Mechanism And Experimental Study Of Titanium Alloy Electro-Assisted Light-Induced Colloidal Jet Polishing

Titanium alloy artificial joint,as a substitute for bone implanted into the human body,needs to bear the functions of support and movement in the human body,and the long-term and stable use of artificial joint in the human body requires good surface quality,so the processing of titanium alloy artificial joint is required to be high.Titanium alloy is a kind of difficult-to-machine material.The traditional machining methods have low machining precision and the surface of titanium alloy has surface damage after machining,and the surface of artificial joint is complex curved surface,which limits the application of some finish machining methods in titanium alloy artificial bone and joint.In order to realize the precise and efficient machining of complex surface of titanium alloy artificial bone and joint,the basic research on electricity-assisted and light-induced colloid jet polishing of titanium alloy was carried out in this paper.The polishing technology utilizes the action of an electric field to increase the reaction probability of nanoparticles and titanium alloy surface materials under the action of photocatalysis,thereby improving the efficiency of colloid jet polishing.In this paper,the machining mechanism of electricity-assisted and light-induced colloid jet polishing titanium alloy was studied,and the flow field and electric field of nanoparticle colloid jet were simulated.Firstly,the action mechanism of external electric field on nano-particle colloid jet machining was analyzed,and the force of nano-particles in high-speed jet polishing slurry in the flow field and electric field was analyzed,and the action model of nano-particle colloid jet impacting the workpiece surface was established.The results show that the electric field can effectively increase the amount of hydroxyl radicals in the nanoparticle colloid jet,thus improving the polishing efficiency of the colloid jet.Then based on the theory of computational fluid dynamics（CFD）,two simulation models of colloid submerged jet polishing and non-submerged jet polishing are established,and the flow field simulation of three models of workpiece surface（flat,convex,concave surface）is carried out,and the distribution law of static pressure and velocity of fluid on the three workpiece surfaces under different process parameters is obtained;The electric field distribution in the submerged jet and non-submerged jet machining area is simulated,and the distribution of voltage and current density on the workpiece surface under different process parameters is obtained.Finally,On the self-made experimental equipment of electricity-assisted and light-induced colloid jet polishing,the electricity-assisted and light-induced colloid jet polishing experiments of titanium alloy were carried out,and the adsorption of titanium alloy on the surface of the polishing colloid jet was detected by scanning electron microscopy,Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy.The adsorption of Ti O₂ nanoparticles on the surface of TC4 titanium alloy before and after submerged jet and non-submerged jet adsorption was obtained,and the results showed that the adsorption of Ti O₂ nanoparticles on the surface of TC4 titanium alloy after submerged jet adsorption was more than that of non-submerged jet.Electro-assisted light-induced colloid submerged jet and non-submerged jet polishing experiments of titanium alloy were carried out,and the two-dimensional,three-dimensional morphology and surface roughness of TC4titanium alloy polished by submerged jet and non-submerged jet were characterized and analyzed by atomic force microscopy.The results show that the surface of titanium alloy can be well polished by electric-assisted light-induced colloid jet polishing,and the electric-assisted light-induced colloid jet polishing technology can be used for the surface processing of medical titanium alloy artificial joints.