基于微磁测量与磁化分布重构的轴承磨损评估

文章提出了超导量子干涉器件（SQUID）对轴承润滑油中铁屑产生的微磁场进行监测，进而评估轴承磨损程度的方法，并进行了可行性验证试验。为基于检测信号确定润滑油中的铁屑含量，提出了对油液管道内部磁化分部进行重构的方法，通过数值模拟研究了其有效性。结果表明，SQUID可以检测铁粉颗粒所产生的微小磁场，且信号幅度与含量有明确对应关系；反演程序可有效重构管道内部的铁磁成分分布磁化，即使信号中有20％白噪声，重构结果也在可信范围。

Measurement and Reconstruction of Tiny Magnetic Field for Bearing Wearing Evaluation

The feasibility to evaluate wearing status of the bearing system by using the Superconducting Quantum Interference Device(SQUID) magnetometer was studied in this paper.To predict the status of the ferromagnetic particles in bearing oil from the magnetic field signals measured by SQUID,a scheme was also proposed and validated to reconstruct the distribution of magnetization in oil pipe from the measured signals.The experimental results verified that the SQUID was very efficient for the measurement of micro-magnetic field due to magnetic particles,and its signal amplitudes had clear correlation with’the amount of the particles.In addition,the numerical results revealed that the proposed inverse analysis scheme and the developed code were applicable for the reconstruction of the distribution of magnetic particles.For magnetic signals even with 20%noise,the magnetization information inside a pipe could be properly reconstructed.