The domain structure of ferroelectric ceramics can be altered by the process of electrical poling. This paper develops quantitative approaches for reflection geometry and spherical harmonic texture analysis, both of which describe these changes at angles parallel to and tilted from the poling axis. The x-ray-diffraction approach uses the relative intensity ratio of ferroelectric poles in poled and unpoled lead zirconate titanate to calculate a domain switching fraction (η) or a multiple of a random distribution, which are shown to be linearly related. An x-ray area detector diffractometer was used for these measurements, although the technique applies to any x-ray reflection geometry. The neutron-diffraction approach employs a Rietveld refinement with a spherical harmonic texture model. Both approaches calculate similar domain textures for two poling fields and the small differences between the approaches can be attributed to surface domain texture. This paper shows that the March–Dollase pole distribution function can inadequately describe domain textures.

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This paper introduces saturated domain switching textures of three different ferroelastic ceramic crystal systems. The accompanying extrinsic domain switching strain is calculated exclusively using a volume-weighted integral of a single pole figure. In ceramics which are also ferroelectric, the electromechanical response is defined by the domain switching textures, strains, and strain asymmetry, which are found to be functions of the number and directions of possible ferroelastic structural distortions.

Purpose Increasing use of 3D printing techniques to manufacture consumer products and open-source designs raises the question of “What is the mechanical reliability of 3D printed parts?” Therefore, the purpose of this paper is to investigate the impacts of build orientation on the mechanical reliability of acrylonitrile butadiene styrene (ABS) produced using 3D printing. Design/methodology/approach Tensile tests on ABS specimens were performed with and without a hole in the center, which were produced by fused deposition modeling (FDM). Seven sets of approximately 30 specimens were printed in XY, XZ and C+45 orientations to obtain reliable fracture statistics. Weibull analysis was performed to quantify the variation in the tensile strength. Findings The Weibull analysis showed that the reliability of FDM produced ABS can be as low as advanced ceramics. Weibull moduli of specimens without a hole were between 26 and 69, and specimens with a hole had Weibull moduli between 30 and 41. P-type deviations from the Weibull statistics were observed. The XZ orientation resulted in the highest average fracture strength for specimens with and without a hole, and C+45 orientation resulted in the lowest strength. Practical implications As the Weibull distribution relates the applied stress to probability of failure, the Weibull analysis provides a practical design criterion to achieve specific reliability levels for additively manufactured parts. Originality/value This study, for the first time, provides Weibull statistics for FDM-produced ABS parts, which can be used to predict mechanical reliability.

Piezoelectricity is manifested in ferroelectric ceramics by inducing a preferred volume fraction of one ferroelectric domain variant orientation at the expense of degenerate orientations. The piezoelectric effect is therefore largely controlled by the effectiveness of the electrical poling in producing a bias in ferroelectric (180°) and ferroelastic (non‐180°) domain orientations. Further enhancement of the piezoelectric effect in bulk ceramics can be accomplished by inducing preferred orientation through grain‐orientation processes such as hot forging or tape casting that precede the electrical‐poling process. Coupled crystal orientation and domain orientation processing yields ceramics with an even greater piezoelectric response. In this paper, preferred orientations of domains and grains in polycrystalline piezoelectric ceramics generated through both domain‐ and grain‐orientation processing are characterized through pole figures and orientation distribution functions obtained using data from a variety of diffraction techniques. The processing methods used to produce these materials and the methods used to evaluate preferred orientation and texture are described and discussed in the context of prior research. Different sample and crystal symmetries are explored across a range of commercial and laboratory‐prepared materials. Some of the variables presented in this work include the effects of in situ thermal depoling and the detailed processing parameters used in tape casting of materials with preferred crystallite orientations. Preferred orientation is also correlated with anisotropic properties, demonstrating a clear influence of both grain and domain orientations on piezoelectricity.