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Magnetization of ferromagnetic materials in geomagnetic field by mechanical strain - Prinicple of metal magnetic memory testing and diagnostic technique

Wei-Chang Zhong
Nanjing Gas Turbine Research Institute, 47 Northern Central Road,
Nanjiing, 210037, People's Republic of China


1.Magnetization by machining and magnetization through operation

2.The magnetization by strain under a directional stress

3.The magnetization by unsymmetrical elastic-plastic strain under an alternative stress

4.The process of spontaneous magnetization

Fig 3: The spontaneous magnetization process of ferromagnetic materials. Fig 4: The diagram of magneto-elasticity phenomenon development
DB - residual induction change
Ds- cyclic load change
H e - externald magnetic field




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