Mechanical Characteristics Of Individual TiO₂ Nanowire And TiO₂ Nanowires Bundle On Micro-manipulator Nanoprobe System

One-dimensional nanostructures such as nanowires, nanobelts and nanorods have attracted tremendous attention in recent years due to their exceptional properties and novel potential applications. These structures exhibit outstanding mechanical, electrical, thermal and optical properties. Especially, mechanical characterization of nanowires is necessary to establish the feasibility of replacing current electrical and optical devices with NWs integrated devices based on reliability requirements.In this paper, a new working platform was put forward, it combined the MM3 A micro-manipulation system with a scanning electron microscope(SEM). Mechanical properties of titanium dioxide nanowires(Ti O2 NWs), either an individual or a bundle, could be measured simultaneously by bending test method. The individual Ti O2 NW was tested as a micro-cantilever model and the Ti O2 NWs bundle was studied with a nanoscale three-point bending test. The main contents and the innovations were summarized as follows:1. A new method based on micro-cantilever beam model to measure the mechanical property of an individual Ti O2 nanowire in nanoscale was put forward. Now takes an individual Ti O2 NW as example, whose diameter is 320 nm and length is5.6 μm, described the test process in detail. The lateral forces vs deformation(F-d) curve was measured by bending the free end using the MM3 A micro-manipulator probe; the F-d curve was K=0.975N/m by linear fitting; the Young’s modulus was 110.77 GPa. Moreover, analyzed the testing datum of 17 individual NWs,their diameters range from 270 to 920 nm, the mean value of Young’s modulus was 120.39 GPa,and standard deviation was 37.96 GPa. These analyzed results of the relationship of the parameters proved that there was no obvious size effect of individual Ti O2 NW while its diameter ranging from 100 to 1000 nm.2. Another new method based on double-clamped beam model to measure the mechanical property of a Ti O2 NWs bundle in microscale was designed. Taken the Ti O2 NWs bundle as example, whose diameter is 25.6μm and length is 1.38 mm. With the same test environment and operation, the F-d curve was measured, the slope of F-d curve was analyzed as K=149.8 N/m,and the Young’s modulus was calculated as 101 GPa based on the theory formula of double-clamped beam model at last. Moreover, the testing datum of 10 NWs bundles were analyzed, their diameters were range from 25 to 72μm, the mean value of Young’s modulus ofTi O2 NWs bundle was 92.01 GPa, and standard deviation was 27.24 GPa. There was no obvious size effect as its diameter ranging from 10 to 100μm.In conclusion, the mechanical properties of an individual Ti O2 NW and a Ti O2 NWs bundle were measured quickly and accurately, based on the mew test platform and bending test method.Firstly, the material in different forms or under different size remains the same young’s modulus,which is its properties. Moreover, this new work platform and new testing method could be widely applied to the mechanical measurement of one-dimensional micro/nano materials, and the results were accurately.