Notch insensitive fracture in nanoscale thin films

被引：55

作者：

Kumar, S. ^{[1
]}

Haque, M. A. ^{[1
]}

Gao, H. ^{[2
]}

机构：

[1] Penn State Univ, Dept Mech & Nucl Engn, University Pk, PA 16802 USA

[2] Brown Univ, Div Engn, Providence, RI 02912 USA

来源：

APPLIED PHYSICS LETTERS | 2009年 / 94卷 / 25期

基金：

美国国家科学基金会;

关键词：

fracture mechanics; metallic thin films; nanostructured materials; stress effects; transmission electron microscopy; NANOCRYSTALLINE MATERIALS; MECHANICAL-PROPERTIES; DEFORMATION;

D O I：

10.1063/1.3157276

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

To study the effect of stress concentration at the nanoscale, we performed fracture experiments on single edge notched thin film specimens inside the transmission electron microscope. Even at about 4 GPa stress at the notch tip, the specimens failed far away from the notch at places with no apparent stress concentration. The in situ electron microscopy showed evidence of little or no plastic deformation at the notch tip. We propose that the apparent notch insensitivity arises from the breakdown of the classical fracture mechanics at the nanoscale, where materials fail by reaching a uniform rupture stress and not due to stress concentration.

引用

页数：3

共 15 条

[1]

Baretzky B, 2005, REV ADV MATER SCI, V9, P45

[2] Cracking and adhesion at small scales: atomistic and continuum studies of flaw tolerant nanostructures [J].

Buehler, Markus J. ;

Yao, Haimin ;

Gao, Huajian ;

Ji, Baohua .

MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING, 2006, 14 (05) :799-816

[3] Self-consistent modelling of the plastic deformation of FCC polycrystals and its implications for diffraction measurements of internal stresses [J].

Clausen, B ;

Lorentzen, T ;

Leffers, T .

ACTA MATERIALIA, 1998, 46 (09) :3087-3098

[4] Intergranular and interphase microstresses [J].

Dye, D ;

Stone, HJ ;

Reed, RC .

CURRENT OPINION IN SOLID STATE & MATERIALS SCIENCE, 2001, 5 (01) :31-37

[5] Materials become insensitive to flaws at nanoscale:: Lessons from nature [J].

Gao, HJ ;

Ji, BH ;

Jäger, IL ;

Arzt, E ;

Fratzl, P .

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2003, 100 (10) :5597-5600

[6] Flaw tolerance in a thin strip under tension [J].

Gao, HJ ;

Chen, SH .

JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME, 2005, 72 (05) :732-737

[7] Deformation mechanisms in free-standing nanoscale thin films:: A quantitative in situ transmission electron microscope study [J].

Haque, MA ;

Saif, MTA .

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2004, 101 (17) :6335-6340

[8]

HASSANPOUR PA, 2006, P SPIE INT SOC UNPUB

[9] Plane stress fracture toughness of freestanding nanoscale thin films [J].

Hosokawa, H. ;

Desai, A. V. ;

Haque, M. A. .

THIN SOLID FILMS, 2008, 516 (18) :6444-6447

[10] Mechanical properties of nanocrystalline materials [J].

Meyers, MA ;

Mishra, A ;

Benson, DJ .

PROGRESS IN MATERIALS SCIENCE, 2006, 51 (04) :427-556

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