Production status of titanium alloy materials for medical devices in China
Up to now, pure titanium and TC4 titanium alloy are still the largest and most widely used traditional main materials for surgical implants in the world, accounting for more than 80% of the global biomedical titanium alloy market. At present, the titanium and titanium alloy processing materials for surgical implants produced in China involve plate (thickness 0.8-25mm), rod and wire (diameter 1-90mm). The supply state can be cold rolling, hot working and annealing.
At present, GB/T 13810-2007 stipulates that the microstructure of titanium alloy additions TC4, TC4ELI and TC20 should be graded according to the microstructure rating chart in Appendix A, which is derived from YY/T0512-2009/ISO 20160-2006 "Classification of microstructure of metal materials for surgical implants α+β two-phase titanium alloy rods". Due to the different processing processes of titanium alloy sheet and bar, the microstructure chart specified in Appendix A is only applicable to the grade of α+β two-phase titanium alloy bar, and not applicable to the grade of α+β two-phase titanium alloy sheet.
Chinese and American medical titanium alloy grades and standards related information
Although the Chinese national standard clearly stipulates that the microstructure grading type of TC4 and TC20 titanium alloy should conform to the α+β double-phase structure of A1-A9, most domestic titanium materials are A3-A5 grade microstructure with poor quality stability when supplied. And the United States imported titanium microstructure can achieve fine crystallization A1 - A3 organization, bar diameter of 15 mm below the small specification can reach grade A1 (such as axis of alpha, beta phase grain size less than 10 microns), thus has good toughness, corrosion resistance and mechanical cutting performance, this causes our country artificial joints, dental implant, spinal internal fixation system and other high-end medical equipment products processing still needs a large number of imported foreign quality of TC4 titanium alloy material, and domestic medical titanium main meet domestic mid-range of medical equipment products such as bone plate and bone screws, etc.
