Study On Microstructure And Properties Of Biomedical Degradable Zn-based Alloy Prepared By Microwave Sintering

Biomedical degradable metal materials provide temporary mechanical support for the injured tissue and completely degrade in the body without the need for a second operation to remove it.Compared with the other two biomedical biodegradable metals magnesium（Mg）and iron（Fe）,zinc（Zn）,as a new type of biomedical biodegradable metal materials,shows better biodegradable behavior.However,pure zinc lacks sufficient mechanical strength to meet the requirements of clinical applications for mechanical properties.Alloying is a simple and effective method to improve the mechanical properties of zinc.In this paper,biological functional elements selenium（Se）and copper（Cu）were selected as alloy elements,and biomedical degradable Zn-Se-Cu alloys were successfully prepared by microwave sintering process,and their microstructure,mechanical properties,biodegradability,anti-tumor properties and antibacterial properties were studied.The Zn-Se-Cu alloy prepared by microwave sintering has a microporous structure,and the second phase is Zn Se phase distributed along the edge of Zn particles and Cu Zn₅phase uniformly distributed in Zn matrix.With the increase of Cu content,the content of Cu Zn₅ phase in Zn-2Se-x Cu alloy（x=0,2,5 and 7 wt.%）increases accordingly,and compressive strength increase at first and then decrease.The hardness of Zn-Se-Cu alloy increases with the addition of Se and the increase of Cu content.The results of electrochemical experiments and static immersion experiments show that the degradation rate of Zn-Se-Cu alloy with different composition in Hanks simulated body fluid is of the same order of magnitude,and the degradation rate is 0.1～0.3 mm/year.The degradation rate of Zn-2Se alloy is slightly lower than that of pure Zn,but the addition of Cu promotes the degradation of Zn-Se-Cu alloy,and Zn-2Se-7Cu alloy has the highest degradation rate.The cytotoxicity and proliferation test and cell adhesion test of cal-27 human tongue squamous cell carcinoma cells show that Zn-2Se alloy had significant cytotoxicity to cal-27 cells.Through the results of antibacterial experiments,it was found that the addition of Cu significantly improved the antibacterial properties of Zn-2Se-x Cu（x=2,5和7 wt.%）alloy.This paper provides new composition design ideas and processing methods for the development of new biodegradable biomedical functional materials.Figures 32,Tables 14,References 196...