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The combination of superelastic shape memory alloy fibers and ECC materials can form a new SMA fiber reinforced ECC composite material (SMAF-ECC) with good self-centering performance. In order to study the self-centering performance of the new composite material, 6 groups of pre-notch beam specimens were made for three-point bending cyclic loading tests, and the failure phenomenon, hysteresis curve, self-centering effect and influencing factors of the specimens were analyzed. The research results show that when the SMA fibers are effectively anchored in the ECC matrix, the SMA fibers can exert the superelastic properties to provide the ECC beams with recoverying force, and realize the crack self-closure and deflection self-recovery function for the beams, with the minimum residual crack width and deflection is only 0.9 mm and 1.3 mm respectively. Increasing fiber content can cause a small increase in the self-centering ability of the beams. However, only when the fiber diameter is appropriate, better self-centering effect can be achieved, but the difference caused by fiber diameter in the test was only 5%. SMA Fiber end forms have significant influence on self-centering performance. The knotted end beam can get a more than 70% self-centering ratio, while the straight end beams and bended end beams have no self-centering ability. The research results provide important reference for the research and application of this new self-centering materials and their structures. [ABSTRACT FROM AUTHOR]

The electrical and optical properties of (001)‐ and (110)‐oriented 0.73 Pb(Mg1/3Nb2/3)O3‐0.27PbTiO3 single crystals are systematically investigated at various temperatures, both of which present a series of ferroelectric phase transition processes. Dielectric performance measurements reveal that the ferroelectric phase transition occurs over a temperature range, rather than at one temperature point. By testing the ferroelectric hysteresis P–E curves as well as bipolar and unipolar electric field‐induced strain S–E curves, the values of remnant polarization, coercive field, maximum strain, and converse piezoelectric constant d33* change considerably near the phase transition temperatures. Simultaneously, the 0.73PMN‐0.27PT single crystals with (001)‐ and (110)‐orientations under a low electric field show ultrahigh d33* values of 3540 and 2817 pm/V, respectively, which can be attributed to the electric field‐induced monoclinic and orthorhombic phases, respectively. The series of ferroelectric phase transitions upon heating, that is, from rhombohedral ferroelectric to monoclinic/orthorhombic, followed by from monoclinic/orthorhombic to tetragonal, and finally from tetragonal to cubic paraelectric, are further investigated via polarized light microscopy and Raman spectroscopy. The 0.73PMN‐0.27PT single crystals present a series of ferroelectric phase transition processes, which is confirmed by dielectric performance measurement, polarized light microscopy and Raman spectra contour plot. The electric field induced monoclinic and orthorhombic phase contribute to the ultra‐high d33- in the (001)‐ and (110)‐orientations crystals. [ABSTRACT FROM AUTHOR]

Using the polycrystalline material with a nominal composition of Nd0.01Pb0.985[(Mg1/3Nb2/3)0.70Ti0.30]O3, an Nd-doped PMN–PT single crystal has been grown successfully by a vertical Bridgman process. The perovskite structure and the crystalline phase evolution of the as-grown crystal were confirmed by X-ray diffraction analysis. A series of (001)-oriented crystal wafers, fabricated from different regions of the as-grown crystal boule, were characterized systematically to verify their electrical properties. Compared to the undoped PMN–PT single crystal, the crystal wafers under direct current polarization exhibited an improved piezoelectric coefficient d33 of 1780–2870 pC N−1, along with a lower phase transition temperature T and a lower Curie temperature Tc in the range of 55–63 °C and 95–141 °C, respectively. The coercive field Ec and the remnant polarization Pr for the crystal wafers were measured to be 1.7–2.7 kV cm−1 and 23.9–32.7 μC cm−2, respectively. It was found that the piezoelectric coefficient d33 of the crystal wafer could be even elevated to the range 2200–3650 pC N−1 by applying alternating current polarization. The improved piezoelectricity for the crystal wafer under alternating current polarization may be associated with the increased domain density inside the crystal medium. [ABSTRACT FROM AUTHOR]

An optimal annealing condition (360 °C, 10 min) was found for the FeBSiC Metglas, at which the Metglas transformed into a mix phase structure between amorphous and crystalline. It gives a deformation of single-layer FeBSiC Metglas ribbon increases from 26.9 ppm of the unannealed sample to 34.6 ppm, piezomagnetic coefficient d33,m from 1.9 to 2.6 ppm/Oe, and the loss decreases from 0.18 to 0.07%. After the mix phase Metglas and Mn-doped 0.71Pb(Mg1/3Nb2/3)O3-0.29PbTiO3 (Mn-doped PMN-PT) single crystal were fabricated into a magnetoelectric (ME) laminate composite, it is found that αQ at quasi-static and resonance frequency rises from 2183 to 2640 pC/Oe, and from 120,000 to 165,000 pC/Oe, with the increase amplitude of 21% and 37.5%, respectively. From test of realistic noise, the equivalent noise magnetic field (EMN) @1 Hz of the ME sensor made by mix phase Metglas declines from 20.2 to 15.4 pT/Hz1/2, and EMN@30 Hz from 1.46 to 1.23 pT/Hz1/2. The reinforcement of the piezomagnetic performance is attributed to the generation of mix phase structure. It can enhance ME coupling performance at quasi-static and resonance state, reduce loss, and boost the sensitivity of the ME sensor. [ABSTRACT FROM AUTHOR]

In this work, we establish a magnetoelectric antenna system. The receiver is an in-plane series sensor composed of Mn-PMNT crystal fibers and Metglas. It has excellent magnetic field detection ability, reaching 3.1 pT/Hz1/2 under 1 Hz. We fabricated an asymmetric ME antenna based on PZT-5 H and Metglas at the transmitting end. The transmitter has two resonance peaks at a very low frequency (VLF), and its radiation ability can reach 73 nT at 14 kHz and 6.3 nT at 5.63 kHz. Furthermore, a nonlinear magnetostrictive model is constructed, and the ME effects are discussed through finite element mode. This model indicates that the near-field radiation capability of the device is strongly influenced by the frequency and magnetic bias, with the maximum performance achieved when the ME composite operates at the resonant frequency and the optimal piezomagnetic coefficient. [Display omitted] • The nonlinear near-field acoustic excitation antenna model can predict the resonant frequency of ME composites. • The PZT/Metglas magnetoelectric antenna fabricated in this work has two resonant frequencies in the very low-frequency band. The transmission capacity reaches 73 nT at 14 kHz and 6.3 nT at 5.63 kHz. Under limited external environmental interference, the signal can be recognized at 12.4 m and 5.2 m, respectively. • The receiver is made of Mn-PMNT fiber single crystals and Metglas and has an equivalent noise magnetic field of 3.1 pT/Hz1/2 whose detection sensitivity is better than multi-push-pull (MPP) magnetoelectric sensor (5.3 pT/Hz1/2). [ABSTRACT FROM AUTHOR]

Due to the good dielectric, piezoelectric and ferroelectric properties, the pseudo-ternary ferroelectric single crystals Pb(In 1/2 Nb 1/2)O 3 -Pb(Mg 1/3 Nb 2/3)O 3 -PbTiO 3 (PIN-PMN-PT) have been widely concerned and studied. In this study we found that the dynamic hysteresis loop area with electric field E 0 and frequency f 0 of the 0.16 Pb(In 1/2 Nb 1/2)O 3 -0.62 Pb(Mg 1/3 Nb 2/3)O 3 -0.22PbTiO 3 (0.16PIN-0.62PMN-0.22 PT) single crystals satisfies the relational equation ∝ E 0 βf 0 α. In the ∝ E 0 β relationship, both linear stages are found correlated with the low electric field in the first stage E 0 3E c. The hysteresis loop area with frequency f 0 relationship satisfies the equation ∝ f 0 α with roughly linear trend and the hysteresis loop area decreases with increasing frequency f 0. Such electric field dependent dynamic hysteresis scaling can be observed by polarized light microscopy. Image 1 [ABSTRACT FROM AUTHOR]

The fatigue resistance of pseudo-ternary single crystal 0.22Pb(In 1/2 Nb 1/2)O 3 -0.53Pb(Mg 1/3 Nb 2/3)O 3 -0.25PbTiO 3 (PIMNT) is tested by a "two-step poling process" – alternate current poling (ACP) with different cycles followed by direct current poling (DCP). The remnant polarization of the hysteresis loop decreases significantly and then does not change, and the coercive field raises with increasing polarization cycles. However, the two-step poling process contributes to the optimization and stability of fatigue resistance. Before 700 cycles, the piezoelectric constant d 33 of the crystal is obviously promoted compared with the conventional DCP sample of d 33 = 2200 pC/N, which increases by 40.9%–3100 pC/N, while the average thickness mode electromechanical coupling coefficient K t remains at 0.518. With the increase in number of polarization cycles, the d 33 and K t are larger and more stable than for the ACP only sample. This improvement is due to nanoscale denser and smaller domains induced by the two-step poling process. • Two-step poling process gives single-crystal PIMNT good performance, stability and fatigue resistance. • Before 700 cycles, the process increases d 33 from 2200 to 3100 pC/N and average K t remains at 0.518 • The d 33 and K t of PIMNT after this process are larger and more stable than single AC aging. • The process reduces domain size to nanoscale and domains become denser and smaller. [ABSTRACT FROM AUTHOR]

The temperature stability and temperature stability range of barium titanate-based pulse energy-storage ceramics were modified by Bi 2 O 3 tailoring in (Ba 0.98- x Li 0.02 Bi x) (Mg 0·04 Ti 0.96)O 3 (x = 0, 0.025, 0.05, 0.075, 0.1) and (Ba 1.03-1.5 x Li 0.02 Bi x) (Mg 0·04 Ti 0.96)O 3 (x = 0.125, 0.15, 0.2, 0.25) ceramics. Excellent pulse energy-storage performances of ceramic films are achieved via the new dual priority strategy of establishing cationic vacancies and forming a liquid phase. The dielectric constant plateau appears due to the cubic phase and space charges. Outstanding temperature stability, frequency stability and antifatigue performance are obtained in the ceramics, and their variations are all less than 15%. The comprehensive energy-storage properties with dual priority parameters of energy-storage density and efficiency of 3.13 J/cm3 and 91.71%, accompanied by an excellent pulse discharge energy density of 2.48 J/cm3, current density of 1313.23 A/cm2 and power density of 195.26 MW/cm3 are gained at x = 0.1. The perfect pulse energy-storage performances as well as ultrahigh stability are correlated with synergistic effects of multiphase coexistence, cubic phase, liquid-phase sintering, grain size, ceramic resistance, space charges and polar nanoregions. The comprehensive parameters indicate that the (Ba 0·88 Li 0·02 Bi 0.1) (Mg 0·04 Ti 0.96)O 3 ceramics have potential application in high precision fields. [ABSTRACT FROM AUTHOR]

Magnetoelectric (ME) sensors have been proven to have great performance on weak magnetic field detection with high sensitivity, low noise, broad bandwidth and low power consumption. In this work, a self-designed ME detection system consisting of a high-performance triaxial ME sensor was used for magnetic anomaly detection (MAD). As the core sensing element of the ME sensor, the laminated ME composites were made of Metglas laminates and Mn-doped PMN-PT single crystal fibers with in-plane series connection. The noise equivalent magnetic induction (NEB) of the ME sensors were below 6.28pT/Hz1/2 @ 1 Hz, and the limit detection of magnetic field is about 5 × 10−10 T, representing great performance to detect weak magnetic field. An experiment of detecting a real ship was conducted to test the performance of the triaxial ME detection system. To analyze the magnetic anomaly signal induced by the ship, a 3D finite element model (FEM) about the magnetic field distribution of the moving ship is developed. The estimated signals of the scalar total magnetic field and the motion parameters of the ship simulated by the proposed FEM match well with the experimental data, which proves the reliability of the model. The error analysis of the simulation was also discussed in detail. The experimental investigation reveals a promising application of ME sensor in MAD, while the proposed finite element model can be further modified to meet the analysis requirements on the detection of the magnetic anomaly induced by ferromagnetic targets with large dimension. • The noise equivalent magnetic induction of ME sensors are below 6.28pT/Hz1/2 @ 1 Hz. • Outdoor MAD experiment of a ship was conducted by a triaxial ME detection system. • FEM of magnetic anomaly for large dimension ferromagnetic targets was developed. • Motion parameters of the ship can be estimated by the propose FEM [ABSTRACT FROM AUTHOR]

With the popularity of electric vehicles, the ever-increasing demand for high-capacity batteries highlights the need for monitoring the health status of batteries. In this article, we proposed a magnetic imaging technique (MIT) to investigate the health status of power batteries nondestructively. This technique is based on a magnetic sensor array, which consists of a 16-channel high-performance magnetoelectric sensor, and the noise equivalent magnetic induction (NEB) of each channel reaches 3–5 pT/Hz1/2@10 Hz. The distribution of the magnetic field is imaged by scanning the magnetic field variation of different positions on the surface. Therefore, the areas of magnetic anomalies are identified by distinguishing different magnetic field abnormal results. and it may be possible to classify the battery failure, so as to put forward suggestions on the use of the battery. This magnetic imaging method expands the application field of this high-performance magnetoelectric sensor and contributes to the battery's safety monitoring. Meanwhile, it may also act as an important role in other nondestructive testing fields. [ABSTRACT FROM AUTHOR]