Effect Of Electrodeposition Process On Microstructure On Iron And Its Alloy Films

As human civilization continues to move forward,so does modern medicine.As of today,biomedical metal materials have evolved into a third generation,each of which continues to benefit humanity,and research into the materials themselves will continue to advance.In this paper,we focus on iron and its alloys in biomedical metallic materials,prepare them using a simple,convenient and fast electrodeposition method,and study the effect of the electrodeposition process on pure iron films and Fe-La-P alloy films.The effects of XRD,SEM and EBSD on different processes are explored.Finally,a simple corrosion test was performed on the ferroalloy film and the morphological results were observed using SEM.For electrodeposition of pure iron films,the main process variables used are the arrangement of the electrodes and the time of electrodeposition.When the electrodes are arranged in parallel,with the increase of time,pure iron grain began to grow gradually,and from the beginning of the orientation of the no orientation gradually became obvious,the film pre-growth is faster,and the rate gradually slowed down.When the electrodes are vertically aligned,the change in the area ratio of the cathode to the anode leads to a change in the electric field line near the cathode,and the result shows that the competition in the relationship of thin film grain-shaped nuclei is greater than the growth,the overall grain is smaller,and the orientation has been weaker with increasing time,but the growth rate of the film in the same time is 1.3² times that under the parallel alignment.For electrodeposition of Fe-La-P alloy films,the main process variables used are current density,inducer,pH of the solution and electrodeposition time.When the current density increases,the cathode overpotential increases,polarization is enhanced,Fe-La-P compounds increase,La content increases;when the current density is too large,hydrogen precipitation intensifies,negative effects appear,Fe-La-P compounds decrease,La content decreases.H3PO4 acted as an inducer in the experiment and promoted the completion of Fe-La-P compound-induced co-deposition.The pH changes the H⁺activity of the solution and affects the presence form of the citrate root ligand,the H+activity is high at pH=2,the H₂Cit^-ligand complexation is the best,which can effectively enhance the polarization effect,the Fe-La-P compound has the best morphology and does not agglomerate.The excessive prolongation of the electrodeposition time can not effectively increase the content of Fe-La-P compounds in the alloy film,due to the electrodeposition time will lead to an increase in electrode area,indirectly affecting the current density,ultimately showing a trend of Fe-La-P compounds first increase and then decrease.The optimum process for electrodeposition of Fe-La-P alloy films under the present experimental conditions was I_A=4A·dm^-2 with the addition of H₃PO₄,pH=2 and t=5min.The Fe-La-P alloy films obtained by the optimal process were placed in saline for a simple corrosion test and morphological observation of the alloy films with different corrosion times.The Fe-La-P compound is corroded to a flocculent form and can be spread uniformly on the film surface,with no pitting detected on the film.