A composite fatigue test device for axial and vibration high and low cycles

Abstract

The invention relates to a composite fatigue test device for axial and vibration high and low cycles, comprising a base (2) rigidly connected to the vibration excitation device through a transition plate (1), cantilevers and connecting arms (4) on both sides of the base (2) ) connection, one end of the two connecting rods (5) is installed on the connecting arm (4), and the other end is installed on the beam (6), the bearing (3) on both sides of the beam (6) and the base (2), the connecting arm (4 ) and connecting rods (5) constitute a load frame that cantilever smoothly around the two sides of the base (2). The sample (8) and the axial force applicator (9) are connected in series on the The force applicator (9) is fixed on the base (2). The axial force applicator of the test device of the present invention can axially load the sample. When the excitation equipment is excited at the resonance frequency, the load frame drives the sample to resonate, and the cantilever bending load generated by the resonance is all borne by the sample. In this way, the high cycle vibration fatigue load can be superimposed on the low cycle axial fatigue load.

Description

technical field [0001] The invention belongs to the technical field of mechanical tests, and in particular relates to a composite fatigue test device for axial and vibration high and low cycles. Background technique [0002] Aeroengine blades are subjected to both centrifugal and vibration loads during service. After the engine is started, the high-speed rotation of the blades produces huge centrifugal force, which belongs to low-cycle fatigue loads; the engine blades resonate due to the influence of airflow or structural vibration during operation, which belongs to high-cycle vibration fatigue loads. Therefore, the stress state of the engine blade in actual service is the superposition state of low cycle fatigue load and high cycle vibration fatigue load. According to the "General Specifications for Aeronautical Turbojet and Turbofan Engines" (GJB241A-2010), engine blades and materials need to be subjected to fatigue tests under coordinated loading of axial loads and high-...

AI Technical Summary

Problems solved by technology

[0003] 1. The axial fatigue load is difficult to apply and control accurately;

[0004] 2. The vibration condition of the cantilever is difficult to simulate;

[0005] 3. The frequency of vibration fatigue loading is low, which cannot meet the needs of ultra-high cycle fatigue tests

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