High-nitrogen austenitic stainless steel for vascular stent and application thereof

Abstract

The invention provides a high-nitrogen austenitic stainless steel material for a vascular stent, which comprises the following chemical components in percentage by weight: 16-20% of Cr, 12-20% of Mn, 1-3% of Mo, 0.5-2% of Cu, no more than 0.05% of Ni, 0.7-1.2% of N, 0.5-8% of W, 0.05-0.5% of RE, no more than 0.08% of C, 0.3-4% of Si, no more than 0.010% of S, no more than 0.02% of P and the balance of Fe, wherein RE is a rare-earth element. The high-nitrogen stainless steel provided by the invention is mainly used for vascular stent processing; the elements of copper, nitrogen and rare earth are added to increase the blood compatibility of the stainless steel; and the tungsten alloy is added to increase the density of the stainless steel. The stainless steel has excellent visibility under X rays, contains no potential toxic element nickel, can be used in the aspects of surgical implants, medical appliances, food and catering appliances, jewelry and other stainless steel products which are always in contact with a human body, and can also be used in the fields of chemical engineering, environment protection and the like.

Description

technical field [0001] The invention belongs to the field of alloys, and in particular provides a high-nitrogen austenitic stainless steel for vascular stents. Background technique [0002] Atherosclerosis is a common disease that threatens human health in recent years. Coronary artery stenting is a very important method for revascularization in patients with coronary atherosclerotic heart disease. Nowadays, the problem of restenosis after coronary artery stenting has been greatly improved with the emergence of drug-eluting stents (DES), but the mid- and long-term effects of drug-eluting stents due to incomplete or delayed endothelialization In-stent thrombosis may again increase the incidence of in-stent restenosis. At present, it is generally believed that in-stent restenosis is mainly caused by the migration and excessive proliferation of smooth muscle cells induced by the mechanical stimulation of the intima by the stent. Although the drug-eluting stent improves and de...

AI Technical Summary

Problems solved by technology

In China, the Institute of Metal Research, Chinese Academy of Sciences took the lead in carrying out research on nitrogen-strengthened austenitic nickel-free stainless steel. The authorized patent is "a medical implantable austenitic stainless steel material" (patent number: 03110896.2). The nitrogen content of tentenitic stainless steel is 0.4% to 0.7% (mass content), but its austenite stability is poor, and its density is only 7.7kg m -3 , poor visibility after being processed into a fine mesh stent

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