Method for testing vibration fatigue performance of metal in axial resonance state

A technology of vibration fatigue and testing method, which is applied in the field of resonance fatigue, can solve the problems of insufficient high-frequency output and high cost of ordinary fatigue test time, and achieve the effect of shortening the test cycle

CN110542525AActive Publication Date: 2019-12-06上海航空材料结构检测股份有限公司
15 Cites 12 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Publication Date
2019-12-06

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention provides a method for testing the vibration fatigue performance of metal in an axial resonance state. The method comprises steps: selecting a test piece, pasting a strain gauge, and measuring a response acceleration-strain / stress relationship of the test piece in a resonance state; in combination with the planned stress level, calculating the response acceleration of the test piece during formal test; carrying out the modal test on the test piece to obtain an inherent frequency point and a response amplitude ratio of axial vibration; setting the excitation frequency according tothe inherent frequency point, and calculating an excitation acceleration according to the response amplitude ratio measured by the test; finely adjusting a real-time excitation acceleration value in the test so that target response acceleration change is + / -2%; setting a resonance search and resonance residence program to keep the test piece in a resonance state in the test process, and stopping the test when the response acceleration of the test piece is suddenly reduced or the test piece is broken; and obtaining the cycles of the vibration system when the test is stopped. The method is advantaged in that the axial fatigue test is carried out on a metal material in a vibration mode, and the test period can be greatly shortened.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention belongs to the technical field of resonance fatigue, and in particular relates to a method for testing the vibration fatigue performance of a metal in an axial resonance state. Background technique

[0002] During ground operations and air flight, some parts of the aircraft are always in the environment of aerodynamic load and noise. Due to the excitation of noise and aerodynamic load, random vibration stress is generated in these parts. Some structures, such as rudder surface, flat tail, vertical tail, ventral fins and external pylons, etc., will also generate vibration stress due to the effect of turbulence. The fatigue phenomenon caused by the action of this vibration stress is vibration fatigue.

[0003] There are many problems involved in solving structural dynamic fatigue, and dynamic fatigue analysis is one of the important problems. In order to perform a dynamic fatigue analysis on a structure, a dynamic fatigue SN curve is requ...

Examples

Embodiment Construction

[0042] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

[0043] A method for testing the vibration fatigue performance of a metal in an axial resonance state provided by the present invention can be found in Figure 5 , including the following steps:

[0044] S1: Design the shape and size of the axial sample in combination with the vibration environment where the material is located and the physical performance parameters of the material. Specifically, after the sample is processed, the shape and size of the notch c...