scholarly journals Measuring fracture toughness of coatings using focused-ion-beam-machined microbeams – ERRATUM

2017 ◽  
Vol 32 (6) ◽  
pp. 1211-1211 ◽  
Author(s):  
D. Di Maio ◽  
S.G. Roberts
Keyword(s):  
Fracture Toughness ◽  
Focused Ion Beam ◽  
Ion Beam

The evaluation of the composition dependence of fracture toughness of Al3Nb alloys by using micro-size fracture testing

MRS Advances ◽  
2017 ◽  
Vol 2 (26) ◽  
pp. 1405-1410
Author(s):  
Nobuhiro Matsuzaki ◽  
Ken-ichi Ikeda ◽  
Seiji Miura ◽  
Nobuaki Sekido ◽  
Takahito Ohmura
Keyword(s):  
Fracture Toughness ◽  
Single Crystal ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Two Phase ◽  
Fracture Testing ◽  
Average Value ◽  
Chevron Notch ◽  
Polycrystalline Alloys ◽  
Oxidation Resistant

ABSTRACTAl3Nb is known as a high oxidation resistant material, while it is quite brittle. As the fracture toughness of Al3Nb single crystal and its dependence on the composition are not obtained, the micro-sized fracture testing proposed by Suzuki et al. was performed. Al3Nb single crystal micron-order size cantilevers with a chevron-notch were fabricated in a grain of two-phase polycrystalline alloys by using FIB (Focused Ion Beam). From the load-displacement curves during the bending by a nanoindenter, the average value of fracture toughness of Nb-rich Al3Nb is evaluated to be 2.90 MPam1/2, while the fracture toughness of Al-rich Al3Nb is also evaluated to be 2.82 MPam1/2. From this result, the fracture toughness of Al3Nb is less dependent on its Al/Nb ratio. Furthermore the fracture toughness of Al3 (Nb, V) was evaluated to be 2.82 MPam1/2.The fracture toughness of Al3Nb is seemingly insensitive to V addition.

Fracture Toughness of Titanium - Titanium Nitride Multi-Layer Thin Film

2008 ◽  
Author(s):  
Mohan Prasad Manoharan ◽  
Amit Desai ◽  
Amanul Haque
Keyword(s):  
Thin Film ◽  
Fracture Toughness ◽  
Titanium Nitride ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
New Class ◽  
Tin Coatings ◽  
Film Specimen ◽  
Cantilever Bending ◽  
Layer Thin Film

Thin film specimens of titanium - titanium nitride multilayer erosion resistant coating were prepared using liftout technique in Focused Ion Beam - Scanning Electron Microscope (SEM). The fracture toughness of the thin film specimen was measured in situ using a cantilever bending experiment in SEM to be 11.33 MPa/m0.5, twice as much as conventional TiN coatings. Ti–TiN multi-layer coatings are part of a new class of advanced erosion resistant coatings and this paper discusses an experimental technique to measure the fracture toughness of these coatings.

A Membrane Deflection Fracture Experiment to Investigate Fracture Toughness of Freestanding MEMS Materials

2003 ◽  
Vol 795 ◽  
Author(s):  
H. D. Espinosa ◽  
B. Peng
Keyword(s):  
Thin Film ◽  
Fracture Toughness ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
National Laboratory ◽  
Argonne National Laboratory ◽  
Mean Value ◽  
Advanced Materials ◽  
Ultrananocrystalline Diamond ◽  
Membrane Deflection

ABSTRACTThis paper presents a novel Membrane Deflection Fracture Experiment (MDFE) to investigate the fracture toughness of MEMS and other advanced materials in thin film form. It involves the stretching of freestanding thin-film membranes, in a fixed-fixed configuration, containing pre-existing cracks. The fracture behavior of ultrananocrystalline diamond (UNCD), a material developed at Argonne National Laboratory, is investigated to illustrate the methodology. When the fracture initiates from sharp cracks, produced by indentation, the fracture toughness was found to be 4.7 MPa m1/2. When the fracture initiates from blunt notches with radii about 100 nm, machined by focused ion beam (FIB), the mean value of the apparent fracture toughness was found to be 7.2 MPa m1/2. Comparison of these two values, using the model proposed by Drory et al. [9], provides a correction factor of 2/3, which corresponds to a mean value of ρ/2x=1/2.

Micro Fracture Toughness Testing of TiAl Based Alloys with a Fully Lamellar Structure

2004 ◽  
Vol 842 ◽  
Author(s):  
K. Takashima ◽  
T. P. Halford ◽  
D. Rudinal ◽  
Y. Higo ◽  
M. Takeyama
Keyword(s):  
Fracture Toughness ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Testing Machine ◽  
High Fracture Toughness ◽  
Fracture Mechanisms ◽  
High Fracture ◽  
Fundamental Information ◽  
Micrometer Scale ◽  
Fully Lamellar

ABSTRACTA micro-sized testing technique has been applied to investigate the fracture properties of lamellar colonies in a fully lamellar Ti-46Al-5Nb-1W alloy. Micro-sized cantilever specimens with a size ≈ 10 × 10 × 50 μm3 were prepared by focused ion beam machining. Notches with a width of 0.5 μm and a depth of 5 μm were also introduced into the micro-sized specimens by focused ion beam machining. Fracture tests were successfully completed using a mechanical testing machine for micro-sized specimens at room temperature. The fracture toughness (KQ) values obtained were in the range 1.4–7 MPam1/2. Fracture surface observations indicate that these variations are attributable to differences in local lamellar orientations ahead of the notch. These fracture toughness values are also lower than those having been previously reported in conventional samples. This may be due the absence of significant extrinsic toughening mechanisms in these micro-sized specimens. Fracture mechanisms of these alloys are also considered on the micrometer scale. The results obtained in this investigation give important and fundamental information on the development of TiAl based alloys with high fracture toughness.

Experiment Research for Fracture Toughness of PAN-Based Carbon Fibers

2011 ◽  
Vol 462-463 ◽  
pp. 1361-1366 ◽  
Author(s):  
Bo Ming Zhang ◽  
Yu Fen Wu
Keyword(s):  
Fracture Toughness ◽  
Tensile Strength ◽  
Carbon Fibers ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Testing Machine ◽  
High Strength ◽  
Carbon Filaments ◽  
Fracture Theory ◽  
In Virtue Of

For the sake of the carbon filaments’ fracture toughness, using the focused ion beam (FIB) to etch the carbon fibers and got different tensile strength, and all specimens were stretched on an Instron-type filaments testing machine and got the samples’ tensile strength, The crack-to-mirror size ratio was assumed as a constant, In virtue of Griffith fracture theory, Fracture toughness (KΙC) of representative high-strength type PAN (polyacrylonitrile)-based carbon fibers, Torayca T300 and T800, were estimated to be 1MPam1/2 from the tensile strength vs. fracture mirror size relation.

Microscale Fracture Toughness Testing of TiAl PST Crystals

2008 ◽  
Vol 1128 ◽  
Author(s):  
Daisuke Miyaguchi ◽  
Masaaki Otsu ◽  
Kazuki Takashima ◽  
Masao Takeyama
Keyword(s):  
Fracture Toughness ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Testing Machine ◽  
Type Specimens ◽  
Toughening Mechanisms ◽  
Two Phase ◽  
Fracture Toughness Testing ◽  
Crack Wake ◽  
Toughness Testing

AbstractA microscale fracture testing technique has been applied to examine the fracture properties of lamellar in TiAl PST crystals. Micro-sized cantilever specimens with a size ˜ 10×20×50 μm3 were prepared from Ti-48Al two-phase single crystals (PST) lamellar by focused ion beam (FIB) machining. Notches with a width of 0.5 μm and a depth of 5 μm were also introduced into the specimens by FIB. Two types of notch directions (interlamellar and translamellar) were selected when introducing the notches. Fracture tests were successfully completed using a mechanical testing machine for micro-sized specimens at room temperature. The fracture toughness (KQ) values of the interlamellar type specimens were obtained in the range 1.5–3.6 MPam1/2, while those of the translamellar specimens were 5.0–8.1 MPam1/2. These fracture toughness values are lower than those having been previously reported in conventional TiAl PST samples. For macro-sized specimens, extrinsic toughening mechanisms, including shear ligament bridging, act in the crack wake, and the crack growth resistance increases rapidly with increasing length of crack wake for lamellar structured TiAl alloys. In contrast, the crack length in microsized specimens is only 2–3 μm. This indicates that extrinsic toughening mechanisms are not activated in micro-sized specimens. This also indicates that intrinsic fracture toughness can be evaluated using microscale fracture toughness testing.

Fracture Toughness Evaluation of a Cracked Au Thin Film by Applying a Finite Element Analysis and Bulge Test

2019 ◽  
Vol 827 ◽  
pp. 196-202
Author(s):  
Hector A. Tinoco ◽  
Pavel Hutař ◽  
Benoit Merle ◽  
Mathias Göken ◽  
Tomáš Kruml
Keyword(s):  
Thin Film ◽  
Fracture Toughness ◽  
Finite Element Analysis ◽  
Finite Element ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Experimental Tests ◽  
Bulge Test ◽  
Element Analysis ◽  
Plastic Properties

This paper presents a finite element analysis of a pre-cracked freestanding gold thin film subjected to bulge test. These tests were conducted in order to determine the elasto-plastic properties and fracture toughness of the gold films. For the experimental tests, a pre-crack was introduced in the center of the film by focused ion beam (FIB) milling with a length of 10 and a width of 100nm. For the numerical fracture analysis, the problem was divided into two stages; the first stage was the development of the numerical model on the whole film without pre-crack (elasto-plastic analysis) and the second one was performed on a film portion that included the pre-crack (sub-modeling stage). Three different notches (rounded, sharp and V-sharp) were applied to calculate the stress intensity factor around the crack tip using path independent J-integral. The obtained results show that the load-deflection curves for non-cracked and pre-cracked film reproduced the experiments using the calculated elasto-plastic properties. This indicates that the proposed models presented a good correlation and robustness. Additionally, fracture toughness values were calculated between 0.288 and 0.303with J-integral values 1.037 J/m2 (elastic) and 1.136 J/m2 (elasto-plastic) which correspond with other calculations available in the literature.

Fracture toughness of Al2O3 fibers with an artificial notch introduced by a focused-ion-beam

2010 ◽  
Vol 30 (7) ◽  
pp. 1659-1667 ◽  
Author(s):  
S. Ochiai ◽  
S. Kuboshima ◽  
K. Morishita ◽  
H. Okuda ◽  
T. Inoue
Keyword(s):  
Fracture Toughness ◽  
Focused Ion Beam ◽  
Ion Beam

scholarly journals Applicability of focused Ion beam (FIB) milling with gallium, neon, and xenon to the fracture toughness characterization of gold thin films

2021 ◽  
Author(s):  
Eva I. Preiß ◽  
Benoit Merle ◽  
Yuan Xiao ◽  
Florentina Gannott ◽  
Jan P. Liebig ◽  
...  
Keyword(s):  
Thin Films ◽  
Fracture Toughness ◽  
Crack Initiation ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Experimental Designs ◽  
Milling Parameters ◽  
Gold Thin Films ◽  
Ion Species

Abstract Focused ion beam (FIB) milling is an increasingly popular technique for fabricating micro-sized samples for nanomechanical characterization. Previous investigations have cautioned that exposure to a gallium ion beam can significantly alter the mechanical behavior of materials. In the present study, the effects of gallium, neon, and xenon ions are scrutinized. We demonstrate that fracture toughness measurements on freestanding gold thin films are unaffected by the choice of the ion species and milling parameters. This is likely because the crack initiation is controlled by the local microstructure and grain boundaries at the notch, rather than by the damaged area introduced by FIB milling. Additionally, gold is not susceptible to chemical embrittlement by common FIB ion species. This confirms the validity of microscale fracture measurements based on similar experimental designs. Graphical abstract

Toughening of Brittle Materials by Dislocation Cells

2001 ◽  
Vol 7 (S2) ◽  
pp. 420-421
Author(s):  
H. Saka ◽  
W.-J. Moon ◽  
S. Horiuchi ◽  
S. Uchimura
Keyword(s):  
Fracture Toughness ◽  
Room Temperature ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Brittle Materials ◽  
Thin Foil ◽  
Vickers Indentation ◽  
Transmission Electron ◽  
Dislocation Cells ◽  
Metallurgical Processes

Many attempts have been made to improve the fracture toughness of brittle materials such as ceramics. Most of the methods developed so far make use of metallurgical processes, for example, phase transformation, refining of grains, formation of composite materials. However, these methods can not be applied universally to brittle materials which do not have such a useful metallurgical processes.Moon and Saka (1) recently showed that the fracture toughness Klc of a YAG single crystal the sub-surface of which is damaged by micro-Vickers indentation at room temperature, followed by annealing at high temperatures is improved by a factor 2 from 1.13 to 2.26MPam1/2. The fracture toughness Klc was evaluated by measuring the length of cracks which initiate at the corner of Vickers indentation(2). Transmission electron microscopy of the subsurface reveals the healing of cracks introduced by room-temperature indentation and formation of dislocation cells. The thin foil specimens were prepared using a focused ion beam (FIB) technique(3).

Sign in / Sign up

Export Citation Format

Share Document