High-temperature electrochemistry is widely used in many fields. However, real-time observations and an in-depth understanding of the inside evolution of this system from an experimental perspective remain limited because of harsh reaction conditions and multiphysics fields. Here, we tackled this challenge with a high-temperature electrolysis facility developed in-house. This facility permits in situ x-ray computer microtomography (μ-CT) for nondestructive and quantitative three-dimensional (3D) imaging. In an electrorefining system, the μ-CT probed the dynamic evolution of 3D morphology and components of electrodes (4D). Subsequently, this 4D process was visually presented via reconstructed images. The results monitor the efficiency of the process, explore the dynamic mechanisms, and even offer real-time optimization. This 4D analysis platform is notable for in-depth combinations of traditional electrochemistry with digital twin technologies owing to its multiscale visualization and high efficiency of data extraction.

Conventionally, to produce a linear motion, one motor’s stator is employed to drive one runner moving forward or backward. So far, there is almost no report of one electromechanical motor or piezoelectric ultrasonic motor that can directly generate two symmetrical linear motions, while this function is desired for precise scissoring and grasping in the minimally invasive surgery field. Herein, we report a brand-new symmetric-actuating linear piezoceramic ultrasonic motor capable of generating symmetrical linear motions of two outputs directly without additional mechanical transmission mechanisms. The key component of the motor is an (2 × 3) arrayed piezoceramic bar stator operating in the coupled resonant mode of the first longitudinal ( L 1 ) and third bending ( B 3 ) modes, leading to symmetric elliptical vibration trajectories at its two ends. A pair of microsurgical scissors is used as the end-effector, demonstrating a very promising future for high-precision microsurgical operations. The sliders of the prototype show the following features: (a) symmetrical, fast relative moving velocity (~1 m/s) outward or inward simultaneously; (b) high step resolution (40 nm); and (c) high power density (405.4 mW/cm 3 ) and high efficiency (22.1%) that are double those of typical piezoceramic ultrasonic motors, indicating the full capacity of symmetric-actuating linear piezoceramic ultrasonic motor working in symmetric operation principle. This work also has enlightening significance for future symmetric-actuating device designs.

In this work, we report a cofired-12-layer ceramic based standing-wave linear piezoelectric ultrasonic micromotor (SW-LPUM) with a high-load-density using LiCO3 doped 0.05Pb(Mn1/3Sb2/3)O3-0.47PbZrO3-0.48PbTiO3 (PMnS-PZT) material. The proposed SW-LPUM features a miniaturized structure (12.45 × 5.3 × 3.5 mm3) and excellent comprehensive actuation performances, such as fast response time (0.05 ms), high resolution (50 nm), and broad adjustable velocity range (from 0.01 to 123.7 mm s−1). Specifically, its high load density (11.0 mN mm−3) under a single-phase voltage drive is higher than that of most reported LPUMs. The elaborate multilayer structure based on hard-type PMnS-PZT ceramic enables the micromotor to continuously operate without obvious temperature rise, showing its practical value for high-precision positioning.

An elevated-temperature in situ microtomography apparatus that can measure internal damage parameters under tensile loads at high temperatures up to 1000 °C is developed using a laboratory x-ray source. The maximum resolution of the apparatus can reach 3 µm by a reasonable design. A high-temperature environment is accomplished by means of a heating chamber based on a radiation technique using four halogen lamps with ellipsoidal reflectors. To obtain high resolution, the chamber is much smaller in the direction of the x-ray beam than in the other two directions. Two thin aluminum windows are chosen as the chamber walls perpendicular to and intersecting the x-ray beam. A material testing machine equipped with two synchronous rotating motors is specially designed for mechanical loading and 360° rotation of the specimen, and customized grips are developed to conduct tensile tests. A microfocus x-ray source and a high-resolution detector are used to produce and detect X rays, and the distances among the x-ray source, specimen, and high-resolution detector can be adjusted to obtain different resolutions. To show the main functions and usability of the apparatus, carbon-fiber-reinforced silicon-carbide matrix specimens are subjected to in situ x-ray microtomography tensile tests at 800 °C and 1000 °C, and the crack propagation behavior under thermomechanical coupling loads is studied.

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