新型抗菌功能医用金属研究

不锈钢、钛及钛合金等医用金属材料已广泛应用于骨科、齿科及心血管介入等医疗领域,生物可降解镁合金是正在研究发展的新型医用金属材料,具有诱人的临床应用前景。面对目前『临床上亟待解决的植入物引发的细菌感染问题,开展医用金属材料的抗菌功能研究意义重大,也是实现金属材料结构／功能一体化发展的新探索。简要介绍了作者近年来在不锈钢、钛合金、可降解镁基金属等医用金属材料的抗菌功能研究方面的主要进展,并展望了抗菌医用金属材料的临床应用前景。     

Corrosion performance of titanium and titanium stabilised stainless steels

Abstract

Titanium and its alloys provide industry with a number of materials which are strong, light, and very corrosion resistant. In addition, titanium is added as an alloying constituent to some stainless steels to act as a stabiliser during welding. Over the past 30 years titanium alloys have been increasingly used in process industries, and wherever ‘nil corrosion’ is considered to be an essential design feature. The main drawback to titanium usage has been relatively high cost, but freedom from plant corrosion failures, reduced downtime for maintenance, and the increasing availability of titanium have made this metal and its alloys an attractive choice in recent years. Applications include process vessels, heat exchangers, marine fittings, offshore components, pump castings, and other applications where materials encounter a hostile service environment. Nevertheless, titanium and its alloys are still subject to some forms of corrosiveattack, such as galvanic corrosion, hydrogen absorption, erosion corrosion, and crevicecorrosion. Special welding procedures are also required, which, if ignored, can lead toserious problems. This paper outlines a number of recent investigations into some problems encountered in industrial and marine environments, where both titanium metal and titanium stabilised stainless steels have suffered unexpected corrosion attack. The case histories described illustrate that titanium may show unexpected corrosion problems if certain aspects of its corrosion behaviour are overlooked.     

Biomedical titanium alloys and their additive manufacturing

Titanium and its alloys have been widely used for biomedical applications due to their better biomechanical and biochemical compatibility than other metallic materials such as stainless steels and Co-based alloys.A brief review on the development of the b-type titanium alloys with high strength and low elastic modulus is given and the use of additive manufacturing technologies to produce porous titanium alloy parts,using Ti–6Al–4V as a reference,and its potential in fabricating biomedica replacements are discussed in this paper.     

Magnesium as a biodegradable and bioabsorbable material for medical implants

For many years, stainless steel, cobalt-chromium, and titanium alloys have been the primary biomaterials used for load-bearing applications. However, as the need for structural materials in temporary implant applications has grown, materials that provide short-term structural support and can be reabsorbed into the body after healing are being sought. Since traditional metallic biomaterials are typically biocompatible but not biodegradable, the potential for magnesium-based alloys in biomedical applications has gained more interest. This paper summarizes the history and current status of magnesium as a bioabsorbable implant material. Also discussed is the development of a magnesium-zinc-calcium alloy that demonstrates promising degradation behavior.     

Influence of shielding gases on quality and efficiency in gas shielded arc welding

This article describes the physical principle of function and some examples of the application of the keyhole TIG (K-TIG) welding process.

Due to its specificity, this welding process has been shown to be valid for performing full penetration welds, even with a single pass, on various types of materials, particularly valuable materials: indeed, it is very well suited to being applied to such materials as austenitic stainless steel, titanium and its alloys, nickel alloys, the austeno-ferritic (duplex) steels, obviously in addition to the C–Mn steels.

This article describes the physical principle of functioning of K-TIG welding process, besides some examples of application in different working situations.

Such a welding process has proved itself to be suitable to execute Mel-nil-thickness welding of different kinds of metallic materials (also with a single pass). This welding process is particularly suited to be applied on the most valuable materials, like: inox stainless steel, titanium and its alloys, nickel alloys, duplex steel, C–Mn steels.     

蛋白质作用下医用金属材料的腐蚀行为研究进展

基于蛋白质与医用金属间的吸附与螯合作用,综合评述了蛋白质作用下医用金属材料（钛及钛合金、不锈钢、钴基合金、镁合金等）腐蚀行为的研究进展,着重讨论了白蛋白、纤维蛋白原及血清影响下医用金属材料的腐蚀行为及机理,并指出了目前研究中存在的科学问题与未来研究的发展方向。     

工业材料的微生物腐蚀

综述了碳钢,不锈钢,铝合金,铜合金,镍合金,钛合金,混凝土及其它非金属材料微生物腐蚀研究中的一些新进展。     

等离子喷涂人工骨涂层材料

等离子喷涂是一种常用的生物医用材料表面改性技术,被广泛应用于钛等金属人工骨的表面改性.为了满足人工骨涂层的临床应用需要,近年来发展了一些新的涂层材料和后处理工艺技术.利用火焰蒸汽处理技术对等离子喷涂羟基磷灰石涂层进行后处理,提高了涂层的结晶度,降低其在体液中的降解.经碱处理的等离子喷涂钛涂层,生物活性有了明显的改善.等离子喷涂硅灰石和硅酸二钙陶瓷是一类不同于传统磷酸钙系的新型生物活性材料,其性能和结构已被初步研究.同时介绍了等离子喷涂人工骨涂层材料在这几个方面的近期研究进展.     

不锈钢管和钛管的气动泄漏密实性试验新方法

分析了水下气压试验、水压试验和涡流或超声波无损检测等3种泄漏密实性试验在不锈钢管和钛管泄漏量检查中的优缺点,介绍了气动泄漏试验的原理、方法、判别准则及其优越性。分析认为,在不锈钢管和钛管的泄漏密实性检测中,气动泄漏试验的灵敏度高,且全自动,但其关键是设计或采购具有高灵敏度压力或压差的传感器,并采用激光打孔法制作0.076～0.152mm细微泄漏孔的标样管。     

难加工材料的特性及其应用前景

高温合金、钛合金、不锈钢、超高强度钢以及高温结构陶瓷等难加工材料，主要用于航空、航天、舰船、核电、石油化工、汽车和坦克等工业，随着材料科学和先进制造技术的发展，难加工材料有更广阔的应用前景。本文介绍了难加工材料的内涵、性能及应用前景。     

Electrochemical behaviour of titanium coated stainless steel by r.f. sputtering in synthetic sweat solutions for electrode applications

The r.f. sputtering technique was used to deposit titanium thin films on stainless steel substrates, aiming at the application of the coated samples as skin contact materials for “dry” active electrodes. In this work the electrochemical behaviour of the coated samples was investigated in synthetic sweat solutions and their performance was compared with that of uncoated stainless steel and bulk titanium. The characterisation of the samples was carried out by electrochemical techniques and scanning electron microscopy. The coated samples displayed corrosion resistance values in synthetic sweat solutions much higher than stainless steel samples and of the same order of the values measured for bulk titanium in the same conditions.     

钛合金与不锈钢的钎焊和扩散焊技术研究现状及发展趋势

综述了钛及其合金与不锈钢连接技术研究现状和发展趋势,分析了钛及其合金与不锈钢连接的特点以及目前存在的问题,比较了各种连接方法的优缺点,重点论述了钎焊和扩散焊方法.     

CrAISiN涂层与不同材料配副时的摩擦学特性

目的 研究CrAlSiN涂层分别与304不锈钢、TC4钛合金、Al2O3陶瓷和GCr15钢四种不同材料配副时的摩擦学特性.方法 采用阴极电弧离子镀技术在M35高速钢上制备了CrAlSiN涂层,采用扫描电镜(SEM)、显微硬度计、划痕仪、球-盘式摩擦磨损试验仪和3D轮廓仪分别测试了涂层的结构和性能.结果 CrAlSiN涂层与304不锈钢、TC4钛合金和GCr15钢配副时的磨损形式为粘着磨损和磨粒磨损,其中与亲和性高的304不锈钢、TC4钛合金粘着磨损严重.CrAlSiN涂层与不锈钢对磨时,摩擦系数最高,达到0.71;与GCr15钢对磨时,摩擦系数最低,但摩擦系数波动大;与钛合金对磨时,摩擦系数介于两者之间.CrAlSiN涂层与亲和性较差的Al2O3陶瓷之间的磨损形式为磨粒磨损,随着磨损的进行,摩擦系数逐渐降低.结论 CrAlSiN涂层与亲和性较高的材料对磨时,磨损形式为粘着磨损和磨粒磨损,与亲和性较差的Al2O3对磨时为磨粒磨损.     

难加工材料的珩磨加工技术研究

本文着重针对钛合金、高温合金以及不锈钢这三种典型的难加工材料,在深孔珩磨加工中所出现的问题进行了分析,并针对这几种材料在珩磨油石磨料类型的选取、提高珩磨效率以及选择合理的珩磨工艺措施等方面进行了试验及分析研究。研究结果表明:对于钛合金材料,采用GC(70%)和SA(30%)的混合磨料油石,磨削效率较高,油石黏附较少,并且不易破碎,具有良好的磨削效果;对于奥氏体不锈钢(1Cr18Ni9Ti),选用WA(90%)和GC(10%)的混合磨料油石,既能提高磨削比,又能减小油石的黏附现象;对于高温合金,可采用混合磨料油石(GC 70%、SA30%)进行粗珩加工,以提高珩磨效率,而采用立方氮化鹏(cBN)油石可以取得较好的珩磨加工质量。     

The corrosion behavior of stainless steels and copper alloys exposed to natural seawater

The corrosion behavior of stainless steels, titanium and copper alloys exposed to flowing Pacific Ocean water was characterized using surface analytical and electrochemical techniques. Biofilm formation on stainless steels and titanium resulted in thin films of bacteria and diatoms that did not cause significant changes of the corrosion potential (E_corr) or surface properties. Rotating cylinder experiments indicated that both E_corr and corrosion rates for stainless steels and titanium were independent of mass transport. Four surface layers were identified on copper-containing materials: substratum metal; an inorganic chloride corrosion layer that contained alloying elements; a biofilm; and crystalline, spherical phosphate-rich deposits. All copper surfaces were colonized by bacteria independent of alloy composition. The complexity of the impedance spectra for copper-containing materials was attributed to formation of surface layers and contributions of charge transfer and mass transport controlled reactions mediated by the layers. Both anodic and cathodic reactions for copper-based materials were affected by mass transport.     

Effect of activating fluxes on weld mechanical properties in TIG welding

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镁合金表面可降解聚合物改性涂层研发及应用

相比于钛合金、不锈钢、钴基合金等传统生物医用金属材料,镁合金不仅具有生物可降解特性,而且其弹性模量与人体骨骼很接近,不容易产生“应力屏蔽”,被誉为“新一代先进生物材料”。但镁合金在人体降解速率过快,由此产生的力学失稳和过量降解产物在体内的代谢吸收隐患限制了其在外科植介入医疗领域的大量推广应用。而可生物降解或可吸收的天然和合成高分子(聚合物)是全球量大面广的一类质轻、多功效、生物安全性好的生物医用材料,若将其作为可降解镁合金表面的特种防护涂层并解决好两者表界面之间的生物功能性和力学相容性,将是开发先进镁合金材料及其应用的重要发展方向。本文综述了生物可降解的镁基合金表面天然及合成高分子涂层的最新研究进展,并对其未来的研发及应用发展趋势提出展望。     

钛生物医学材料耐蚀性能研究进展

综述了钛生物医学材料在体液中的耐蚀性能.主要阐述了局部腐蚀、磨损腐蚀、腐蚀疲劳和应力腐蚀破裂等4种腐蚀形式.进而展望了目前钛生物材料的研究动向及应用前景.     

新一代焊接工艺设计专家系统

结合以往工作，针对目前焊接工艺设计专家系统存在的问题，重新进行了焊接工艺设计专家系统的设计。首先进行了广泛的知识获取，可以进行碳钢、合金钢、不锈钢、铝合金、钛合金及铜合金等各种材料的焊接工艺设计。其次、不仅可以进行单一焊接方法的工艺设计，而且可以进行组合焊接方法的工艺设计。同时，提供了方便的知识库维护方法，用户可以不断更新知识库，满足新的需要。     

上海石化海水用材的回顾与思考

介绍了上海石化海水凝汽器与冷却器及泵等的腐蚀与防护情况，并对铜合金，钛与不锈钢等用材及防腐蚀措施作了探讨与评述。