The Structure Of Advanced Bulge Instrument And Magnetomechanical Behaviors Of Electromagnetic Materials Under Multi-coupling Loading

Novel electromagnetic materials which have important application prospects and defensesignificance attract global scholar’s attention. Especially they have heterogeneous, complicatedforce-electromagnetic coupled physical and mechanical behaviors and multilayer interfacecoupling characteristics at micro scales, which lead to new challenges and difficulties of currentexperimental characterization techniques and instruments. Other new test characterizationmethods and apparatus are desired to be developed. In this thesis，a new test methods andinstruments which can characterization of the magnetomechanical behaviors of electromagneticmaterials under multi-coupling loading are developed. The main contents in this thesis are listed asfollows,Firstly, a set of novel multi-function bulge test platform which have force-electromagneticcoupling loading was designed and build based on the traditional bulge test device. Majorimprovements include the closed-loop control method was adopted to control the hydraulicloading and a variety of hydraulic load was implemented. Laser displacement sensor was used fornon-contact surface displacement measurement whose accuracy was up to50nm. In addition, themagnetic field loading and calibration system, SMOKE system, S-T circuit system was designedand assembled to implement multi-coupling coupling loading and multi-quantity real-time testing.Secondly, layered electromagnetic thin film PZT/CFO was prepared by sol-gel method, at thesame time, in view of the existing bubbling test specimen preparation which is difficult to apply inlayered electromagnetic thin film, a improved bulge sample preparation methods of layered filmwas explored. In this method single crystals silicon sheet was dealt with wet oxidation process andmachining process, and then blind holes was etched by chemical wet etching, In the end, layeredelectromagnetic film material which have free-standing windows were obtained. In addition, thePZT/Ni composite electromagnetic materials were prepared by the bonding method and chemicalplating respectively.Thirdly, alloys FeCoV film, soft magnetic material Ni film and electromagnetic material PZT/Ni was used for magnetomechanical behaviors test under multi field coupling loadingenvironment by the self-developed bulge platform. The characteristics curves were measured,including the stress-strain curve, hysteresis loop, hysteresis loops at different force fields andelectric field hysteresis loops. The domain theory was used to explain the experimentalphenomena by analysis of experimental results. In general, in this thesis we put forward a set of new characterization technique and testsystem and force-electromagnetic coupling real time test functions by combining matureelectromagnetic test with traditional bulge method which will provide a strong experimentalplatform and research methods to study multi-field coupling behaviors of electromagneticintelligent materials and verify theoretical results of force-electromagnetic coupling field theory.