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Abstract Creating a piezoelectric or pyroelectric material from a ferroelectric material requires aligning its ferroelectric domains to achieve a remanent polarization. This complex process involves nucleating/growing domain structures and inducing a macroscopic, non-centrosymmetric symmetry under an applied electric field. For many years, this process has not received significant attention. Typically, DC fields are applied at elevated temperatures to align the domain states, balancing the depolarization and screening fields in a metastable state that is still near equilibrium. In contrast, the pulse poling (PP) strategy uses field pulses much faster than the time it takes for depolarization and bulk screening processes to occur. This instability allows the PP of relaxor ferroelectric (RFE) crystals and textured ceramics to induce a new far-from-equilibrium (FFE) state, which has enhanced properties compared to conventional DC poling. RFE crystals are of interest because it is known that poling them in specific directions creates engineered domain structures that provide giant piezoelectric properties with low hysteretic losses. By applying PP to RFE crystals in the < 001 > direction, significant changes in the electromechanical properties within the FFE state were observed, which opens new high-performance opportunities for these materials in transducer applications. This review outlines the property enhancements with PP and their origins while modeling the properties with a phenomenological thermodynamic approach. The properties are discussed with respect to transducer applications and benchmarked to other traditional poling strategies. Mn: PMN-PIN-PT, Mn: PMN-PZT, and Sm: PMN-PIN-PT are primarily used as model systems to demonstrate enhanced electromechanical performance with PP over other conventional poling strategies. Given the new concepts discussed in this paper, there is also a future research section at the end of the paper to drive the innovation beyond this initial work. Graphical abstract 

There has been much interest in recent years in improving Direct Current Poling (DCP) for piezoelectric materials. Some of the more promising substitutes include Alternating Current Poling (ACP), Water Quench Poling (WQP), and ACP with Field Cooling (ACP-FC). This paper summarizes the merits of these poling strategies and compares them to pulse poling. The results show that pulse poling outpaces both DCP and ACP in terms of the magnitude of piezoelectric response across a range of materials. Hard and soft piezoelectric samples in both single crystal and textured form were poled using all these techniques. For the single crystal samples (with compositions of Mn: Pb(In1/2Nb1/2)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3 (PIN–PMN–PT) and Sm: PIN–PMN–PT), pulse poling generated the greatest increase in d33 and keff relative to DCP, with both piezoelectrics seeing increases above 65%. In the case of the {001} textured Mn: PMN–PZT–PT material, pulse poling and ACP-FC reduced the loss of the system and improved its mechanical quality factor (Qm) by 20% and 4%, respectively. These phenomena were further investigated via Rayleigh analysis to quantify each poling strategy’s impact on domain wall dynamics. The textured ceramic samples showed lower overall values of α (which is related to the mobility and concentration of domain walls) when compared to the single crystals. It was found that α decreased for the unconventionally poled textured samples relative to DCP, whereas the single crystals’ α values increased. Samples that underwent WQP experienced significant microcracking, limiting possible applications. 

Several research studies have investigated the degradation of BaTiO3-based dielectric capacitor materials, focusing on the impact of composition, defect chemistry, and microstructural design to limit the electromigration of oxygen vacancies under electric fields at finite temperatures. Electromigration can be a dominant mechanism that controls failure rates in the individual multilayer ceramic capacitor (MLCC) components in testing the reliability of failures with highly accelerated lifetime testing (HALT) to determine the mean time to failure of MLCCs surface mounted onto printed circuit boards (PCBs). Conventional assumptions often consider these failures as independent, with no interaction between components on the PCB. However, this study employs a Physics of Failure (PoF) approach to closely examine transient degradation and its impact on MLCC reliability, emphasizing thermal crosstalk and its influence on dependent and independent failure rates. Finite element analysis thermal modeling and infrared thermography were used to assess the impact of circuit layout and component spacing on heat dissipation and thermal crosstalk under various electrical stress conditions. The study distinguishes between dependent and independent failures under a HALT, quantified through a β′ factor reflecting common cause failures due to thermal crosstalk. Through a series of experimental and statistical analyses, the β′ factor is evaluated with respect to temperature, voltage, and component spacing. These insights highlight the importance of understanding the nature of the data in reliability testing of MLCCs and optimizing the layout design of high-density circuits to mitigate dependent failures, improving overall reliability and informing better design and packaging strategies. 

Base metal electrode (BME) multilayer ceramic capacitors (MLCCs) are widely used in aerospace, medical, military, and communication applications, emphasizing the need for high reliability. The ongoing advancements in BaTiO3-based MLCC technology have facilitated further miniaturization and improved capacitive volumetric density for both low and high voltage devices. However, concerns persist regarding infant mortality failures and long-term reliability under higher fields and temperatures. To address these concerns, a comprehensive understanding of the mechanisms underlying insulation resistance degradation is crucial. Furthermore, there is a need to develop effective screening procedures during MLCC production and improve the accuracy of mean time to failure (MTTF) predictions. This article reviews our findings on the effect of the burn-in test, a common quality control process, on the dynamics of oxygen vacancies within BME MLCCs. These findings reveal the burn-in test has a negative impact on the lifetime and reliability of BME MLCCS. Moreover, the limitations of existing lifetime prediction models for BME MLCCs are discussed, emphasizing the need for improved MTTF predictions by employing a physics-based machine learning model to overcome the existing models’ limitations. The article also discusses the new physical-based machine learning model that has been developed. While data limitations remain a challenge, the physics-based machine learning approach offers promising results for MTTF prediction in MLCCs, contributing to improved lifetime predictions. Furthermore, the article acknowledges the limitations of relying solely on MTTF to predict MLCCs’ lifetime and emphasizes the importance of developing comprehensive prediction models that predict the entire distribution of failures.