毕业论文---不同加工工艺对医用镁锌钇钕合金显微组织的影响.docVIP

不同加工工艺对医用镁锌钇钕合金显微组织的影响 摘 要 随着生物医用可降解材料研究的不断深入与发展，由于镁基合金具有良好的生物相容性、生物可降解性以及力学性能，逐渐引起了人们的广泛关注。镁是人体内必需的微量金属元素，具有良好的生物相容性和生物可降解性。随着血管内治疗技术的发展，血管内支架植入术已经成为了治疗心血管疾病最有效的方法之一。常用的血管支架材料包括了不锈钢、镍钛、钴铬合金等生物惰性材料，这些支架材料作为异物虽然能够长期存在于人体内，但会引起内膜的过度增生，造成15% ～ 30% 的术后再狭窄。除了术后再狭窄，这些不可降解的惰性金属支架还能够产生内皮功能紊乱、凝血、慢性炎症、血管与支架机械性能不匹配等生物相容性问题，这在一定程度上限制了金属血管支架在临床中的应用。而本文主要通过对医用镁锌钇钕合金的研究，采取不同的加工工艺以获得相应的结果，并通过相应的实验获得了下面相应的结果，实验表明： （1）普通凝固态 Mg-Zn-Y -Nd 合金经过三种不同挤压工艺挤压后，合金的晶粒发生显著细化。 （2）挤压后合金结构相的组成和分布发生明显的变化。 （3）挤压工艺在细化晶粒的同时会降低合金的耐腐蚀性能。 关键字：镁锌钇钕合金，晶粒，耐腐蚀性 Effect of ifferent Processing Technology for Medical Mg-Zn Alloy Microstructure Neodymium Yttrium Author: Abstract With the deepening and development of bio-degradable materials for medical research, because magnesium-based alloys have good biocompatibility, biodegradability and mechanical properties, gradually attracted extensive attention .Commonly used stent materials include stainless steel, nickel, titanium, cobalt-chromium alloys and other biologically inert materials, these scaffolds as though the long-term presence of foreign substances in the human body, but can cause endometrial hyperplasia, resulting in a 15% to 30% of patients restenosis. Restenosis after addition of these inert non-biodegradable metal stent can also produce endothelial dysfunction, coagulation, chronic inflammation, vascular stents and other mechanical properties mismatch problem of biocompatibility, the metal stent which limits to a certain extent in the clinical applications. The paper mainly through the study of medical magnesium-zinc alloy of neodymium, yttrium, take a different process to obtain the corresponding results and the corresponding results obtained by following the appropriate experiments showed that: (1) Ordinary solidified Mg-Zn-Y-Nd alloy extrusion process after three different extrusion, alloy grains occur significantly refined. (2) The composition and distribution of the extruded alloy structural phase change dramatically. (3) Extrusi