Microscale deformation behavior of amorphous/nanocrystalline multilayered pillars
Microscale deformation behavior of amorphous/nanocrystalline multilayered pillars
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DOI：
10.1016/j.tsf.2010.04.096
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发表时间：
2010-10-01
期刊：
影响因子：
2.1
通讯作者：
Huang, J. C.
中科院分区：
文献类型：
--
作者：
Liu, M. C.;Lee, C. J.;Huang, J. C.
近年来，金属玻璃在微电子机械系统(MEMS)中得到了广泛的研究和应用。然而，块体和薄膜形式的金属玻璃的脆性不可避免地施加了限制。本研究应用了在脆性二元金属玻璃(TFMG)层下面增加一层纳米金属薄膜的新思想。这种金属薄膜需要在模数和强度上足够强，并且需要以适当的薄膜取向沉积。面心立方的Cu{111}薄膜表现出太软，体心立方的Mo{110}薄膜表现为太脆，而六方紧密堆积的Zr{0001}薄膜符合上述要求。纳米晶Zr{0001}层可以通过纳米孪生机制吸收和调节在ZrCu薄膜金属玻璃层中形成的剪切带。原始脆性的ZrCuTFMG具有很高的延性，其半均匀塑性变形量为55%，比大多数纯金属更具延展性。非晶-晶界面经明显的塑性变形后表现出良好的应变相容性。这一发现将对用于MEMS设计的TFMG/金属多层结构产生重大影响。(C)2010爱思唯尔B.V.保留所有权利。
Metallic glasses have recently been extended their research and application in micro-electro-mechanical systems (MEMS). However, the brittle nature of metallic glasses in the bulk and thin film forms inevitably imposes limitation. The current study applies the new idea to adopt a thin layer of nanocrystalline metal film beneath the brittle binary ZrCu thin film metallic glass (TFMG) layer. This metal film needs to be sufficiently strong in modulus and strength and needs to be deposited with the appropriate film orientation. The face-centered cubic Cu {111} film appears to be too soft, the body-centered cubic Mo {110} film behaves to be too brittle, but the hexagonal close-packed Zr {0001} film matches all above requirements. The shear bands initiated in the ZrCu thin film metallic glass layer can be absorbed and accommodated by the nanocrystalline Zr {0001} layer via the nano-twinning mechanism. The original brittle ZrCu TFMG, with the inclusion of a Zr layer beneath, can behave highly ductile with semi-uniform plastic deformation of 55%, even more ductile than most pure metals. The amorphous-crystalline interface exhibits good strain compatibility after appreciable plastic deformation. This finding can impose great impact on the TFMG/metal multilayer structures useful for MEMS design. (C) 2010 Elsevier B.V. All rights reserved.