新型医用Ti-35Nb-4Sn-6Mo-9Zr和Ti-35Nb-1.3Mo-3.7Zr合金在林格溶液中的电化学腐蚀行为

采用开路电位、动电位极化曲线和电化学阻抗谱(EIS)测量方法研究了新型医用钛合金Ti-35Nb-4Sn-6Mo-9Zr和Ti-35Nb-1.3Mo-3.7Zr在林格溶液中的电化学腐蚀行为,计算了2种合金在林格溶液中的腐蚀电位(φcorr)、腐蚀电流(Icorr)及钝化电流(Ipass),并根据EIS曲线建立了等效电路进行参数分析,同时与Ti-6A1-4V(TC4)合金进行比较。结果表明:Ti-35Nb-4Sn-6Mo-9Zr、Ti-35Nb-1.3Mo-3.7Zr和TC4合金的Icorr和Ipass依次增大,而φcorr依次减小。EIS结果分析显示,3种合金在林格溶液中均可形成致密内层和疏松外层的双层钝化膜,其中致密内层钝化膜对合金表面的保护起主要作用。3种合金的致密内层的阻挡作用按TC4、Ti-35Nb-1.3Mo-3.7Zr和Ti-35Nb-4Sn-6Mo-9Zr的顺序递增。     

低弹性模量Ti-33Nb-4Sn,Ti-31Nb-3Zr-4Sn钛合金在模拟人工体液中的腐蚀行为研究

采用纳米压痕仪研究了Ti-33Nb-4Sn和Ti-31Nb-3Zr-4Sn合金的力学性能。采用动电位极化曲线、电化学阻抗谱研究了新型医用钛合金Ti-33Nb-4Sn、Ti-31Nb-3Zr-4Sn和对比合金Ti-6Al-4V在模拟人体体液中电化学腐蚀行为,并根据扫描电镜和X射线衍射仪对极化测试后的试样表面形貌和相结构进行观察。结果表明,Ti-33Nb-4Sn和Ti-31Nb-3Zr-4Sn合金具有较低的弹性模量;3种合金的腐蚀电流密度按Ti-6Al-4V、Ti-31Nb-3Zr-4Sn和Ti-33Nb-4Sn的顺序递增。     

模拟人体体液中放电等离子烧结生物医用Ti2448合金的腐蚀行为研究

利用动电位极化曲线和电化学阻抗谱方法研究了放电等离子烧结技术(SPS)制备的生物医用Ti-24Nb-4Zr-8Sn(Ti2448)合金在Hank's模拟人体体液中的电化学腐蚀行为及腐蚀机理,并与工业纯钛(TA1)和Ti-6Al-4V(TC4)合金进行了比较。结果表明:与TA1和TC4合金相比,在37℃的Hank's溶液中SPS烧结Ti2448合金具有最小的腐蚀电位与致钝电流密度、接近的腐蚀电流密度以及最大的极化电阻,3种材料耐腐蚀性能好坏依次为Ti2448TC4TA1。     

超弹性Ti-24Nb-4Zr-8Sn合金的马氏体相变研究

马氏体β型Ti-24Nb-4Zr-8Sn合金(Ti2448合金)在室温下表现出良好的超弹性能,可回复应变可达3.3%,明显高于Ti-6Al-4V合金和Ti-Nb二元超弹性合金。法国学者Y.Yang等利用拉伸试验、原位同步辐射X射线衍射(SXRD)、动态力学分析技术(DMA)研究了超弹性Ti2448合金的马氏体相变。实     

高强耐蚀Ti-Al-Nb-Zr-Mo合金的成分优化及组织和力学性能研究

以Ti80合金为基础,制备了Ti-5.5Al-3.0Nb-3.0Zr-1.2Mo合金,研究了其组织与性能。结果发现,Ti-5.5Al-3.0Nb-3.0Zr-1.2Mo合金的热处理组织呈均匀网篮状,力学性能与电化学腐蚀性能均表现优异。添加0.3%的Ni后合金组织得到细化,强度及电化学腐蚀性能得到进一步提升,塑韧性有所降低。     

SPS烧结Ti-35Nb-7Zr-5Ta合金在Ringer's模拟体液中的电化学腐蚀行为

采用放电等离子烧结技术制备了Ti-35Nb-7Zr-5Ta(Ti-Osteum)生物医用钛合金。以生物医用金属材料纯Ti(TA1)和Ti-6Al-4V(TC4)合金为对比材料,利用开路电位、动电位极化曲线和电化学阻抗谱等方法研究了该合金在Ringer's模拟体液中的电化学腐蚀行为及其腐蚀机理。结果表明:与TA1和TC4合金相比,SPS烧结的Ti-Osteum合金在模拟体液中具有最小的腐蚀电流密度和较小的钝化电流密度、较大的容抗弧以及接近的腐蚀电位,从而显示了优于TC4和TA1的良好耐腐蚀性能。SPS烧结Ti-Osteum合金在模拟体液中耐腐蚀性优异的主要原因是具有单相β型组织,并且表面出现稳定的复合氧化物钝化膜。     

蛋白含量对Ti-24Nb-4Zr-8Sn纳米晶合金在模拟唾液中电化学行为的影响

采用动电位极化曲线、电化学阻抗谱和Mott-Schottky曲线等电化学测试方法研究了Ti-24Nb-4Zr-8Sn(Ti2448)纳米晶合金在含有不同浓度的小牛血清蛋白(BSA)的模拟唾液中的电化学腐蚀行为。结果表明:Ti2448纳米晶合金在模拟唾液中能迅速形成具有n型半导体特征的致密完整的单层钝化膜。当加入低浓度的BSA(0.1 g/L)时,蛋白质在合金表面以吸附为主,合金的耐蚀性提高;当BSA浓度的增加到中、高浓度(≥1.0 g/L)时,蛋白质会在合金表面形成稳定性较差的络合物,从而导致合金的耐蚀性降低。     

SPS烧结Ti-35Nb-7Zr-5Ta合金在Hank's模拟人工体液中的电化学腐蚀行为

利用放电等离子烧结技术制备了生物医用Ti-35Nb-7Zr-5Ta(Ti-Osteum)合金,采用开路电位、动电位极化曲线和电化学阻抗谱方法研究了该合金在Hank's模拟人工体液中的电化学腐蚀行为及其腐蚀机理,并与纯Ti(TA1)和Ti-6Al-4V(TC4)合金进行了对比研究。结果表明:与TA1和TC4合金相比,SPS烧结Ti-Osteum合金在模拟人工体液中具有最小的腐蚀电流与钝化电流密度、最大的极化电阻以及接近的腐蚀电位,从而显示了良好的耐腐蚀性能,3种材料耐腐蚀性能高低依次为:Ti-OsteumTC4TA1;SPS烧结Ti-Osteum合金在模拟人工体液中耐腐蚀性能优异的主要原因是具有高的致密度、单相β型组织以及表面容易形成稳定的复合氧化物钝化保护膜。     

Ti-24Nb-4Zr-8Sn合金疲劳缺口敏感性

研究不同缺口半径和应力比对Ti-24Nb-4Zr-8Sn合金室温高周疲劳性能的影响.结果表明:缺口的存在明显降低合金的疲劳强度,缺口半径和应力比的变化对合金的组织及缺口敏感性影响不大,仅疲劳强度稍有变化.与其他类型常用钛合金相比较,Ti-24Nb-4Zr-8Sn合金具有低的室温疲劳缺口敏感性,这主要归因于其良好的室温塑性以及超弹性变形特点.     

生物医用Ti-Nb-Ta-Zr-Fe合金在林格溶液中的腐蚀行为（英文）

采用动电位极化方法研究Ti-25Nb-10Ta-1Zr-0.2Fe(质量分数%)(TNTZF)合金37℃下在林格溶液中的抗腐蚀性能,并在同样的条件下用Ti-6Al-4V-ELI(低间隙)合金做对比实验。结果表明:TNTZF比Ti-6Al-4V-ELI合金表现出更高的腐蚀电位,更低的腐蚀电流密度,更加稳定的钝化电流密度和更宽的钝化区间,因此具有更加优越的抗腐蚀性能。除此之外,在Ti-6Al-4VELI合金的表面钝化膜上观察到了点蚀现象,但是在TNTZF合金表面没有发现点蚀现象。XPS分析结果表明:TNTZF合金表面钝化膜由TiO_2基体以及Nb_2O_5、NbO_2、Ta_2O_5、ZrO_2、TiO和Ti_2O_3等氧化物共同组成,从而使得钝化膜更加稳定且保护作用更强,因此TNTZF合金比Ti-6Al-4V ELI合金表现出更加优越的抗腐蚀性能。     

Ta含量对Ti-6Al-3Nb-2Zr-1Mo-xTa合金力学性能和腐蚀性能的影响

系统研究了Ti-6Al-3Nb-2Zr-1Mo-x Ta(x=0,0.2,0.5,1.0,3.0,5.0)合金的微观组织、拉伸性能、夏比冲击韧性和耐海水腐蚀性。结果表明,经α+β两相区锻造后,Ti-6Al-3Nb-2Zr-1Mo-5Ta合金获得片层组织,Ti-6Al-3Nb-2Zr-1Mo-x Ta(x=0,0.2,0.5,1.0,3.0)均获得双态组织。XRD、TEM和选区电子衍射表明,在添加Ta元素后,Ti-6Al-3Nb-2Zr-1Mo-x Ta合金没有新相产生。对于双态组织Ti-6Al-3Nb-Zr-1M0-x Ta合金,随着Ta含量的增加,其Mo当量逐渐增加,导致其屈服强度、抗拉强度和显微硬度均有所提高。而Ta含量对冲击吸收功的影响规律与屈服强度和抗拉强度的影响规律相反,其大小与冲击断口剪切唇区面积一致。当Ta含量超过1.0%(质量分数)时,由于α和β相之间的标准平衡电位差逐渐增大,Ti-6Al-3Nb-2Zr-1Mo-x Ta合金的耐海水腐蚀逐渐降低。综合考虑强度、冲击韧性和耐海水腐蚀性能,Ti-6Al-3Nb-2Zr-1Mo-1Ta合金综合匹配性最好,具有良好的海洋工程应用潜力。     

Characterization of the Ti-10Nb-10Zr-5Ta Alloy for Biomedical Applications. Part 1: Microstructure, Mechanical Properties, and Corrosion Resistance

Ti-10Nb-10Zr-5Ta alloy was investigated as possible material candidate for replacing Ti6Al4V in medical applications. The alloy was prepared in a levitation melting furnace and characterized in terms of elemental and phase composition, microstructure, mechanical properties, and corrosion resistance in simulated body fluid and Fusayama Meyer artificial saliva solutions. The characteristics of the new alloy were compared to those of the Ti6Al4V alloy. The Ti-10Nb-10Zr-5Ta system was found to posses of a polyhedral structure consisting in α′ and β phases. X-ray structural analysis revealed a mixture of hexagonal α′ martensite (main phase, with grain size of about 21 nm) and β bcc phase. The Ti-10Nb-10Zr-5Ta alloy exhibited some better mechanical properties (Young modulus, tensile properties) and corrosion resistance (polarization resistance, corrosion current density, and corrosion rate), as compared to Ti6Al4V alloy.     

Enhancements of Passive Film and Pitting Resistance in Chloride Solution for 316LX Austenitic Stainless Steel After Sn Alloying

In the present work, the electrochemical behavior and properties of the passive film of a new Sn-alloyed 316 LX austenitic stainless steel were investigated. With the increase in Sn content in 316 LX austenitic stainless steel from 0 to 0.21%, the critical pitting temperature value increased from 32.6 to 38.8 °C, and the pitting potential increased from 0.252 V_(SCE) to 0.317 V_(SCE). Electrochemical impedance spectroscopy results showed that the corrosion resistance of passive film rose with the increase in Sn content, indicating a more stable passive film. The Mott–Schottky measurement revealed an n-type passive film with a decreased carrier concentration on the 316 LX austenitic stainless steel surface. The Cr, Sn~(2+) and Sn~(4+)(SnO, SnOHCl or SnO_2) enrichments were observed in the passive layer by X-ray photoelectron spectroscopy. The enrichment of Sn and Cr in the passive film can account for the enhanced pitting resistance of 316 LX austenitic stainless steel in chloride solution.     

Characterization of the Ti-10Nb-10Zr-5Ta Alloy for Biomedical Applications. Part 2: Wettability, Tribological Performance and Biocompatibility

The Ti-10Nb-10Zr-5Ta alloy, prepared in a levitation melting furnace, was investigated as a possible candidate for replacing Ti6Al4V alloy in medical applications. The sessile drop method, pin-on-disc and in vitro tests were used to analyze wettability, wear resistance, and biocompatibility of the new alloy. The characteristics of the Ti-10Nb-10Zr-5Ta alloy were assessed in comparison to those of the Ti6Al4V alloy. The Ti-10Nb-10Zr-5Ta system was found to have hydrophilic characteristics with similar contact angle as the Ti6Al4V alloy. In all environments (deionized water, simulated body fluid and Fusayama Meyer artificial saliva), the friction coefficient showed a stable evolution versus sliding distance, being similar for both alloys. On overall, the wear resistance of Ti-10Nb-10Zr-5Ta alloy was lower than that of Ti6Al4V for all testing environments. The Ti-10Nb-10Zr-5Ta alloy exhibited good biocompatibility characteristics at in vitro test compared to Ti6Al4V alloy. The cell viability on Ti-10Nb-10Zr-5Ta surfaces was higher than the one observed on Ti6Al4V samples, regardless the number of days spent in osteoblast-like cells culture. A high degree of cell attachment and spreading was observed on both alloys.     

X80管线钢钝化膜在各种高浓度NaHCO3溶液中的电化学行为

采用动电位极化曲线、恒电位极化曲线、电化学阻抗谱(EIS)、Mott-Schottky分析等电化学方法研究了X80管线钢在各种高浓度的NaHCO₃溶液中形成钝化膜的电化学行为。结果表明, X80管线钢钝化膜的稳定性和耐蚀性会受到NaHCO₃溶液浓度的影响。钝化膜电化学性质随HCO₃^-浓度升高而降低;内层Fe₃O₄的厚度不随HCO₃^-浓度变化,推测其形成与成膜电位有关;内外膜层厚度比随HCO₃^-浓度的升高而增大,钝化膜的稳定性和耐蚀性主要受外层γ-Fe₂O₃的影响。根据点缺陷(PDM)理论的分析认为,NaHCO₃溶液浓度升高时钝化膜稳定性和耐蚀性的降低与溶液电导率的升高和HCO₃^-在缺陷点处吸附作用的增强有关。     

Effect of enamel coating on long-term oxidation and hot corrosion behavior of Ti-24Al-17Nb-0.5Mo alloys

The effect of enamel coating on long-term isothermal oxidation at 700 ℃ and cyclic oxidation at 800 ℃ in air and hot corrosion resistance of Ti-24Al-17Nb-0. 5Mo in 75% (Na2SO4 K2SO4 ) 25% NaCl (mass fraction) molten mixed salts at 700 ℃ was investigated. The results indicate that Ti-24Al-17Nb-0.5Mo alloy exhibits relatively poor long-term oxidation resistance due to the formation of Al2O3 TiO2 Nb2O5 mixed scales and poor hot corrosion resistance due to the spallation of scales formed in molten (Ns, K)2 SO4 NaCl. Enamel coating can effectively protect Ti-24Al-17Nb-0.5Mo alloy from long-term oxidation at high temperature in air and remarkably improve the hot corrosion resistance of Ti-24Al-17Nb-0. 5Mo alloy, and can act as the barrier to suppress the migration of oxygen and corrosive ions into the substrate.     

铸态Ti-20Zr-10Nb-xMo合金的微观组织和耐腐蚀性能

采用X射线衍射仪(XRD)、光学显微镜(OM)、硬度测试、压缩试验和电化学工作站等研究了Mo含量对Ti-20Zr-10Nb-xMo(x=0,3,6,9,wt%)合金相结构、显微组织、力学性能以及电化学腐蚀性能的影响。结果表明,随着Mo含量的增加,Ti-20Zr-10Nb-xMo合金的相结构发生了α′+β→α″+β→β的变化,平均晶粒尺寸亦随着Mo含量的增加而逐渐降低;当Mo含量为9%时,合金的平均晶粒尺寸约为45 μm。通过Mo的添加,合金的抗压强度和屈服强度呈现先降低后升高的趋势,而显微硬度则先增大后降低;当Mo含量为9%时,合金的抗压强度最大,为1610 MPa,压缩应变为50.9%。未添加Mo的试验合金的自腐蚀电流密度最小,为33.19 nA·cm^-2,R_p值最大,为1531.52 kΩ·cm²,其耐腐蚀性最好。     

Sn含量对N36锆合金在LiOH水溶液中耐腐蚀性能的影响

比较了N36(Zr-1Sn-1Nb-0.3Fe)及低锡N36 (Zr-0.8Sn-1Nb-0.3Fe)锆合金样品在360 ℃/18.6 MPa/0.03 mol/L LiOH 水溶液中的耐腐蚀性能,发现N36提前发生腐蚀转折,转折后腐蚀增重远高于低锡N36。观察了腐蚀转折后合金样品氧化膜形貌及物相特征,发现在氧化膜断面上形成平行于氧化膜／金属界面的裂纹,而界面氧化膜呈"菜花"状生长;与N36相比,低锡N36氧化膜形貌显示断面裂纹相对较少,界面生长的氧化膜较为平整;随腐蚀速率的增加,断面裂纹增多,界面膜呈"菜花"状凸起越严重;氧化膜中产生的裂纹与四方相的转变有关。讨论了Sn对N36合金耐腐蚀性能影响的机理,认为固溶在α-Zr中的Sn含量是引起耐腐蚀性能差别的主要原因。     

550℃表面渗氧对Ti-6Al-4V合金耐磨性能的影响

对Ti-6Al-4V合金550℃的空气中渗氧60 h后的表面形貌、显微组织、成分、硬度、划刻性能和耐磨性进行研究,并与未处理的钛合金进行了比较.结果表明,渗氧后的钛合金表面粗糙度有所增加,表层形成约3.5μm厚的渗氧层,X射线衍射(XRD)检测到了锐钛矿相、金红石相、板钛矿相TiO2和Al2O3相.渗氧层的显微硬度和纳...     

Microstructure, mechanical, and anticorrosive properties of a new Ti-20Nb-10Zr-5Ta alloy based on nontoxic and nonallergenic elements

For an alloy to be suitable for use as an implant material, it must have a low specific weight and Young??s modulus, good mechanical properties that are similar to those of bone, and very good corrosion resistance and biocompatibility. In this study, we have developed a novel Ti-20Nb-10Zr-5Ta alloy that is composed of nontoxic, nonallergenic, corrosion-resistant elements. This alloy has low specific weight and Young??s modulus and good mechanical properties. It has a fine microstructure with a matrix that is mainly composed of the ?? phase and some ?? phase due to recrystallization during cooling. It shows elastoplastic behavior with a fairly linear elastic behavior and low Young??s modulus (59 GPa). In addition, its ultimate tensile strength, 0.2% yield strength, and hardness are higher than those of CP Ti, commercial Ti-6Al-4V, and similar ??-type alloys. It exhibited a very stable passive state and its electrochemical parameters and corrosion and ion release rates were better than those of CP Ti in Ringer??s solutions of different pH values that simulate the severe functional conditions of an implant; this is attributable to the beneficial influence of the alloying elements and to the better protective properties of the coated passive film.