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Examines the surface relief accompanying martensite and bainite in a copper-zinc-aluminum alloy using atomic force microscopy (AFM). Comparison between the transformation mechanism of bainite and martensite; Information on the surface relief effect; Principles of AFM; Description of the three clusters of relief.

The purpose of this paper is to use the principle of hydraulic amplification and design a piezoelectric drive-based hydraulically amplified flexible Braille contact device with good performance output. In this paper, the structure and working principle of the Braille contact device are described, and the theoretical analysis and parametric design of the hydraulic amplification unit are carried out. The influence relationship between the displacement amplification and diameter and height of the reservoir are obtained by using MATLAB simulation analysis, whereas the output displacement of the piezoelectric vibrator and the flexible film under different driving voltages is measured by using a laser micrometer. Subsequently, the experiments are consistent with the theoretical analysis, and the correctness of the theoretical analysis is verified. Finally, experimental tests of the system are implemented. The results suggest that the displacement amplification ratio is 4.16, and the contact displacement formed by the flexible film is 0.226 mm. Thus, the requirements of the touch sensitivity standard for the blind are satisfied when the reservoir diameter is 20 mm and the reservoir height is 3 mm. The filling water is 7.5 ml, and the resonance frequency is 317.5 Hz. This study proves that constructing a Braille bump device in this way is feasible as well as effective. [ABSTRACT FROM AUTHOR]

To solve the problem of the small deformation of piezoelectric vibrators and improve the overall performance of piezoelectric micro-pumps, a flexible-diaphragm piezoelectric micropump is designed based on hydraulic amplification. The micropump uses a piezoelectric vibrator to provide its driving force, and fluid is delivered by driving the liquid to amplify the displacement of the piezoelectric vibrator. First, the working principle of the piezoelectric micropump is analyzed, and then theoretical analysis and displacement output tests of the hydraulic amplifier unit are carried out. The test results are consistent with those of the theoretical analysis, and the amplification factor of the hydraulic amplifier unit is 3.29. Finally, prototypes are produced and an experimental platform is built for testing. The results indicate that the best-performing piezoelectric micropump has a self-priming height of 1200 mm, an output pressure of 22.16 kPa, and an output flow of 23.18 ml/min. Compared with an ordinary piezoelectric pump, the overall performance of the piezoelectric micropump is greatly improved. [ABSTRACT FROM AUTHOR]