钛合金微动磨损的研究进展

钛合金耐磨性能较差，对微动磨损十分敏感，使其应用和发展受到了一定的限制。为此，总结了钛合金微动磨损性能的影响因素，综述了钛合金抗微动损伤方法的研究进展。目前，关于钛合金微动磨损的研究主要存在两方面的局限性：(1)对于钛合金微动磨损的研究大多是在单一影响因素及稳定参数下进行的；(2)缺乏关于钛合金在特殊工况下微动磨损的研究。因此，未来对于钛合金微动磨损的研究应多结合工业应用中微动磨损的失效实例，加强多因素、变参数以及特殊工况下的微动磨损研究；在掌握微动磨损失效机理的基础上，根据钛合金的特性，探索新型表面处理技术，进一步改善钛合金微动磨损失效问题。     

Ti6Al7Nb合金氮离子注入层在小牛血清溶液中的扭动微动摩擦磨损性能

利用高能离子注入及增强沉积系统对Ti6Al7Nb合金做了不同剂量的氮离子注入处理,采用球/平面接触模式,对Ti6Al7Nb合金及其离子注入层/ Zr2O球（直径为25.2 mm）接触副在小牛血清介质条件下进行了扭动微动磨损实验研究。结合动力学分析,借助X射线衍射仪（XRD）、三维形貌仪（3D-profiler）和扫描电镜（SEM）分析了测试材料成分及其扭动微动磨损磨痕形貌和微观组织结构, 探讨了Ti6Al7Nb合金及其离子注入层的扭动微动运行行为和损伤机制。结果表明：N+离子注入在钛合金表面形成了氮化钛层,使钛合金表面的微观硬度明显提高,随着注入剂量的增加,钛合金的硬度逐渐升高,磨痕逐渐变小,磨粒逐渐变细,其抗扭动微动磨损性能也提高     

DLC薄膜对TC4钛合金微动磨损行为的影响

目的 为提高TC4钛合金的抗微动磨损性能,对比研究类金刚石薄膜(DLC)和TC4钛合金在干摩擦条件下的微动磨损行为,揭示DLC薄膜抗微动磨损的机理.方法 在TC4钛合金基体上利用非平衡磁控溅射技术制备DLC薄膜.利用原子力显微镜、拉曼光谱和纳米压痕仪分析薄膜的表面形貌、物相组成以及纳米硬度.利用球/平面接触形式SRV-...     

钛合金表面离子束增强沉积MoS2基膜层及其性能

将离子束增强沉积（IBED）技术与离子束溅射的沉积技术相结合,在钛合金表面制备了MoS2,MoS2-Ti复合膜。研究了膜层的形态、结构、膜基结合强度、硬度、摩擦学性能及抗微动（fretting）损伤性能。结果表明;所获膜层较纯溅射膜结合强度高、致密性好,复合膜中允许的金属元素含量大。通过恰当地控制复合膜中Ti的含量,可获得以（002）基面择优取向的MoS2-Ti复合膜,该膜层有较好的减摩和抗磨综合性能,能够显著地改善钛合金的常规磨损、微动摩员（FW)和微动疲劳（FF）性能,特别是在磨损严重的大位移整体滑条件下,MoS2-Ti复合膜对钛合金FF抗力的提高作用可大于喷丸形变强化处理。     

离子辅助沉积TiN/Ti复合膜提高TC17钛合金高温微动疲劳抗力

为提高钛合金高温微动疲劳抗力,利用离子辅助电弧沉积技术在TC17钛合金表面制各了TiN/Ti复合膜层,研究了膜层的剖面成分分布、膜基结合强度、膜层显微硬度、韧性、常规摩擦学性能以及抗高温微动疲劳性能.结果表明:利用离子辅助电弧沉积技术可以获得硬度高、韧性好、膜基结合强度和承载能力优异的TiN/Ti复合膜层,该膜层具有良好的抗磨和减摩性能,能够显著地提高TC17钛合金在350℃高温环境下的常规磨损和微动疲劳抗力.然而,TC17钛合金表面喷丸强化后进行离子辅助沉积TiN/Ti复合膜,由于喷丸层残余压应力的显著松弛以及膜层易于开裂和脱落的缘故,微动疲劳抗力则不及喷丸强化或TiN/Ti复合膜单独作用.     

TC21钛合金表面处理技术的研究现状

介绍了TC21钛合金的表面处理技术,综述了阳极化处理技术、MAO、渗铬、渗碳、渗硼等耐磨技术以及喷丸处理技术和提高微动磨损性能的超音速火焰喷涂技术,展望了TC21钛合金表面处理技术的发展.     

钛合金空蚀损伤及防护的研究进展

钛合金具有密度小、比强度高、耐蚀性好等优势,被广泛应用于诸多工程领域。由于钛合金存在表面硬度低、耐磨性差等缺点,导致其在过流部件中容易发生空蚀损伤,会降低钛合金构件的使用寿命,因此针对钛合金空蚀损伤行为及其防护措施的研究显得极为重要。概述了空蚀现象的作用机理和理论模型,详细介绍了材料自身的力学性能、表面状态、介质类型和溶液温度等对钛合金空蚀行为的影响,着重讨论了针对钛合金空蚀损伤的多种应对措施,如热处理、激光纹理加工、激光气体氮化、化学热处理、离子注入、添加缓蚀剂等技术,总结了相应方法提高钛合金抗空蚀性能的具体原因。其中,热处理技术通过改变钛合金自身的显微组织来提高其抗空蚀性能;激光气体氮化工艺可在钛合金表面形成硬质TiN相,以抵御空泡溃灭时的冲击;化学热处理技术在钛合金表面生成了致密的陶瓷层+固溶扩散层,缓解了空泡的溃灭能,延长了空蚀的孕育期;离子注入技术依靠注入离子在钛合金材料表面产生固溶强化、位错增值强化等效果,降低其空蚀损伤。最后对钛合金空蚀及防护研究的发展方向提出了展望。     

等离子渗氮与喷丸强化复合改进钛合金抗微动损伤性能

利用直流脉冲等离子电源装置对Ti6A14V钛合金表面渗氮处理,研究了渗氮层的相组成、硬度分布、韧度及摩擦学性能,采用喷丸形变强化(SP)对渗氮层进行后处理,以达到联合提高钛合金微动疲劳(FF)抗力的目的.研究结果表明:脉冲电源等离子技术可在钛合金表面获得由TiN、Ti2N、Ti2A1N等相组成的渗氮层,该改性层能够显著地提高钛合金常规磨损和微动磨损(FW)抗力,但降低了基材的FF抗力.渗氮层的减摩和抗磨性能与SP引入的表面残余压应力协同作用,使钛合金FF抗力超过了SP单独作用.提高渗氮层韧度对改善钛合金FF和FW性能均十分重要.     

激光淬火对钛合金TC11微动磨损性能的影响

研究了激光淬火对钛合金TC11微动磨损性能的影响。结果表明：在不同微动幅度和法向载荷作用下,钛合金TC11激光淬火后抗微动磨损能力均有所提高,提高幅度与微动幅度大小和法向载荷高低有关。钛合金TC11激光淬火后微动磨损性能的改善是组织细化、表面硬度提高的结果。     

钛合金的激光表面处理研究进展

介绍了钛合金的各种激光表面改性技术及其研究进展,讨论了激光表面改性处理工艺参数对钛合金性能的影响。并介绍了其应用前景。利用激光表面处理可克服钛合金硬度低、易发生粘着磨损等缺点,同时可提高其耐蚀性及抗高温氧化等性能。此外,利用脉冲激光沉积技术在改善钛合金的生物活性等方面也取得了好的结果。     

Effect of TiN/Ti multilayer on fretting fatigue resistance of Ti-811 alloy at elevated temperature

The TiN/Ti multilayer was deposited on Ti-811 alloy surface by magnetron sputtering(MS) technique for improving fretting fatigue(FF) resistance of the titanium alloy at elevated temperature. The element distribution, bonding strength, micro-hardness and ductility of the TiN/Ti multilayer were measured. The effects of the TiN/Ti multilayer on the tribological property and fretting fatigue resistance of the titanium alloy substrate at elevated temperature were compared. The results indicate that by MS technique a TiN/Ti multilayer with high hardness, good ductility and high bearing load capability can be prepared. The MS TiN/Ti multilayer, for its good toughness and tribological behavior, can significantly improve the wear resistance and FF resistance of the Ti-811 alloy at 350 ℃.     

Influence of surface coating on Ti811 alloy resistance to fretting fatigue at elevated temperature

An extensive study of the composition distribution, bonding strength, hardness, and wear resistance of a 0Cr18Ni9 film deposited on a Ti811 titanium alloy surface by ion beam enhanced deposition (IBED) is presented. Shot peening was introduced to post-treat the modified surface to synergistically improve the fretting fatigue resistance of the Ti811 alloy at 350～C. The results indicate that the 0Cr18Ni9 film with high density, small grain size, low void radio, and high bonding strength can be prepared using IBED. As a result, the hardness, wear resistance, and fretting fatigue resistance of the Ti811 alloy are increased to a remarkable extent. Compared with shot peening treatment or IBED 0Cr18Ni9 film alone, the Ti811 titanium alloy with an IBED 0Cr18Ni9 film combined with shot peening shows a higher fretting fatigue resistance at 350℃. This is due to the synergistic effect of the high wear resistance of the film surface and the residual compressive stress induced by shot peening.     

TC4钛合金的微动疲劳行为研究

研究了TC4钛合金在柱面-平面接触条件下的微动疲劳行为.通过观察微动区的磨损特征和截面形貌,分析了微动疲劳损伤机制,探讨了磨屑的形成与演变过程及其对微动疲劳行为的影响,考察了摩擦系数随时间的变化.结果表明,TC4钛合金微动区的损伤机制以粘着磨损、磨粒磨损和接触疲劳为主,并伴有氧化磨损.磨屑是基体材料脱落、破碎、氧化形成的,磨屑中的硬质氧化物颗粒促进了合金表面的磨粒磨损,加速了疲劳失效.     

Effect of TiN/Ti composite coating and shot peening on fretting fatigue behavior of TC17 alloy at 350 °C

A TiN/Ti composite coating has been prepared on a TC17 titanium alloy substrate by an ion-assisted arc deposition (IAAD) technique with a view to improving the fretting fatigue resistance of the titanium alloy at 350 °C. The composition distribution, bonding strength, micro-hardness, ductility, tribological properties, and fretting fatigue resistance at elevated temperature of the coating have been investigated. The results indicate that the IAAD technique can be used to prepare a TiN/Ti composite coating with high hardness, good ductility, excellent bonding strength, and high load-bearing capability. The TiN/Ti composite coatings can improve the resistance to wear and fretting fatigue of the Ti alloy, as manifested in its excellent tribological behavior at 350 °C. However, the fretting fatigue resistance of the titanium alloy treated by shot peening (SP) combined with IAAD TiN/Ti coating post-treatment was lower than that by IAAD TiN/Ti coating or SP alone, because the compressive residual stress induced by SP was significantly relaxed during coating process and the coating easily cracked and broke off.     

The effect of surface modification on fretting fatigue in Ti Alloy turbine components

Severe fretting damage has been observed on the pressure surfaces of fan and compressor blade dovetails/disks in an aerospace gas turbine engine. A study has been carried out to evaluate the effect of an ion implantation technique in combination with the presently used surface treatments, such as shot peening and coating, on the fretting fatigue life of titanium alloy gas turbine engine components. The results from fretting fatigue tests, residual stress measurements, and nanoindentation tests were used to quantitatively evaluate the effect of various surface treatments on the fretting fatigue life of the fan blade and disk materials. Results from microstructural characterization and analyses of elemental and phase distributions within the implanted region are used to understand the effect of ion implantation on the surface properties of the alloys. Finally, an attempt has been made to evaluate the potential for improving the fretting fatigue life of the engine components using various surface modification techniques.     

Cu/Ni多层膜对Ti811合金微动磨损和微动疲劳抗力的影响

在Ti811钛合金表面利用离子辅助磁控溅射沉积技术制备20～1200nm不同调制周期的Cu/Ni金属多层膜,分析多层膜的结构,测试膜基结合强度、膜层显微硬度和韧性,对比研究不同调制周期的Cu/Ni多层膜对钛合金基材常温下微动磨损性能和微动疲劳(FF)抗力的影响。结果表明:利用离子辅助磁控溅射技术可以获得致密度高、晶粒细化、膜基结合强度高的Cu/Ni多层膜,该类多层膜具有良好的减摩润滑作用,因而改善了Ti811钛合金常温下抗微动磨损和微动疲劳性能;Cu/Ni多层膜对钛合金FF抗力的改善程度随膜层调制周期呈现非单调变化趋势,调制周期为200nm的Cu/Ni多层膜对钛合金FF抗力的提高程度最大,原因归于该膜层具有良好的强韧和润滑综合性能。     

钛合金自冲铆接头微动磨损机理及疲劳性能

对钛合金同种TA1-TA1（TT）及异种TA1-Al5052（TA）,TA1-H62（TH）自冲铆接头进行疲劳试验,用扫描电子显微镜对断口及微动区进行观测研究其微动磨损机理,并研究下板强度对接头疲劳寿命和失效形式的影响.结果表明,断口裂纹萌生区即为微动磨损区.微动磨损导致微动区亚表面产生微裂纹并逐步扩展为宏观疲劳裂纹导致接头最终失效;微动磨屑在微动磨损过程中主要起减轻磨损作用.总体上TT接头具有最优疲劳性能,疲劳载荷较高时TA接头疲劳性能优异,疲劳载荷较低时TH接头疲劳性能优异.两板强度相当且疲劳载荷较高时失效形式主要为铆钉断裂,疲劳载荷较低时失效形式主要为下板断裂;而下板强度与上板强度相差较大时,疲劳失效形式为下板断裂.