Neodymium-iron-boron magnet crack fracture prediction method based on particle filtering algorithm

Abstract

The invention discloses a neodymium-iron-boron magnet crack fracture prediction method based on a particle filtering algorithm, and relates to the technical field of metal material fatigue crack fracture prediction, which comprises the steps of introducing a magnetic induction intensity vector of a neodymium-iron-boron magnet into a particle filtering prediction model to serve as a state parameterin the constructed particle filtering model; therefore, the crack propagation information of the neodymium-iron-boron magnet can be continuously monitored. The magnetic signal state vector provided by the invention not only can accurately predict the state change of the magnet when the crack is expanded, but also can monitor the fluctuation change of the magnetic induction intensity signal of themagnet along with the externally applied fatigue load when the magnet is not broken.

Description

technical field [0001] The invention relates to the technical field of metal material fatigue crack fracture prediction, in particular to a particle filter algorithm-based NdFeB magnet crack fracture prediction method. Background technique [0002] As one of the most common forms of damage in workpieces, fatigue cracks will adversely affect the performance of workpieces. As an important metal functional material, NdFeB permanent magnet material has a series of advantages such as high magnetic energy product, high remanence and high coercive force. With its excellent magnetic properties and excellent function conversion, it is widely used in fans, motors and It is widely used in the manufacture of core functional devices in high-tech industries such as the new energy industry. However, the sintering process commonly used today makes the prepared NdFeB magnet prone to uneven density and porosity in the internal structure of the cooling process. At the same time, the local tem...

AI Technical Summary

Problems solved by technology

Due to the particularity of the NdFeB magnet material, which has low fracture toughness, the use of damage mechanics methods cannot describe the formation process of short cracks in the initial stage of NdFeB magnet crack growth, resulting in the prediction results during the crack growth process. less accurate

[0005] Moreover, model-based simulation methods often need to pre-determine some test conditions. For example, the commonly used fatigue crack growth prediction based on the Paris formula, the calculation of the stress field intensity factor amplitude △k parameter is usually through numerical analysis and numerical simulation. Through this Although the prediction results obtained by this method take into account the basic laws of crack growth to a certain extent, they are still based on theoretical or empirical historical experimental data, and the variable parameters are very conservative, which cannot take into account the parameters of NdFeB materials. , the tortuosity change of the actual crack growth path and other uncertain factors

These factors all limit the accuracy and effectiveness of crack propagation fracture prediction

Traditional research methods and model simulations have been unable to accurately predict the evolution process of crack propagation and fracture of NdFeB magnets

Images