Nanomechanics of single crystalline tungsten nanowires
Nanomechanics of single crystalline tungsten nanowires
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DOI：
10.1155/2008/638947
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发表时间：
2008-01-01
影响因子：
--
通讯作者：
Hassel, Achim Walter
中科院分区：
文献类型：
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作者：
Cimalla, Volker;Roehlig, Claus-Christian;Hassel, Achim Walter
以定向凝固NiAl-W合金为原料，采用化学释放法制备了单晶钨纳米线。电子背散射衍射（EBSD）证明它们是具有相同晶体取向的单晶。对直径为100-300 nm的金属丝进行了机械研究，如弯曲试验、侧向力测量和机械共振测量。该线可以直接使用微镊子，作为单夹纳米线或双夹纳米桥。机械测试显示出由于小尺寸而导致的这种脆性材料的令人惊讶的高柔性。力位移测量单夹紧W纳米线的AFM测量允许测定的杨氏模量为332 GPa非常接近的体积值为355 GPa。采用双钳位W纳米线作为在117 kHz下运行的磁动驱动谐振器中的谐振振荡纳米线。发现从该设置确定的杨氏模量高于450 GPa，这很可能是由附加质量负载引起的共振频率的偏移引起的伪影。版权所有（C）2008 Volker Cimalla et al.
Single crystalline tungsten nanowires were prepared from directionally solidified NiAl-W alloys by a chemical release from the resulting binary phase material. Electron back scatter diffraction (EBSD) proves that they are single crystals having identical crystallographic orientation. Mechanical investigations such as bending tests, lateral force measurements, and mechanical resonance measurements were performed on 100-300 nm diameter wires. The wires could be either directly employed using micro tweezers, as a singly clamped nanowire or in a doubly clamped nanobridge. The mechanical tests exhibit a surprisingly high flexibility for such a brittle material resulting from the small dimensions. Force displacement measurements on singly clamped W nanowires by an AFM measurement allowed the determination of a Young's modulus of 332 GPa very close to the bulk value of 355 GPa. Doubly clamped W nanowires were employed as resonant oscillating nanowires in a magnetomotively driven resonator running at 117 kHz. The Young's modulus determined from this setup was found to be higher 450 GPa which is likely to be an artefact resulting from the shift of the resonance frequency by an additional mass loading. Copyright (C) 2008 Volker Cimalla et al.