Research On Composite Manufacture Based On Ferromagnetic Amorphous Microwires And Its Sensitivity Feature

As the traditional functional fiber material,the ferromagnetic microwires is highly concerned when it had been manufactured for the first time.Many magentic field sensor based on ferromagnetic microwires have been widely used in engneering area.Ferromagnetic microwires exhibit outstanding mechnical property with high tensile modulus and strength,excellent flexiblity make it can not be broken even under large bending deformation.Besides the outstanding mechanical property,ferromagnetic microwires have various sensing function,such as GMI(Giant Magneto-Impedance),GSI(Giant Stress Impedance)and Barkhausen effect which can be utilized as transducing mechanism for different sensors.Althrough ferromagentic microwires have many outstanding sensing property,its application mainly focus on magnetic and electric property and neglect the excellent mechanical property which may constrain the application area of the ferromagnetic microwires.As fiber shape functional material,ferromagnetic microwires can be integrate with composite material by winding and laying technology to measure material strain,result in functional structure integration.This article adequately utilized fiber shape,excellent mechanical property and sensing performance of the ferromagnetic microwires,design and manufacture meta-material surface to measure CFRP strain,fiber shape strain sensor to measure material strain,gas flow sensor to measure air-flow velocity and artificial hairy skin tactile sensor to measure pressure in robot hand field.Firstly,we design and manufacture ferromagentic mcirowires meta-material surface array on carbon fiber reinforced plastic surface based on Nature Ferro-Magnetic Resonance phenomenon of the Fe-rich amorphous microwires.Through theoretical mathematics,we obtain saturated permeability,gyromagnetic ratio and anisotropic magnetiostatic field effect to carbon fiber reinforced plastic reflection coefficient and reflection frequency.We analyze the Fe-rich amorphous microwires array geometry structure parameter effect to reflection absorption amplitude and optimization design the array density and diameter of the Fe-rich magnetic microwires.To manufacture regular Fe-rich amorphous microwires array,a miniature home-made winding machine is designed and constructed to prepare uniformly controlable density ferromagentic microwires array.Different density ferromagetic microwires array were integated into the surface of the carbon fiber reinforecd plastic to develop meta-material surface.The interfacial shear stress between Fe-rich microwires and epoxy resin have crucial influence to force conditions of the microwires array,so AFM(Atomic Force Microscope)was used to observe surface topography of the microwire and find the smooth surface because of the glass-cover in the microwire surface.The smooth surface means that the mechanical occlusion effect between the epoxy resin and the ferromagnetic microwire is very weak which has been demonstrated by the Interfacial Sheay Stress experiment.The glass-cover on the ferromagnetic microwire surface is rich in Si O2 and the silane coupling agent may enhance the adhesion force between the epoxy resin and the microwire.After surface treatment,the Interfacial Sheay Stress between the epoxy and the ferromagnetic microwires meets the demands for force sensing application.Finally,meta-material surface based on Fe-rich ferromagnetic microwires and carbon fiber reinforced plastic was tested by the vector network analyzer.The S11 parameter of the meta-material surface responses to the applied stress increase as the theoretical prediction.The experiment result proved that the meta-material surface may be applied in the carbon reinforced plastic strain measurement.Based on Matteucci effect of the Co-rich ferromagnetic microwires,we design and manufacture fiber shape strain sensor based on Co-rich microwires and varnished wires twining on it.Under the alternating current magnetic field generated by varnished wires coils,the induced current would be developed in the Co-rich.The amplitude of the induced current would reduce with the applied tensile force,the reason is that the circumferential domain of the ferromagnetic would orientate along axial direction under the applied tensile force and reduce the vibrating domain around the direction of polarization.The fiber shape strain sensor was fixed on the surface of the composite and the tensile experiment was utilized to test the strain sensor performance.The experiment result shows that the fiber shape strain sensor based on Co-rich ferromagnetic microwires has excellent sensitivity and linearity which means the fiber shape strain sensor can measure material strain during the tensile process.Based on the Barkhausen effect and Magnetic Inducton effect of the Co-rich ferromagnetic microwires,we design and manufacture air flow sensor consist of the Co-rich ferromagnetic microwires array.The basic structure of the air-flow sensor is consist of Co-rich ferromagnetic microwires array and excitation-pickup coils.The Co-rich ferromagnetic microwires would generate stable and sharp induced voltage under alternating magnetic field excitation.The stable and sharp induced voltage generated a magnetic field which may induce the pick-up side ferromagnetic microwires array and can be detected by the pick-up coils.The sensor signal would reduce with the air-flow velocity because the microwires array would bend due to the air blow which decreased the induction effect between two microwires arrays.The experiment result also proved that the air-flow sensor based on Co-rich ferromagnetic microwires has excellent sensing performance.The sensing detection range is from 0.05m/s to 6.5m/s and the signal sensitivity is 0.143(m/s)-1.At last,we design and manufacture the bio-inspiration skin tactile sensor mimicing the human skin structure based on the fiber shape strain sensor and the air-flow sensor.The biomimic sensor is consist of by two parts,the first part is the ferromagnetic microwires exposured on the sensor surface which mimic the human fine hair;the second part is the ferromagneric microwires buried in the sensor which mimic the human skin.The first part is sensitive to tiny stimulus such as air-flow while the second part is sensitive to heavy weight such as contact force.Due to the different magnetization status of the Co-rich ferromagnetic microwires,two frequency were utilized to measure the force while the low frequency is 20 k Hz and the high frequency is 1MHz.The hairy skin tactile sensor has many excellent sensing functions: wide detection range(from 0.1m N to 25N),high signal sensitivity(6.9N-1),sensing air-flow velocity,outstanding abrasion resistance(maintain sensory function under hair abrasion and skin puncture),excellent durability(no sensory function degeneration under 10,000 cycles),estimate material hardness,estimate material electric and magnetic property(distinguish magnetic material,conductor material,insulation material).This article takes full advantage of the excellent mechnical and magnetic property,design and manufacture various type sensor which expand the application area of the ferromagnetic microwires.The hairy skin tactile sensor makes the ferromagnetic microwires find potential applications in smart robot field.