher Education of the Russian Federation).
文摘Piezoelectric properties and related figures of merit are studied in novel 1-3-type composites based on ferroelectric domain-engineered lead-free single crystal with the relatively large longitudinal piezoelectric coefficient d_(33).Relationships between the piezoelectric properties and the set of figures of merit are analyzed for the 1-3 and 1-3-0 composites that contain the same single-crystal and polymer components.For a composite characterized by 1-3-0 connectivity,an influence of a porous piezo-passive matrix on the figures of merit and their volume-fraction behavior is considered additionally.A large anisotropy of figures of merit is observed in the 1-3-0 composite with specific porous matrices.A diagram is put forward to show volume-fraction regions of the large anisotropy of figures of merit of the studied 1-3-0 composite.Due to large figures of merit and their considerable anisotropy,the studied lead-free composites can be applied in piezoelectric energy-harvesting systems,sensors,transducers,and so on.
文摘In the present work,piezoelectric composite films made of Polyaniline(PAni)coated Lead Zirconate Titanate(PZT)particles immersed into polyvinylidene fluoride(PVDF)matrix were characterized by mechanical tests,and the connectivity of the com-posite sample was determined using dielectric measurements and applying the Poon–Shin model.The composite was considered a binary system with coated PZT particles as one phase and the polymer matrix the other one.To support the result obtained from theoretical analysis,scanning electron microscopy of the composites were done.It was observed a decrease up to 85%on the mechanical resistance when the ceramic volume fraction increases from 0%to 40%.Furthermore,the composite film no longer can be considered with 0–3 connectivity when the ceramic content is 30 vol.%or over.
