调制周期对Ti/TiB_2多层膜的结构和力学性能的影响  

Influence of Modulation Periods on Microstructure and Mechanical Properties of Ti/TiB_2 Multilayers

作　　者：周广宏[1] 王湘鸣 印凤 庄国志[1] 夏木建[1] 丁红燕[1] 

机构地区：[1]淮阴工学院江苏省介入医疗器械研究重点实验室,江苏淮安223003

出　　处：《稀有金属材料与工程》2016年第2期498-502,共5页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51175212);江苏省介入医疗器械研究重点实验室开放基金(JR1206)

摘　　要：采用磁控溅射法制备了Ti/TiB_2周期性(T=2,3,4,6,12)多层膜,利用X射线衍射仪、场发射扫描电子显微镜分析了薄膜的相结构和表面(断面)形貌,采用纳米压痕仪、多功能摩擦摩损试验机和显微硬度计研究了多层膜的纳米硬度、弹性模量、膜基结合力以及断裂韧性。结果表明:Ti/TiB_2多层膜具有清晰的纳米层状结构,薄膜表面致密平整,与基体保持着良好的物理结合。多层膜的硬度和弹性模量随着调制周期的增加而增大,在周期T=12时,多层膜的硬度和弹性模量达到最大值,分别为35.8和349 GPa;多层膜的断裂韧性随着周期的增加呈现出先增大而后减小的趋势,当周期T=6时多层膜的断裂韧性最好,其断裂韧度为2.17 MPa·m^(1/2)。分析认为多层膜中的Ti子层可使裂纹尖端产生钝化作用,从而引起裂纹扩展路径发生偏转,提高了多层膜的断裂韧性。Ti/TiB2 multilayers with various modulation periods were prepared by a magnetron sputtering system.An X-ray diffraction was used to characterize the phase and a scanning electron microscope was applied to observe the surface and fracture cross-sectional morphologies of multilayers.The mechanical properties of the multilayers including nano-hardness,elastic modulus,adhesion and fracture toughness were evaluated with nanoindentation,universal micro materials tester and microhardness meter,respectively.The results show that the surface of multilayers is even,compact and smooth with clear nano-modulated structure and presents a good physical bonding between the coating and substrate.With the increase of the modulation periods of multilayers,the hardness and elastic modulus increase and attain the maximum values of 35.8 GPa and 349 GPa,respectively at the modulation period T=12.However,the fracture toughness of multilayers increases firstly and reaches maximum value（2.17 MPa·m^（1/2）） at the modulation period T=6 and decreases subsequently.Passivation effect occurs at the crack tip due to the insertion of Ti sub-layer in the multilayers,which leads to a path deflection of the crack propagation;as a result,the fracture toughness of the multilayers is improved.

关 键 词：Ti/TiB2多层膜 调制周期 力学性能 

分 类 号：TB383.2[一般工业技术—材料科学与工程]