Sub-ultrasonic high-frequency fatigue testing machine

Abstract

The invention discloses a sub-ultrasonic high-frequency fatigue testing machine. An energy converter used as a driving force source, the energy converter, a tested sample and a driven amplitude transformer form a resonance system, and a prearranged static loading mechanism provides static load for a test piece. The energy converter can be a full-wavelength energy converter or a half-wavelength energy converter. The energy converter converts an electric signal into mechanical vibration under the driving of an external alternating voltage, so the whole system is in a resonance state, and the tested sample has resonance vibration and a stress, thereby the fatigue detection can be realized. The energy converter can be a piezoelectric energy converter or a giant magnetostrictive energy converter. The sub-ultrasonic high-frequency fatigue testing machine allows the sub-ultrasonic high-frequency fatigue tests of the test piece under different stress ratios to be carried out according to the system prearrangement state; compared with traditional high-frequency fatigue testing machines, the sub-ultrasonic high-frequency fatigue testing machine has the advantages of simple structure, small volume, test period shortening, high efficiency and energy saving; and compared with present ultrasonic fatigue testing machines, the sub-ultrasonic high-frequency fatigue testing machine has the advantage of reduction of the frequency effect and the dimension effect to the material fatigue performances.

Description

technical field [0001] The invention belongs to the field of fatigue detection and testing, and more specifically relates to a fatigue testing device at a sub-ultrasonic frequency (5kHz-15kHz). Background technique [0002] High-frequency fatigue testing machine is widely used in testing the fatigue properties of metal and non-metallic components such as tension and compression, torsion, bending, pitting corrosion, etc. , electronics, aviation, aerospace, metallurgy and other fields have a wide range of applications. Existing high-frequency fatigue testing machines are all driven by electromagnetic drive or electro-hydraulic servo drive, and the general working frequency is not more than 500Hz. However, the high cycle fatigue cycle of the material is between 10 5 ~10 7 Between, the cycle of ultra-high cycle fatigue is as high as 10 8 above. Such a large time and economic cost limit the current high-cycle and ultra-high-cycle fatigue tests and research. The frequency of...

AI Technical Summary

Problems solved by technology

Such a large time and economic cost limit the current high-cycle and ultra-high-cycle fatigue tests and research

The frequency of the existing ultrasonic fatigue testing machine is about 20kHz, which will bring about the frequency effect of the fatigue performance of the material. At the same time, the working frequency of the ultrasonic fatigue testing machine of 20kHz limits the size of the tested piece, which will bring about the size effect of the fatigue performance.

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