Studies on Biocompatibility of Mg-4.0Zn-1.5Sr Alloy with Coated of the Laser Surface Processing Combining Alkaline Treatment

摘要

The surface modification of biomaterial Mg-4.0Zn-1.5Sr alloy has been done by means of laser surface processing combining alkaline treatment process, as well as the biocompatibility of Mg-4.0Zn-1.5Sr alloy with and without coatings has been analyzed comparatively. The results indicate that the optimal parameters of laser surface processing are that the power is 3 kW, the current 200A, the width 1mm, the defocus amount 135mm and the scanning speed 1mm/s. The optimal parameters of alkaline treatment are that the solution is NaOH, the concentration 0.5 mol/L, the temperature 80 °C and the time 12 h. After alkaline treatment the surface is smooth and compact. The hemolysis rate of 1 d, 3 d, 5 d for uncoated alloy is 1.04%, 0.8% and 4.56%, respectively, which is less than 5%, and for Mg-4.0Zn-1.5Sr alloys with coated of the laser combining alkaline treatment, the hemolysis rate of 1 d, 3 d, 5 d is 0.62%, 1.24% and 0.83% respectively, which is also less than 5%. Therefore, the phenomenon of hemolysis for the alloy with and without coated will not occur. In addition, HR on coated with the laser combining alkaline treatment have larger decline, and less volatility than that without coated, which is express that surface treatment of the alloy has more application prospects. RGR value with coated of laser combining alkaline treatment is 105.7%, 106.0%, 110.4%, respectively which cultivation for 1 d, 3 days, 5days and slightly higher than that of without coated, which isl00%, 108.8% and 101.8%, respectively. According the standard of cell cytotoxicity, for the alloy with and without coated it is zero level cytotoxicity, suitable for used of biomaterial.