钛表面激光熔覆原位制备Ti5Si3涂层结构及摩擦学性能

引用本文

郭纯, 周健松, 陈建敏. 钛表面激光熔覆原位制备Ti₅Si₃涂层结构及摩擦学性能 . 无机材料学报, 2012, 27(9): 970-976
GUO Chun, ZHOU Jian-Song, CHEN Jian-Min. Microstructure and Tribological Properties of Ti₅Si₃CoatingIn-situSynthesized on Titanium Substrate by Laser Cladding . Journal of Inorganic Materials, 2012, 27(9): 970-976 复制到剪切板

Permissions

This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

钛表面激光熔覆原位制备Ti₅Si₃涂层结构及摩擦学性能

郭纯^1,², 周健松¹, 陈建敏¹

1. 中国科学院兰州化学物理研究所, 兰州 730000

2. 中国科学院研究生院, 北京100039

陈建敏, 研究员. E-mail:chenjm@lzb.ac.cn

郭纯(1984-), 男, 博士研究生. E-mail:guochun@licp.cas.cn

基金:国家自然科学基金重点项目(51045004); 中科院知识创新工程重要方向项目(YYYJ-0913);

摘要

利用激光熔覆技术在钛表面预置硅粉原位制备了Ti₅Si₃涂层. 用XRD、SEM和TEM分析了涂层的组成和组织结构. 在UMT摩擦磨损试验机上对Ti₅Si₃涂层在不同载荷和不同滑动速度下的摩擦磨损性能进行了测试. 实验结果表明: 涂层的物相主要是Ti₅Si₃相和基材Ti相, 涂层的显微结构为球状和块状晶, Ti₅Si₃涂层具有较高的显微硬度, 涂层截面的平均显微硬度约为840 HV_0.2, 是钛基材的4.4倍; Ti₅Si₃涂层可显著提高钛基材的耐磨性能; Ti₅Si₃涂层的磨损机理为磨粒磨损和粘着磨损.

关键词: 钛; 激光熔覆; 涂层; Ti₅Si₃; 摩擦性能

中图分类号:TG115 文献标志码:A 文章编号:1000-324X(2012)09-0970-07

Microstructure and Tribological Properties of Ti₅Si₃CoatingIn-situSynthesized on Titanium Substrate by Laser Cladding

GUO Chun^1,², ZHOU Jian-Song¹, CHEN Jian-Min¹

1. Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China

2. Graduate University of the Chinese Academy of Sciences, Beijing 100039, China

Fund:National Natural Science Foundation of China (51045004); Knowledge Innovation Project in Chinese Academy of Science (YYYJ-0913);

Abstract

Using silicon powder as the precursor to improve the wear resistance of Ti₅Si₃ coating wasin situ successfully synthesized on Ti substrate by laser cladding. Friction and wear behavior of Ti₅Si₃ coatings under different normal loads and sliding speeds wear test conditions were evaluated using a UMT-2MT friction and wear tester. It is found that the prepared coating is mainly composed of Ti₅Si₃ and Ti phases. The high resolution transmission electron microscopy results confirm further the existence of Ti₅Si₃ compound in the prepared coating. Ti₅Si₃ coating has spherical and block-like microstructure. The Ti₅Si₃ coating shows a high average hardness of approximately 840 HV_0.2, which is about 4.4 times as that of Ti substrate. Tribological properties of the prepared Ti₅Si₃ coating were systematically evaluated. It is found that the Ti₅Si₃ coating can improve the wear resistance of Ti. The wear mechanism of Ti₅Si₃ coating is abrasive and adhesive wear when sliding against GCr15 steel ball under all wear conditions.

Keyword: titanium; laser cladding; coating; Ti₅Si₃; tribological property

Show Figures

钛及钛合金具有密度小、比强度高、生物相容性好、耐腐蚀性强等优点, 被广泛应用于航海、航空、航天、冶金、石油化工、医学、体育等领域^{[ 1, 2, 3, 4]}. 但钛合金表面硬度低、耐磨性差、抗高温氧化性能差等, 限制了其在摩擦工况下的广泛应用^{[ 5, 6]}.

表面改性是提高钛合金摩擦学性能的有效手段. 钛及钛合金的表面改性技术主要有: 激光表面处理、气相沉积、电火花沉积、脉冲激光沉积、电泳沉积、离子渗碳渗氮、微弧氧化、热喷涂、表面金属镀层(化学镀、电镀)等等^{[ 7, 8, 9, 10, 11]}. 激光表面处理技术具有能量密度高, 加工速度快、可对零件进行选区加工、热影响区小、稀释率低、工件热变形小等优点, 主要包括激光表面合金化、激光熔覆、激光淬火(激光相变硬化、激光重熔)等^{[ 12]}. 国内外对钛及钛合金的激光表面改性进行了大量的研究, 主要集中于钛及钛合金的激光表面硼化、氮化、复合合金化、激光熔覆镍、钴、铁基涂层和钛铝金属间化合物涂层^{[ 13, 14, 15]}.

硅化物(Ti₅Si₃)具有低密度(4.63 g/cm³)、高熔点(2043 K)以及良好的抗高温氧化和高温稳定性等优点, 具有高温工程应用的前景^{[ 16, 17, 18]}. 文献[19-21]报道了在钛铝合金表面通过激光熔覆原位制备含Ti₅Si₃的涂层, 但是在钛表面原位制备Ti₅Si₃涂层以提高钛耐磨性能的研究却鲜有报道.

本工作在钛表面预置硅粉进行激光熔覆处理, 对熔覆层的组成、组织结构及摩擦磨损性能进行较系统的研究, 为钛表面激光熔覆Ti₅Si₃涂层技术的工程应用提供依据.

1 实验

基材选用试样尺寸为φ30 mm×12 mm的钛(TA1),其化学成分(wt%)为: Fe≤0.2, Si≤0.1, C≤0.08, N≤0.03, H≤0.015, O≤0.18, Ti 余量. 为了提高基材表面的激光吸收率, 在激光熔覆处理前先对钛基材表面进行喷砂、丙酮超声处理, 并在钛表面预置硅粉(纯度≥99wt%, 杂质Fe、Cu、Sb总计≤1.00%, 粒径74 μm)厚度约为0.5 mm; 然后用10 kW的横流CO₂激光加工成套设备(DL-HL- T10000B)对基材表面进行激光熔覆处理. 激光熔覆的参数为激光功率2 kW, 扫描速度 600 mm/min, 光斑尺寸φ3 mm, 聚焦距离103 mm, 搭接率50%. 为了避免裂纹的产生, 激光熔覆前用电炉预热试样, 预热温度 300℃.

用MH-5-VM显微硬度仪测截面的显微硬度, 毎个深度点测量5次取平均值. 用JSM-5600LV型扫描电镜(SEM)观察熔覆层的截面形貌, 用D/Max-2400 X-ray Diffractometer (XRD)检测合金化层的组成. 涂层的晶体结构用 FEI Tecnai-G²-F30型透射电镜(TEM)进行表征, 加速电压300 kV. 用UMT-2MT摩擦磨损试验机对制备的熔覆层进行摩擦磨损性能测试, 样块尺寸为 19 mm×19 mm× 12 mm, 摩擦对偶为φ6 mm的GCr15不锈钢球. 测试条件载荷5~15 N, 振幅5 mm, 滑动距离180 m, 滑动速度(0.025~0.2)m/s. 磨损体积损失用Micro-XAM 3D non-contract surface mapping profiler表面形貌仪进行测量. 毎个样品在相同测试条件下重复三次, 摩擦因数和磨损体积均为三次结果的平均值. 用SEM观察磨损后磨痕的表面形貌. 为了对比Ti₅Si₃涂层的耐磨性能, 文中引用了钛在相同测试条件下的磨损体积^{[ 22]}.

2 结果与讨论

2.1 涂层的组成与结构

图1为激光熔覆制备涂层的XRD图谱, 从图中可以看出涂层主要含Ti₅Si₃和Ti 相. 经过激光熔覆处理的硅粉和基材钛反应生成了Ti₅Si₃相. 激光束具有较高的能量密度, 可以在极短的时间内使材料表面达到较高的温度. 根据文献报道, 激光表面处理过程中, 材料表面激光束照射处的温度可以用公式(1)进行估算^{[ 23, 24]}:

(1)

其中 P为激光功率(为W), η为材料对激光的吸收率. r为激光束的光斑半径(为m), λ为材料的热导率(W/(m∙K)), ν 为扫描速度(m/s)和α为热扩散系数(m²/s). 在本文中钛对波长10.6 μm 的激光的吸收率约30%, 钛的热扩散系数为 5.97×10^-6m²/s, 钛的热导率为18 W/(m∙K)^{[ 23, 25]}. 激光束半径为0.0015 m, 扫描速度0.01 m/s, 激光功率2000 W. 把上述参数带入公式, 可估算出激光束照射处的材料表面温度约为3825 K. 另外, 结合钛和硅反应的吉布斯自由能图(图2, FACT软件计算, 可以看出钛和硅反应的吉布斯自由能为很大的负值, 因此从热力学角度来看, 钛和硅很容易反应生成Ti₅Si₃相.

	Figure Option View Download New Window
	图1 涂层的XRD图谱Fig. 1 XRD pattern of the laser cladding coating

	Figure Option View Download New Window
	图2 钛和硅反应的吉布斯自由能曲线Fig. 2 Changes of Gibbs energy for possible reactions of 5Ti+ 3Si=Ti₅Si₃ as functions of temperature

图3是Ti₅Si₃涂层截面的SEM照片, 从图中可看出涂层的界面处有明显的激光熔池的“月牙”形貌, 在多道搭接扫描模式下呈涟漪状. 涂层与基材之间呈现良好结合, 看不出明显的分界面, 涂层质量较好, 没有裂纹, 在靠近表面处有少量气孔, 涂层厚度约1.0 mm.

	Figure Option View Download New Window
	图3 涂层的截面形貌Fig. 3 Cross-section morphology of the laser cladding coating

图4给出了Ti₅Si₃涂层的TEM照片和相应的选区电子衍射图案(SAED). 从图4可以看出, Ti₅Si₃涂层晶体结构为块状和近球状的晶粒, 并且出现了纳米级晶粒. SAED分析表明生成的是Ti₅Si₃相. 另外,纳米级晶粒的形成可归因于激光熔覆是一个快速加热、快速冷却的过程, 冷却速度可达到10⁶℃/s^{[ 26]}, 在如此高的冷却速度下, 使凝固组织细化.

	Figure Option View Download New Window
	图4 涂层的TEM照片和选区电子衍射分析Fig. 4 TEM micrograph and the corresponding SAED pattern of the laser cladding coating

2.2 涂层的截面硬度

图5所示为Ti₅Si₃涂层的截面显微硬度曲线, 可以看出涂火层的平均厚度为1.0 mm, 与SEM 测出的涂层厚度值相符. Ti₅Si₃涂层截面的平均显微硬度约为840 HV_0.2, 是钛基材的4.4倍(钛的显微硬度约190 HV_0.2), 说明Ti₅Si₃涂层硬度较高. 涂层和钛基材之间存在明显的界面, 在界面处20~50 μm涂层的硬度从846 HV_0.2陡然降到252 HV_0.2,接近基材硬度. 界面处基材的显微硬度高于钛基材的原始显微硬度, 这是由于为涂/基界面处的基材在激光熔覆过程中表面层受熔池的热影响发生了相变硬化, 从而提高了硬度.

	Figure Option View Download New Window
	图5 涂层的截面硬度Fig. 5 Microhardness profile of the laser cladding coating

2.3 涂层的摩擦磨损性能

2.3.1 载荷对涂层摩擦磨损性能的影响

图6和图7分别是Ti₅Si₃涂层的摩擦因数和磨损体积随载荷变化的曲线(同时为了对比给出了钛的磨损体积随载荷的变化). 从图6可以看到Ti₅Si₃涂层的摩擦因数受载荷的影响显著, 即摩擦因数都随载荷的增加先增大后减小, 根据摩擦学原理, 这一现象可以用公式(2)进行解释^{[ 27, 28]}:

(2)

其中 μ为摩擦因数, S为剪切应力, A为接触面积, W为载荷.

	Figure Option View Download New Window
	图6 涂层摩擦因数随载荷变化关系曲线Fig. 6 Variation of friction coefficient of the laser cladding coating as a function of normal load at sliding speed of 0.1 m/s

	Figure Option View Download New Window
	图7 涂层和基材钛磨损体积随载荷变化关系曲线Fig. 7 Variation of wear volumes of the laser cladding coating and Ti substrate as a function of normal load at sliding speed of 0.1 m/s

根据公式(2), 在摩擦磨损过程中, Ti₅Si₃涂层与GCr15不锈钢球对磨时摩擦因数随载荷的增加而增大, 是因为增加载荷摩擦副之间的剪切力增加, 同时接触面积也增加, 且两者增加的比例乘积大于载荷增加的比例, 所以根据公式摩擦因数增加. 当载荷增加到一定值以后, 剪切力和接触面积增加的比例减小, 导致载荷增加速度大于接触面积和剪切力增加的比例乘积, 所以摩擦因数随载荷的增加反而减小. 从磨损的体积损失随载荷变化的曲线(图 7)可以看出, Ti₅Si₃涂层和钛的磨损体积均随载荷的增加而增加, 这与阿查德磨损定理相一致^{[ 29]}. 从图7 还可看出Ti₅Si₃涂层与钛基材相比, 磨损体积较小(钛基材的磨损体积约是Ti₅Si₃涂层的2倍), 说明Ti₅Si₃涂层相对于钛基材具有较好的耐磨性能, 可见激光熔覆Ti₅Si₃涂层可以提高钛的耐磨性能, 这可归因于激光Ti₅Si₃涂层相对于钛基材有较高的表面硬度, 根据阿查德磨损定理^{[ 29]}可知, 提高硬度有利于提高材料的耐磨性能.

图8是不同载荷下的Ti₅Si₃涂层磨损形貌, 从图8可以看出, 在5和15 N载荷下, Ti₅Si₃涂层磨损表面均存在很明显的犁沟和因粘着而产生的剥落坑, 说明Ti₅Si₃涂层的磨损机理为磨粒磨损和粘着磨损. 摩擦磨损是一个系统体系, 为了更进一步理解磨损机理, 图9给出了对偶不锈钢球磨损表面的形貌图及相应的Fe和Ti的面分布图. 从图9可以看出对偶GCr15不锈钢球表面有轻微的犁沟和明显的粘着产生的凸起, EDS面分布结果显示这些粘着凸起含Ti, 说明摩擦过程中发生了涂层成分向对偶的转移, 进一步证实了粘着磨损的存在, 这一结果与图8得出的结果相一致.

	Figure Option View Download New Window
	图8 涂层在不同载荷下磨损形貌的SEM照片Fig. 8 Typical worn morphologies of the laser cladding coating at different normal loads(a) 5 N; (b) 15 N

	Figure Option View Download New Window
	图9 对偶GCr15在不同载荷下磨损表面形貌和元素面分布图Fig. 9 SEM micrographs and the corresponding EDS element surface distribution of the worn surface of the counterbody GCr15 steel ball(a) Normal load 5 N; (b) Normal load 15 N (sliding speed of 0.1 m/s)

2.3.2 滑动速度对涂层摩擦磨损性能的影响

图10是在10 N的载荷下, Ti₅Si₃涂层与GCr15不锈钢球对磨时摩擦因数与滑动速度的关系曲线, 可以看出Ti₅Si₃涂层与GCr15不锈钢球对磨时摩擦因数随滑动速度的增大而减小. 在干摩擦条件下, 随着滑动速度的增加, 摩擦对偶之间的剪切和犁沟产生的摩擦热增加, 摩擦界面处的温度升高, 从而降低了接触面的硬度. 此外, 摩擦表面可能生成氧化物或转移膜, 导致摩擦对偶之间的作用力减弱, 最终导致摩擦系数的减小^{[ 30]}. 从图11可以看出Ti₅Si₃涂层的磨损体积要远小于在相同摩擦测试条件下钛的磨损体积, 说明在不同滑动速度下Ti₅Si₃涂层与钛相比有更好的耐磨性能. 但是Ti₅Si₃涂层和钛的磨损体积随滑动速度变化呈现出不同的变化趋势, 即钛的磨损体积随滑动速度的增加而减小, 而Ti₅Si₃涂层的磨损体积随滑动速度的增加而增加. Ti₅Si₃金属间化合物室温脆性较大, 在摩擦过程中增加滑动速度, Ti₅Si₃涂层表面受到的赫兹接触应力增加, 从而导致Ti₅Si₃涂层的磨损体积随滑动速度的增加而增大.

	Figure Option View Download New Window
	图10 涂层摩擦因数随滑动速度变化关系曲线Fig. 10 Variation of friction coefficient of the laser cladding coating as a function of sliding speed at normal load of 10 N

	Figure Option View Download New Window
	图 11 涂层和基材钛在载荷10 N时磨损体积与滑动速度的关系曲线Fig. 11 Variation of wear volumes of the laser cladding coating and Ti substrate as a function of sliding speed at normal load of 10 N

图12是激光熔覆Ti₅Si₃涂层, 在干摩擦测试条件下, 滑动速度分别为0.025和0.2 m/s与GCr15不锈钢球对磨后磨损表面的SEM照片(载荷10 N). 从图12可以看出, Ti₅Si₃涂层在不同滑动速度下的磨损表面与在不同载荷下的磨损表面相类似, 即均存在很明显的犁沟和因粘着而产生的剥落坑, 说明Ti₅Si₃涂层在不同滑动速度下的磨损机理为磨粒磨损和粘着磨损. 同样为了更进一步研究Ti₅Si₃涂层在不同滑动速度下的磨损机理, 图13给出了对偶不锈钢球磨损表面的形貌图及相应的Fe 和Ti的面分布图. 可以看出对偶GCr15不锈钢球表面有犁沟和粘着产生的凸起(主要含Ti), 证明了摩擦过程中发生了粘着磨损. 与不同载荷下得出的结果相近.

	Figure Option View Download New Window
	图12 涂层在不同滑动速度下磨损形貌的SEM照片Fig. 12 Typical worn morphologies of the laser cladding coating at different sliding speeds(a) 0.025 m/s; (b) 0.2 m/s

	Figure Option View Download New Window
	图13 对偶GCr15在不同滑动速度下磨损表面形貌和元素面分布图Fig. 13 SEM micrographs and the corresponding EDS element surface distribution of the worn surface of the counterbody GCr15 steel ball(a) Sliding speed 0.025 m/s; (b) Sliding speed 0.2 m/s (normal load of 10 N)

2.3.3 磨屑形貌

为了更进一步理解磨损机理, 图14给出了Ti₅Si₃涂层在载荷15 N、滑动速度0.1 m/s和载荷10 N、滑动速度0.025 m/s摩擦测试条件下的磨屑形貌, 从图可以看出, Ti₅Si₃涂层在两个测试条件下的磨屑具有相似的形貌, 即块状和近球状. 而且两个测试条件下的磨屑的尺寸都很小(小于5 μm). 根据摩擦学理论, 一般认为较小尺寸的磨屑对应较温和的磨损. 另外, 产生球状的磨屑是由块状的磨屑在摩擦过程中来不及逸出磨痕经过研磨的结果^{[ 31]}.

	Figure Option View Download New Window
	图14 磨屑的形貌照片(a)载荷15 N, 滑动速度0.1 m/s;(b) 载荷10 N, 滑动速度0.025 m/sFig. 14 SEM images of wear debris of the laser cladding coating and GCr15 steel ball friction pair(a) Normal load of 15 N, sliding speed of 0.1 m/s; (b) Normal load of 10 N, sliding speed of 0.025 m/s

3 结论

1) 通过激光熔覆技术在钛表面原位制备了Ti₅Si₃涂层;

2) XRD结果表明, 熔覆后的涂层的主要成分为Ti₅Si₃相. 截面的SEM结果表明, Ti₅Si₃涂层与基材钛结合良好;

3) Ti₅Si₃涂层具有较高的显微硬度, 涂层截面的显微硬度约为840 HV_0.2, 是钛基材的4.4倍;

4) 不同载荷和不同滑动速度下的摩擦磨损测试结果显示, Ti₅Si₃涂层与钛基材相比在相同的测试条件下具有更小的磨损体积和更好的耐磨性能. Ti₅Si₃涂层在不同载荷和不同滑动速度下的磨损机理均为磨粒磨损和粘着磨损.

参考文献

View Option

[1]	Bruni S, Martinesi M, Stio M, et al. Effects of surface treatment of Ti-6Al-4V titanium alloy on biocompatibility in cultured human umbilical vein endothelial cells. Acta Biomater. , 2005, 1(2): 223-234. [本文引用:1] [JCR: 5.093]
[2]	DAS M, BALLA V K, BASU D, et al. Laser processing of SiC-particle-reinforced coating on titanium. Scr. Mater. , 2010, 63(4): 438-441. [本文引用:1] [JCR: 2.821]
[3]	LI X M, LI Y S, HAN Y. Preparation of alumina coatings on titanium by cathodic micro-arc electrodeposition. Journal of Inorganic Materials, 2005, 20(6): 1493-1499. [本文引用:1] [JCR: 0.531] [CJCR: 1.106]
[4]	GUO L T, LIU X C, GAO J Q, et al. Effect of titaniumsurface oxidation on the bonding strength of Ti-porcelain. Journal of Inorganic Materials, 2009, 24(5): 915-918. [本文引用:1] [JCR: 0.531] [CJCR: 1.106]
[5]	GUO C, ZHOU J, ZHAO J, et al. Effect of ZrB₂ on the microstructure and wear resistance of Ni-based composite coating produced on pure Ti by laser cladding. Tribol. Trans. , 2011, 54(1): 80-86. [本文引用:1]
[6]	BAKER T N, SELAMAT M S. Surface engineering of Ti-6Al-4V by nitridingand powder alloying using CW CO₂ laser. Mater. Sci. Technol. , 2008, 24(4): 189-200. [本文引用:1] [JCR: 1.198] [CJCR: 0.293]
[7]	YILDIZ F, YETIM A, ALSARAN A, et al. Plasma nitriding behavior of Ti6Al4V orthopedic alloy. Surf. Coat. Technol. , 2008, 202(11): 2471-2476. [本文引用:1] [JCR: 1.941]
[8]	JIANG P, HE X L, LI X X, et al. Wear resistance of a laser surface alloyed Ti-6Al-4V alloy. Surf. Coat. Technol. , 2000, 130: 24-28. [本文引用:1] [JCR: 1.941]
[9]	NOLAN D, HUANG S, LESKOVSEK V, et al. Sliding wear of titanium nitride thin films deposited on Ti-6Al-4V alloy by PVD and plasma nitriding processes. Surf. Coat. Technol. , 2006, 200(20/21): 5698-5705. [本文引用:1] [JCR: 1.941]
[10]	LI Q J, WU H H, WANG J B, et al. Effects of pulse frequencies on properties of MAO coatings on pure titanium. Journal of Inorganic Materials, 2006, 21(2): 488-492. [本文引用:1] [JCR: 0.531] [CJCR: 1.106]
[11]	GONG Y S, TU R, GOTO T. High-speed deposition of oriented TiN_x films by laser metal-organic chemical vapor deposition. Journal of Inorganic Materials, 2010, 25(4): 391-395. [本文引用:1] [JCR: 0.531] [CJCR: 1.106]
[12]	ZHANG S, ZHANG C H, WU W T, et al. An in situ formed TiC particle reinforcement composite coating induced by laser melting on surface of alloy Ti6Al4V and its wearing performance. Acta Metall. Sinica, 2001, 37(3): 315-320. [本文引用:1] [JCR: 0.612] [CJCR: 0.835]
[13]	GUO C, ZHOU J, ZHAO J, et al. Microstructure and friction and wear behavior of laser boronizing composite coatings on titanium substrate. Appl. Surf. Sci. , 2011, 257(9): 4398-4405. [本文引用:1] [JCR: 2.112]
[14]	GUO B, ZHOU J, ZHANG S, et al. Phase composition and tribological properties of Ti-Al coatings produced on pure Ti by laser cladding. Appl. Surf. Sci. , 2007, 253(24): 9301-9310. [本文引用:1] [JCR: 2.112]
[15]	GUO C, ZHOU J, ZHAO J, et al. Improvement of the oxidation and wear resistance of pure Ti by laser-cladding Ti₃Al coating at elevated temperature. Tribol. Lett. , 2011, 42(2): 151-159. [本文引用:1] [JCR: 1.743]
[16]	GU D D, SHEN Y F. Microstructure of in situ TiN-Ti₅Si₃ composites prepared by selective laser melting. Acta Metall Sinica, 2010, 46(6): 761-768. [本文引用:1] [JCR: 0.612] [CJCR: 0.835]
[17]	Counihan P J, Crawford A, Thadhani N N. Influence of dynamic densification on nanostructure formation in Ti₅Si₃ intermetallic alloy and its bulk properties. Mater. Sci. Eng. A, 1999, 267: 26-35. [本文引用:1]
[18]	GU D D, HAGEDORN Y C, MEINERS W, et al. Selective laser melting of in-situ TiC/Ti₅Si₃ composites with novel reinforcement architecture and elevated performance. Surf. Coat. Technol. , 2011, 205(10): 3285-3292. [本文引用:1] [JCR: 1.941]
[19]	WANG H M, LIU Y F. Microstructure and wear resistance of laser clad Ti₅Si₃/NiTi₂ intermetallic composite coating on titanium alloy. Mater. Sci. Eng. A, 2002, 338: 126-132. [本文引用:1]
[20]	LIU X, WANG H. Microstructure, wear and high-temperature oxidation resistance of laser clad Ti₅Si₃/γ/TiSi composite coatings on γ-TiAl intermetallic alloy. Surf. Coat. Technol. , 2006, 200(14/15): 4462-4470. [本文引用:1] [JCR: 1.941]
[21]	RAO K, ZHOU J. Characterization and mechanical properties of in situ synthesized Ti₅Si₃/TiAl composites. Mater. Sci. Eng. A, 2003, 356(1/2): 208-218. [本文引用:1]
[22]	GUO C, ZHOU J, ZHAO J, et al. Microstructure and tribological properties of ZrB₂-containing composite coating produced on pure Ti Substrate by laser surface alloying. J. Tribol. , 2011, 133(1): 011301-1-7. [本文引用:1] [JCR: 1.213]
[23]	Selvan J S, Subramanian K, Nath A K, et al. Laser boronising of Ti-6Al-4V as a result of laser alloying with pre-placed BN. Mater. Sci. Eng. A, 1999, 260(1/2): 178-187. [本文引用:2]
[24]	Eskin S, Zahavi J, Berner A. CO₂-Laser nitriding as a result of Ti coating modification in a nitrogen atmosphere. 1. Features of nitriding process. Laser Eng. , 1995, 4(2): 85-96. [本文引用:1] [JCR: 0.469]
[25]	YAN M, LIU B, LI J. 中国航空材料手册, 第四卷. 北京: 中国标准出版社, 2001: 8-21. [本文引用:1]
[26]	PEI Y T, OUYANG J H, LEI T Q. Developments of laer clad composite coatings. Journal of Harbin Institute of Technology, 1994, 26(1): 73-80. [本文引用:1] [CJCR: 0.1571]
[27]	BLAU P J. Metals Hand book, 10th Edition. USA: The Materials Information Society, 1990: 414-418. [本文引用:1]
[28]	LA P, XUE Q, LIU W. Effects of boron doping on tribological properties of Ni₃Al-Cr₇C₃ coatings under dry sliding. Wear, 2001, 249(1/2): 94-100. [本文引用:1] [JCR: 1.262]
[29]	ARCHARD J F. Contact and rubbing of flat surfaces. J . Appl. Phys. , 1953, 24(8): 981-988. [本文引用:2] [JCR: 0.71]
[30]	CHU C L, WU S K. A study on the dry uni-directional sliding behaviour of tiatnium aluminides. Scripta Matall Mater. , 1999, 33(1): 139-143. [本文引用:1]
[31]	BHUSHAN B. Introduction to Tribology. New York: John Wiley & Sons, 2002: 210-212. [本文引用:1]

2005

5.093

0.0

Acta Biomater.. 2005, 1(2):223-234 DOI:10.1016/j.actbio.2004.11.001

Effects of surface treatment of Ti-6Al-4V titanium alloy on biocompatibility in cultured human umbilical vein endothelial cells

Abstract

Among the titanium alloys employed as implant materials, the Ti–6Al–4V alloy is still widely used. Ti–6Al–4V titanium alloy samples, in untreated state and subjected to treatments in air by furnace or glow-discharge processes, were put in contact with human umbilical vein endothelial cells (HUVEC) in order to evaluate their effects on biocompatibility. In HUVEC kept for 48 h in the presence of the three sample types neither cell proliferation nor protein content nor lactate dehydrogenase release in the culture medium are affected, while apoptosis is induced after 48- and 96-h contact of the cells with the untreated sample type, and after 96-h contact with the plasma treated one, the furnace treated sample type being ineffective. The expression of two adhesion molecules, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) was also studied. The incubation of HUVEC with the three sample types for 48 or 96 h induces a significant increase in ICAM-1 protein levels, in comparison with control cells, while VCAM-1 expression is not detectable. In the same way, TNF-α release in the culture medium, assayed after 48- and 96-h contact of the cells with the three sample types, is significantly higher, in comparison with control, even if the highest values are registered in the presence of the untreated samples. Taken together, these data indicate that, although Ti–6Al–4V alloy samples, and in particular the treated ones, show a good biocompatibility, attention must be given to the first signs of inflammation.

... 钛及钛合金具有密度小、比强度高、生物相容性好、耐腐蚀性强等优点, 被广泛应用于航海、航空、航天、冶金、石油化工、医学、体育等领域^[1,2,3,4] ...

2010

2.821

0.0

Scr. Mater.. 2010, 63(4):438-441 DOI:10.1016/j.scriptamat.2010.04.044

Laser processing of SiC-particle-reinforced coating on titanium

Laser engineered net shaping has been used to create a Ti–SiC composite layer on Ti to improve its wear resistance. The influences of laser power and scanning speed on the microstructure and wear resistance of the coatings were examined. Laser parameters were found to have a strong influence on the dissolution of SiC, leading to the formation of Ti₅Si₃ and TiC with a high amount of SiC on the surface. The composite coatings with hardness between 976 and 1167 HV exhibited average wear rate between 5.91 and 6.60 × 10⁻⁴ mm³ (N m)⁻¹.

2005

0.531

1.106

Journal of Inorganic Materials. 2005, 20(6):1493-1499

Preparation of alumina coatings on titanium by cathodic micro-arc electrodeposition

State Key Laboratory for Mechanical Behavior of Materials; Xi an Jiaotong University; Xi an 710049, China

An alumina coating with a thickness of 100μm on a titanium substrate was prepared by cathodic micro-arc electrodeposition. The microstructures and phase compositions
of the coating at different voltages were studied, and the growth mechanism of the coating was analyzed. The results show that the coating grows by
the following steps: the stage of no electric spark, micro-arc discharge and local arc light. In these courses Al(NO₃)₃ is dissociated and Al(OH)₃
is deposited and dehydrated. The high temperature and pressure produced in micro-arc area are keys to the formation of the alumina coating. The coating
is mainly composed of γ-Al₂O₃ and α-Al₂O₃. The content of α-Al₂O₃ is increased with increasing voltage, which
amounts to 7% at 400V.

采用阴极微弧电沉积在钛表面生成了厚度达100μm的氧化铝涂层,研究了不同电压下涂层的结构和组成,分析了涂层的生长规律和形成过程.结果表明:阴极微弧电沉积过程包括火花前、微弧和局部弧光三个阶段,期间伴随有Al(NO₃)₃的离解、Al(OH)₃的沉积与高温烧结等反应,微弧区产生的高温高压是形成Al₂O₃涂层的关键.涂层主要由γ-Al₂O₃和α-Al₂O₃组成,随电压升高,α-Al₂O₃的含量逐渐增加,在400V时其含量达76%.

2009

0.531

1.106

Journal of Inorganic Materials. 2009, 24(5):915-918 DOI:10.3724/SP.J.1077.2009.00915

Effect of titaniumsurface oxidation on the bonding strength of Ti-porcelain

(1. The Material Science and Engineering Colloge, China University of Mining and Technology, Xuzhou 221116, China; 2. State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an 710049, China; 3. The Fourth Military Medical University, Xi’an 710032, China; 4. Department of Prosthodentics, Affiliated Hospital of Stomatology, School of Medicine, Zhejiang University, Hangzhou 310006, China)

Effects of titanium surface oxidation on titanium-ceramic adhesion were investigated. Cast pure titanium was subjected to pre-oxidation and introduction of an intermediate layer of SnO_x by sol-gel process. Specimen surfaces were characterized by XRD and SEM/EDS. The adhesion between the titanium and porcelain was evaluated by three-point flexure bond test. A rutile layer is formed on the titanium surface after pre-oxidation. Failure of the titanium-porcelain with pre-oxidation treatment predominantly occurs at the titanium-oxide interface. Pre-oxidation treatment does not affect the fracture mode of the titanium-porcelain system. The rutile layer is more strongly bonded to the porcelain than titanium. The poor adhesion of the rutile with substrate is due to the thermal stress arising from the large lattice mismatch and difference in coefficient of thermal expansion between Ti and rutile during cooling. However, a thin and coherent SnO_x film with small spherical pores obtained after heat-treated at 300℃ serves as an effective oxygen diffusion barrier to improve titanium-ceramic adhesion. The SnO_x films change the fracture mode of the titanium-porcelain system and improve the mechanical and chemical bonding between porcelain and titanium, resulting in the increased bonding strength of titanium-porcelain.

研究了钛表面氧化对钛/瓷结合强度的影响, 并采用溶胶凝胶技术在钛表面制备SnO_x中间层, 研究SnO_x层对钛/瓷结合强度的影响. 结果表明：空气炉中800℃氧化3min后, 钛/瓷结合强度明显下降; 烤瓷炉中预氧化3min, 钛/瓷结合强度无明显变化. 热处理使钛表面生成一层金红石型氧化层, 钛/瓷剥脱主要发生在金红石氧化层与钛之间. 采用溶胶-凝胶法经300℃处理后在钛表面制得的SnO_x涂层, 可有效隔绝氧向Ti表面的扩散, 防止钛表面的过度氧化, 提高了钛/瓷结合强度. 经SnO_x涂层处理后, 钛/瓷剥脱主要发生在SnO_x涂层内.

2011

0.0

... 但钛合金表面硬度低、耐磨性差、抗高温氧化性能差等, 限制了其在摩擦工况下的广泛应用^[5,6] ...

2008

1.198

0.293

... 但钛合金表面硬度低、耐磨性差、抗高温氧化性能差等, 限制了其在摩擦工况下的广泛应用^[5,6] ...

2008

1.941

0.0

... 钛及钛合金的表面改性技术主要有: 激光表面处理、气相沉积、电火花沉积、脉冲激光沉积、电泳沉积、离子渗碳渗氮、微弧氧化、热喷涂、表面金属镀层(化学镀、电镀)等等^{[7,8,9,10,11]} ...

2000

1.941

0.0

2006

1.941

0.0

2006

0.531

1.106

Journal of Inorganic Materials. 2006, 21(2):488-492 DOI:10.3724/SP.J.1077.2006.00488

Effects of pulse frequencies on properties of MAO coatings on pure titanium

1. State Key Laboratory for Superhard Materials, Jilin University, Changchun 130012, China; 2. College of Science and Engineering, Yanbian University, Yanji 133002, China; 3. College of Physics, Jilin University, Changchun 130021, China

Microarc oxidation coatings were prepared on pure titanium substrates in a Na₂CO₃ and Na₂SiO₃ electrolytic solution by microarc oxidation with the pulse frequency of 500～8000Hz, the effects of pulse frequencies on growth kinetics, surface morphology and phase composition of the coatings were studied.
The result shows that the coating growth rate is dependent on the pulse
frequency. When the frequency is less than 2000Hz, with the increase of frequencies, the coating growth rate decreases sharply, while the frequency is greater than 4000Hz, it keeps almost invariable with the treating frequency increased. The coatings consist of plentiful rutile and anatase, and a small quantity of unsaturated oxideTiO_2-x, (0.022-x reduces gradually with the increase of the frequency. The coating surface is porous, with the frequency increasing, the roughness and micropore size of the coating surface decrease gradually, and the pore number increases little by little.

在Na₂CO₃-Na₂SiO₃电解液中, 利用微弧氧化技术在纯钛试样表面制备了氧化膜, 并研究了脉冲频率(500～8000Hz)对膜层生长、相组成及表面形貌的影响. 结果表明: 当脉冲频率<2000Hz时, 膜层的生长速率随频率增加迅速减小, 当>4000Hz时, 其生长速率几乎和频率无关. 微弧氧化膜主要由锐钛矿和金红石相TiO₂及少量不饱和氧化物TiO_2-x(0.022的相对含量与频率无关, 而TiO_2-x随频率的增加而逐渐减少. 氧化膜表面多孔, 随着频率的增加, 膜表面的粗糙度和微孔尺寸逐渐减小, 而微孔的密度逐渐增加.

2010

0.531

1.106

Journal of Inorganic Materials. 2010, 25(4):391-395 DOI:10.3724/SP.J.1077.2010.00391

High-speed deposition of oriented TiN_x films by laser metal-organic chemical vapor deposition

1. Engineering Research Center of Nano-geomaterials of Ministry of Education, School of Materials Science and Chemical Engineering, China University of Geosciences, Wuhan 430074, China; 2. Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan

TiN_xfilms were prepared on Al2O3 substrates by laser chemical vapor deposition (LCVD). The effects of laser power (PL), pre-heatment temperature (T_pre) and total pressure in the main chamber (P_tot) on the orientation and deposition rate (Rdep) of TiNx films were investigated. The deposited TiNx films were characterized by Xray diffraction (XRD), atomic emission spectrometry (AES) and field emission scanning electron microscope (FESEM). The results showed that the composition in TiN_x films was uniform, and the orientation was relative to the T_pre, which changed from (111) to (200) orientation with increasing T_pre. The orientation was consistent with its microstructure. The Rdep of TiNx films increased with increasing P_L, showing a maximum (90μm/h) at P_L = 100W at a deposition area of about 300mm², which was higher than that of TiN_x films prepared by other methods.

采用激光化学气相沉积（LCVD）技术在氧化铝衬底上制备了高取向的TiN_x薄膜,重点研究了激光功率（PL）、衬底预热温度（T_pre）和沉积总压力（P_tot）对薄膜取向和沉积速率的影响,采用X射线衍射（XRD）、俄歇能谱（AES）和场发射扫描电镜（FESEM）对薄膜组成和结构进行了表征.结果表明：所得到的TiN_x薄膜成分均匀,其取向与衬底预热温度有关,随着预热温度的升高,TiNx薄膜的取向由（111）变为（200）,薄膜的取向与其微观结构一致.TiN_x薄膜的沉积速率随着激光功率升高而增大,在P_L=100W时,达到最大值90μm/h（沉积面积为300mm²）,显著高于采用其它方法制备的TiN_x薄膜.

2001

0.612

0.835

Acta Metall. Sinica. 2001, 37(3):315-320

An in situ formed TiC particle reinforcement composite coating induced by laser melting on surface of alloy Ti6Al4V and its wearing performance

以Ti,Cr3C2混合粉末作为预置合金涂层,采用YAG固体激光器进行激光熔覆处理,在Ti6A14V合金表面制备出原位自生TiC颗粒增强钛基复合材料涂层.实验结果表明,采用合适的合金粉末成分和激光辐照能量密度,可以获得增强相TiC弥散分布的钛基复合材料熔覆层,熔覆层结晶致密,且与复合材料基体润湿性良好,熔覆层中复合材料的基体组织随预置合金粉末成分的改变而变化.摩擦磨损实验结果表明,原位自生TiC/Ti复合材料熔覆层可明显改善Ti6Al4V合金的表面硬度和摩擦磨损性能.

... 激光表面处理技术具有能量密度高, 加工速度快、可对零件进行选区加工、热影响区小、稀释率低、工件热变形小等优点, 主要包括激光表面合金化、激光熔覆、激光淬火(激光相变硬化、激光重熔)等^[12] ...

2011

2.112

0.0

... 国内外对钛及钛合金的激光表面改性进行了大量的研究, 主要集中于钛及钛合金的激光表面硼化、氮化、复合合金化、激光熔覆镍、钴、铁基涂层和钛铝金属间化合物涂层^[13,14,15] ...

2007

2.112

0.0

2011

1.743

0.0

Tribol. Lett.. 2011, 42(2):151-159 DOI:10.1007/s11249-011-9756-z

Improvement of the oxidation and wear resistance of pure Ti by laser-cladding Ti₃Al coating at elevated temperature

<li>1.State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, 730000, Lanzhou, China</li><li>2.Graduate University of Chinese Academy of Sciences, 100039, Beijing, China</li>

Abstract
Ti₃Al coating was in situ synthesized successfully on pure Ti substrate by laser-cladding technology using aluminum powder as the precursor. The composition and microstructure of the prepared coating were analyzed by transmission electron microscopy, scanning electron microscopy (SEM), and X-ray diffraction technique. Thermal gravimetric analysis was used to evaluate the high-temperature oxidation resistance of the Ti₃Al coating. The friction and wear behavior was tested through sliding against Si₃N₄ ball at elevated temperature of 20, 100, 300, and 500°C. The morphologies of the worn surfaces and wear debris were also analyzed by SEM and three-dimensional non-contact surface mapping. The results show that the Ti₃Al coating with high microhardness, high-temperature oxidation resistance, and high temperature wear resistance. The pure Ti substrate is dominated by severe adhesion wear, abrasive wear, fracture, and severe plastic deformation at lower temperature, and severe adhesion wear, abrasive wear, plastic deformation, oxidation, and nitriding wear at higher temperature, whereas the Ti₃Al coating experiences only moderate abrasive and adhesive wear when sliding against the Si₃N₄ ceramic ball counterpart. In addition, the wear debris of the laser-cladding Ti₃Al coating sliding and Si₃N₄ friction pairs are much smaller than that of pure Ti substrate and Si₃N₄ friction pairs at elevated temperature.

2010

0.612

0.835

Acta Metall Sinica. 2010, 46(6):761-768 DOI:10.3724/SP.J.1037.2009.00685

Microstructure of in situ TiN-Ti₅Si₃ composites prepared by selective laser melting

1. College of Materials Science and Technology; Nanjing University of Aeronautics and Astronautics; Nanjing 210016 2. Fraunhofer–Institut f¨ur Lasertechnik ILT; Aachen D–52074; Germany 3. Lehrstuhl fur Lasertechnik LLT; Rheinisch–Westfalische Technische Hochschule (RWTH) Aachen; Aachen D–52074; Germany

The selective laser melting (SLM) was used to process the high–energy ball milled Si₃N₄–Ti (mole ratio of 1∶9) nanocomposite powder in which the average grain sizes of Si₃N₄ and Ti were both less than 20 nm. The TiN reinfrced Ti₅Si₃ matrix in situ composites were prepard by means of the synthesis reaction 9Ti+Si₃N₄=4TiN+Ti₅Si₃ . s the milling time increased, thaverge particle size of te milled Si₃N₄–Ti composite powder decreased and the resultant specific surface area increased. The densification level of laser processed TiN–Ti₅Si₃ composites increased accordingly to 97.2%. The morphologies of TiN reinforcing phase in the corresponding SLM processed structures experienced a successive change from a poly–angular shape to a near–spherical shape and finally to a dendritic shape.

利用高能球磨制备了Si₃N₄-Ti(摩尔比1∶9)纳米复合粉末, Si₃N₄和Ti平均晶粒尺寸均小于20 nm, 之后进行选区激光熔化成型,通过9Ti+Si₃N₄=4TiN+Ti₅Si₃反应生成TiN增强Ti₅Si₃基原位复合材料. 延长球磨时间, Si₃N₄-Ti复合粉末颗粒细化且比表面积增加,激光成型的TiN-Ti₅Si₃复合材料致密度可增至97.2%, 成型组织中TiN增强相形貌经历多棱角状→近圆形→枝晶状的转变.

... 63 g/cm³)、高熔点(2043 K)以及良好的抗高温氧化和高温稳定性等优点, 具有高温工程应用的前景^[16,17,18] ...

1999

0.0

... 63 g/cm³)、高熔点(2043 K)以及良好的抗高温氧化和高温稳定性等优点, 具有高温工程应用的前景^[16,17,18] ...

2011

1.941

0.0

... 63 g/cm³)、高熔点(2043 K)以及良好的抗高温氧化和高温稳定性等优点, 具有高温工程应用的前景^[16,17,18] ...

2002

0.0

2006

1.941

0.0

2003

0.0

2011

1.213

0.0

J. Tribol. 2011, 133(1):1-7

Microstructure and tribological properties of ZrB₂-containing composite coating produced on pure Ti Substrate by laser surface alloying

GUO C , ZHOU J , ZHAO J

... 为了对比Ti₅Si₃涂层的耐磨性能, 文中引用了钛在相同测试条件下的磨损体积^[22] ...

1999

0.0

... 根据文献报道, 激光表面处理过程中, 材料表面激光束照射处的温度可以用公式(1)进行估算^[23,24]: ...

... K)^{[23, 25]} ...

1995

0.469

0.0

... 根据文献报道, 激光表面处理过程中, 材料表面激光束照射处的温度可以用公式(1)进行估算^[23,24]: ...

2001

0.0

... K)^{[23, 25]} ...

1994

0.0

0.1571

... 另外,纳米级晶粒的形成可归因于激光熔覆是一个快速加热、快速冷却的过程, 冷却速度可达到10⁶℃/s^[26], 在如此高的冷却速度下, 使凝固组织细化 ...

1990

0.0

... 从图6可以看到Ti₅Si₃涂层的摩擦因数受载荷的影响显著, 即摩擦因数都随载荷的增加先增大后减小, 根据摩擦学原理, 这一现象可以用公式(2)进行解释^[27,28]: ...

2001

1.262

0.0

1953

0.71

0.0

... 从磨损的体积损失随载荷变化的曲线(图 7)可以看出, Ti₅Si₃涂层和钛的磨损体积均随载荷的增加而增加, 这与阿查德磨损定理相一致^[29] ...

... 从图7 还可看出Ti₅Si₃涂层与钛基材相比, 磨损体积较小(钛基材的磨损体积约是Ti₅Si₃涂层的2倍), 说明Ti₅Si₃涂层相对于钛基材具有较好的耐磨性能, 可见激光熔覆Ti₅Si₃涂层可以提高钛的耐磨性能, 这可归因于激光Ti₅Si₃涂层相对于钛基材有较高的表面硬度, 根据阿查德磨损定理^[29]可知, 提高硬度有利于提高材料的耐磨性能 ...

1999

0.0

... 此外, 摩擦表面可能生成氧化物或转移膜, 导致摩擦对偶之间的作用力减弱, 最终导致摩擦系数的减小^[30] ...

2002

0.0

... 另外, 产生球状的磨屑是由块状的磨屑在摩擦过程中来不及逸出磨痕经过研磨的结果^[31] ...