| In the friction process,tribo-magnetization phenomenon of ferromagnetic materials is generated;meanwhile,the spontaneous magnetic field of friction surface is affected by friction heat.In this dissertation,the effect of friction heat on the magnetization of ferromagnetic materials is studied,which is significance to expand relevant theoretical knowledge.The dissertation mainly includes the following aspects:(1)By improving the rotary friction and wear test device existing in laboratory to form a system which can real-time online monitor the changes of near surface temperature,friction coefficient and surface magnetic field of friction pairs in sliding friction process.It provides a test mean for the work to carry out research which the effect of temperature rise caused by friction on the surface magnetic field.(2)In order to investigate friction heat effect on surface magnetic field,reasonable test scheme is formulated,mainly by changing the static load and sliding speed to improve the surface temperature rise.(3)Friction and wear tests of ferromagnetic materials under different working conditions are completed.The experiment results show that the near surface temperature rise with the increase of PV value,meanwhile the surface magnetic field increases firstly and then decreases;when the near surface temperature increases to 150?,the surface magnetic field declines,and the longer the temperature is maintained at 150? above,the more surface magnetic field decreases.(4)The causes of different change trends of magnetic field under magnetization induced by friction and demagnetization caused by friction heat are discussed,influence mechanism of friction heat on surface magnetic field is analyzed. |
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