生物医用钛基非晶合金及其复合材料的制备与性能研究

发布时间：2018-04-12 00:34

本文选题：生物医用钛合金 + 制备工艺　；参考：《湘潭大学》2015年博士论文

【摘要】：钛合金由于具有良好的生物相容性、优异的耐腐蚀性能和力学性能,作为生物移植材料有着广阔的应用前景,而与同成分的晶态合金相比,非晶态合金具有较低的弹性模量,较高的强度和优异的耐磨耐蚀性能,因而作为生物医用移植材料,有着潜在的应用前景。然而,目前开发的钛基非晶合金还存在两个问题,限制了该非晶合金的实际应用。其一,非晶形成能力较好的钛基非晶合金中通常含有对人体有毒的元素,而不含有毒元素的钛合金,其非晶形成能力较差,难于制备出尺寸较大的块体非晶合金,其二,钛基非晶合金在室温下几乎没有塑性。因此,开发出不含对人体有害元素且具有一定非晶形成能力钛基非晶合金,并制备成大块,同时改善非晶合金的室温塑性,是促进钛基非晶合金作为生物移植材料在实际应用中的关键。为此,本文首先通过非晶合金形成的热力学和动力学理论分析,设计出了两种不含有毒元素的Ti-Zr-Ta-Si-Sn和Ti-Zr-Ta-Si-Nb非晶合金体系,并分别采用单辊甩带法和水冷铜模吸铸法制备了Ti-Zr-Ta-Si-Sn非晶合金薄带和高强Ti-Zr-Ta-Si-Nb合金,研究了Sn元素和Nb元素对合金非晶形成能力及其耐蚀性能和力学性能的影响,在此基础上,采用粉末冶金和高压烧结的方法制备出了块体钛基非晶基及其复合材料,探讨了制备工艺对Ti基非晶及其复合材料显微组织、热力学行为、力学行为的影响及其机理。论文创新性结论如下:1.开发了一种不含有毒元素的Ti-Zr-Ta-Si-Sn非晶合金,并采用甩带法制备出了该非晶合金薄带,研究了Sn元素对(Ti60Zr10Ta15Si15)100-x Snx(x=0,4,8 at.%)非晶合金的非晶形成能力、热力学行为和腐蚀行为的影响。研究表明,采用甩带法,可成功制备出(Ti60Zr10Ta15Si15)100-x Snx(x=0,4,8 at.%)非晶合金薄带,随着Sn的增加,合金的非晶形成能力略有下降;在该合金体系中加入Sn可促进非晶合金表面致密的钝化膜的形成,从而提高了合金的耐腐蚀性能;Sn的加入对该非晶合金的显微硬度和弹性模量也会产生重要影响,分析结果表明,Sn的加入可改变该非晶合金体系的自由体积,从而影响非晶合金的力学性能。2.采用Nb部分替代Ti-Zr-Ta-Si非晶合金中的Ta元素,开发出Ti-Zr-Ta-Si-Nb系非晶合金体系,并采用水冷铜模吸铸法制备出了Ti60Zr10Si15Ta15-x Nbx(x=0,3,7,11 at.%)合金。研究结果表明,虽然从理论分析上可知用Nb部分替代该非晶体系中的Ta有助于提高非晶合金的非晶形成能力并降低合金成本,但采用水冷铜模吸铸法难于制备Ti60Zr10Si15Ta15-x Nbx(x=0,3,7,11 at.%)块体非晶合金,对铸态的合金显微组织和力学性能分析测试结果表明,该合金由β-Ti及细小晶化相Ti2Zr、Ti Si、Si3Ti2Zr等相组成,其中Ti60Zr10Si15Ta8Nb7的断裂强度高达2150 MPa;该合金在磷酸缓冲盐溶液中表现出优良的耐蚀性能,且随着Nb含量的增加,其耐腐蚀性能增加,但其耐蚀性能低于非晶态的Ti60Zr10Ta15Si15。3.用机械球磨法制备了非晶态的Ti60Zr10Ta15Si15粉末,并采用高压烧结法制备出了块体Ti60Zr10Ta15Si15非晶合金。研究发现,球磨工艺参数对Ti合金粉末非晶化效率有重大影响,当球料比为20∶1,大小球的质量比为1∶2时,转速为350 rpm时,且分散剂占粉末质量的0.2%时,球磨60 h,钛合金粉末的非晶化效率最高;温度、压力对烧结材料的显微组织和力学性能都有重要的影响,在过冷液相区内(780 K)高压烧结Ti60Zr10Ta15Si15合金,非晶未发生晶化。而在高于晶化温度(820 K)下烧结,非晶态合金发生了明显的晶化。更高的烧结压力(5 GPa)未导致粉末发生明显的晶化,且使得材料的孔洞分布更均匀,组织更致密,弹性模量和断裂强度分别得到提高。耐磨性能更好,维氏硬度更大。4.通过在钛非晶粉末中添加纯钛粉,并采用高压烧结的的方法制备出了钛非晶基复合材料。结果表明,纯钛的体积分数和烧结保压时间对非晶复合材料的显微组织和室温压缩性能具有重要的影响。在烧结过程中,混合物中没有出现新的物相,烧结过程主要是非晶相和纯钛相的物理扩散控制,复合材料具有一定的塑性;保压时间对非晶复合材料的显微结构、显微组织和室温压缩性能也具有重要的影响。对烧结材料的物相鉴定显示,当保压时间从10 min增加到120 min,没有新的相产生,且颗粒结合更紧密,导致复合材料力学性能更好。
[Abstract]:Titanium alloy has good biocompatibility, excellent corrosion resistance and mechanical properties, as biological graft material has broad application prospect, and amorphous alloy with the same composition as compared to amorphous alloy has a low elastic modulus, high strength and excellent abrasion resistance and corrosion resistance, so as a biomedical implant materials, has a potential application prospect. However, titanium based amorphous alloy is also the development of the two problems, limits the practical application of the amorphous alloy. On the one hand, the formation of amorphous Ti based amorphous alloy has good ability in general on the human body contains toxic elements, but does not contain toxic elements in titanium alloy the glass forming ability is poor, it is difficult to fabricate large bulk amorphous alloy, the titanium based amorphous alloy at room temperature almost no plastic. Therefore, the development of free of harmful elements and has a certain The forming ability of amorphous Ti based amorphous alloy, and prepared into blocks, while improving the ductility of amorphous alloys, Ti based amorphous alloy is promoted as a key biological graft material in practical application. Therefore, this paper through the thermodynamics and kinetics of amorphous alloy formation theory analysis, design and Ti-Zr-Ta-Si-Sn Ti-Zr-Ta-Si-Nb two does not contain toxic elements of the amorphous alloy system, and adopts single spinning and water-cooled copper mold suction casting method to prepare Ti-Zr-Ta-Si-Sn amorphous alloy ribbons and high-strength Ti-Zr-Ta-Si-Nb alloy, to study the Sn element and the Nb element of amorphous alloy formation and corrosion resistance and mechanical properties of this. Based on the prepared block based and titanium based Amorphous Composites by powder metallurgy method and high-pressure sintering system, discusses on the microstructure of Ti amorphous alloys and their composites prepared by thermal. The behavior, influence the mechanical behavior and its mechanism. The innovation of this paper are as follows: 1. the development of a does not contain toxic elements of Ti-Zr-Ta-Si-Sn amorphous alloy, and the ribbon was prepared by the amorphous alloy ribbons of Sn elements on 100-x Snx (Ti60Zr10Ta15Si15) (x= 0,4,8 at.%) amorphous formation the ability of amorphous alloy, thermal behavior and corrosion behavior. The results show that the melt spinning method, can be successfully prepared (Ti60Zr10Ta15Si15) 100-x Snx (x=0,4,8 at.%) amorphous alloy ribbon, with the increase of Sn amorphous alloy forming ability decreased slightly; adding Sn can promote the formation of passive film the surface density of the amorphous alloy in this alloy system, thereby improving the corrosion resistance of alloy; adding micro hardness and elastic modulus of the amorphous alloy Sn would also influence the analysis results show that the addition of Sn can change the amorphous The free volume of gold system, thus affecting the mechanical properties of.2. amorphous alloys by partial substitution of Nb Ti-Zr-Ta-Si non Ta amorphous alloy elements in the development of Ti-Zr-Ta-Si-Nb amorphous alloy system, and the use of water-cooled copper mold suction casting was prepared by Ti60Zr10Si15Ta15-x Nbx (x=0,3,7,11 at.%) alloys. The results show that although in theory we use Nb to replace part of the amorphous Ta system helps to improve the glass forming ability of amorphous alloy alloy and reduce the cost, but by the water-cooled copper mold suction casting method to prepare Ti60Zr10Si15Ta15-x Nbx (x=0,3,7,11 at.%) bulk amorphous alloy, according to the analysis of microstructure of as cast alloy and mechanical performance test the result, the alloy is composed of beta -Ti and fine crystalline phase Ti2Zr, Ti Si, Si3Ti2Zr and other phases, the fracture strength of Ti60Zr10Si15Ta8Nb7 is up to 2150 MPa; the alloy in phosphate buffer salt solution table The excellent corrosion resistance, and with the increase of Nb content, the corrosion resistance increased, but its corrosion resistance is lower than that of the amorphous Ti60Zr10Ta15Si15.3. Ti60Zr10Ta15Si15 was prepared by mechanical ball milling powder is amorphous, and the high pressure sintering prepared bulk amorphous Ti60Zr10Ta15Si15 alloy. The study found that milling process parameters on Ti the efficiency of amorphous alloy powder has a significant effect, when the ball material ratio is 20: 1, quality of the size of the ball is 1: 2, the speed is 350 rpm, and accounted for 0.2% of the mass of powder dispersing agent, 60 h of milling titanium alloy powder, the highest amorphization efficiency; temperature are important effect of pressure on the microstructure and mechanical properties of sintered materials, in the supercooled liquid region (780 K) Ti60Zr10Ta15Si15 amorphous alloy high pressure sintering, not crystallize. In higher crystallization temperature (820 K) under the sintering of amorphous alloy has obvious The crystallization. The sintering pressure higher (5 GPa) did not cause obvious crystallization of powder, and makes the hole material distribution is more uniform, more compact structure, elastic modulus and fracture strength were improved. The better wear resistance, hardness of Vivtorinox greater.4. by adding titanium in titanium powder and amorphous powder. The system of the high pressure sintering method prepared Ti amorphous matrix composites. The results showed that the volume fraction of pure titanium and sintering has important influence on the microstructure pressure on Amorphous Composites and compressive properties at room temperature. During the sintering process, the mixture do not appear in the new phase, the sintering process is mainly amorphous and pure titanium physical diffusion control, composite material has certain plasticity; holding time on Microstructure of Amorphous Composites, microstructure and compressive properties at room temperature also has an important effect on the sintering material phase. The identification shows that when the holding time increases from 10 min to 120 min, there is no new phase, and the combination of particles is more compact, which leads to better mechanical properties of the composite.

【学位授予单位】：湘潭大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TG139.8;TB33

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