Basic Research On Graphene Composite Particle Injection Molding Process

Graphene is a hexagonal planar thin film composed of carbon atoms and is one of the most promising new materials.It has good mechanical and electrical properties and is widely used in various fields,such as medical and new energy.Batteries,mobile communications,aerospace,etc.,have extremely high research value.Using it as a reinforcing base to compound with other materials makes the composite material have both excellent performances.However,due to the large specific surface of graphene,graphene has poor fluidity,and it is very easy to agglomerate and not uniformly dispersed in the matrix material,which affects The performance of composite materials,therefore,how to achieve effective controllable dispersion of graphene in the matrix is a key technology that needs to be solved urgently.In this paper,two technical routes are designed to solve this problem based on the successful preparation of graphene composite particles.The method of combining simulation and experimental research is to study the binding behavior of graphene composite particles and semi-solid phenolic resin matrix,to achieve controllable dispersion in the ceramic matrix,and to obtain the best process parameters to achieve the predetermined goal.Performance graphene devices provide the possibility,and have important research significance and application prospects.Route 1 uses semi-solid phenolic resin as the matrix,using a combination of numerical simulation and experimental verification to study the behavior of multiple graphene composite particles impacting the semi-solid phenolic resin matrix at different velocities,revealing the bonding mechanism of the two.Studies have shown that the greater the impact velocity of the particles,the more severe the plastic deformation of the two,and the more energy the composite particles transfer to the matrix.At this time,the matrix becomes viscoelastic and the more conducive to bonding,when the impact velocity reaches 600 m / s,The phenomenon of adiabatic shear instability occurs,the surface of the substrate is broken,and the composite particles can be completely embedded in the body.When the impact speed reaches 700 m / s,the rebound phenomenon between particles occurs,and the combination efficiency decreases;at the same time,the graphene composite particle group measured in the experiment Compared with the matrix binding depth and the simulation data,it is found that the binding depth is steep at 600 m / s and is larger than the diameter of the particle.At the same time,it is found that the binding amount of the two is also the largest at this speed.According to the analysis,the optimal impact velocity of graphene composite particle group injection molding is 600 m / s.Route two combines injection molding and light curing rapid prototyping,designing a new type of dispersive nozzle,debugging a new three-dimensional mobile platform,mixing mullite ceramic powder with photosensitive resin to produce ceramic slurry,and studying graphene compounding under different process parameters The dispersion effect of particles in the ceramic matrix.The research team first ensured that the pressure ratio of the dispersion nozzle = 1 under certain process parameters,adjusted the direct jet pressure and swirl pressure of the nozzle,sprayed graphene composite particles into ceramic pastes with different solid contents,and performed ultraviolet curing.Observe the combined state of the two to determine the best direct jet pressure and ceramic slurry solid content.The experiment found that the bonding depth of the two decreases with the decrease of the pressure ratio at the same solid content.The viscosity of the 50% and 45% solid content ceramic slurry is too high,and the graphene composite particles cannot be fully embedded in the matrix,but when the pressure ratio When the process parameter is 1 = 0.4MPa / 0.4 Mpa and the solid content is 40%,the graphene composite particles are completely embedded in the substrate,so the solid content of the ceramic slurry is determined to be 40% and the direct jet pressure is 0.4Mpa.ANSYS was used to simulate the effects of different pressure ratios = straight jet pressure / swirl pressure and jet distance on the dispersion effect of graphene composite particles on the ceramic matrix.The analysis shows that the smaller the pressure ratio,the stronger and more pronounced the external swirling airflow at the nozzle outlet is,which is more conducive to the dispersion of particles.Afterwards,when the swirl flow is greater than the direct jet flow,the two collide,resulting in a split flow.When the swirl flow in the cavity is dominant,the air flow dispersion is gradually uniform and the dispersion range increases,but when the larger the swirl flow and the direct jet flow are not in equilibrium,The airflow in the cavity is inclined.At the same time,the analysis software is used to grid the picture,and the standard deviation of the ratio of the particles to the grid is analyzed to evaluate the uniformity of the particle dispersion.The smaller the standard deviation,the better the dispersion effect.When the pressure ratio is k = 0.4MPa / 0.8MPa,the standard deviation is the smallest,which is 0.2124.At this time,the particle dispersion effect is the best,k = 0.4MPa / 0.8MPa is the best pressure ratio;as the spray distance increases,the airflow The smaller the effect,the faster the graphene composite particles are embedded in the matrix,and the dispersion range is increased to a maximum of 1.5 times the nozzle outlet;when the spray distance is 0.05 m,the standard deviation of the particle dispersion effect is at least 0.0709,to get the best spray Distance;and through experiments to verify,at the same time get the fitting curve of the curing thickness of the ceramic matrix and curing time,to obtain the best curing time of graphene composite particles fully embedded in the matrix.