scholarly journals Evaluation of elastoplastic properties of brittle sandstone at microscale using micro‐indentation test and simulation

2020 ◽  
Vol 8 (10) ◽  
pp. 3490-3501
Author(s):  
Rui Song ◽  
Yao Wang ◽  
Shuyu Sun ◽  
Mengmeng Cui ◽  
Jianjun Liu
Keyword(s):  
Indentation Test ◽  
Elastoplastic Properties ◽  
Brittle Sandstone ◽  
Micro Indentation

Can indentation technique measure unique elastoplastic properties?

2009 ◽  
Vol 24 (3) ◽  
pp. 784-800 ◽  
Author(s):  
Ling Liu ◽  
Nagahisa Ogasawara ◽  
Norimasa Chiba ◽  
Xi Chen
Keyword(s):  
Critical Strain ◽  
Indentation Test ◽  
Strain Curve ◽  
Spherical Indentation ◽  
Plastic Behavior ◽  
Displacement Curve ◽  
Application Range ◽  
Indentation Technique ◽  
Elastoplastic Properties ◽  
Force Displacement

Indentation is widely used to extract material elastoplastic properties from measured force-displacement curves. Many previous studies argued or implied that such a measurement is unique and the whole material stress-strain curve can be measured. Here we show that first, for a given indenter geometry, the indentation test cannot effectively probe material plastic behavior beyond a critical strain, and thus the solution of the reverse analysis of the indentation force-displacement curve is nonunique beyond such a critical strain. Secondly, even within the critical strain, pairs of mystical materials can exist that have essentially identical indentation responses (with differences below the resolution of published indentation techniques) even when the indenter angle is varied over a large range. Thus, fundamental elastoplastic behaviors, such as the yield stress and work hardening properties (functions), cannot be uniquely determined from the force-displacement curves of indentation analyses (including both plural sharp indentation and deep spherical indentation). Explicit algorithms of deriving the mystical materials are established, and we qualitatively correlate the sharp and spherical indentation analyses through the use of critical strain. The theoretical study in this paper addresses important questions of the application range, limitations, and uniqueness of the indentation test, as well as providing useful guidelines to properly use the indentation technique to measure material constitutive properties.

Current transients during repeated micro-indentation test of passive iron surface in pH 8.4 borate buffer solution

2007 ◽  
Vol 9 (7) ◽  
pp. 1672-1676 ◽  
Author(s):  
Takatoshi Yamamoto ◽  
Koji Fushimi ◽  
Masahiro Seo ◽  
Shiro Tsuri ◽  
Tetsuo Adachi ◽  
...  
Keyword(s):  
Indentation Test ◽  
Borate Buffer ◽  
Iron Surface ◽  
Borate Buffer Solution ◽  
Buffer Solution ◽  
Micro Indentation ◽  
Current Transients

ELASTO-PLASTIC PROPERTIES OF Mo-MODIFIED Ti DEDUCED FROM INDENTATION TESTS AND FINITE ELEMENT ANALYSIS

2019 ◽  
Vol 26 (07) ◽  
pp. 1850225
Author(s):  
YONG MA ◽  
ZHAO YANG ◽  
SHENGWANG YU ◽  
BING ZHOU ◽  
HONGJUN HEI ◽  
...  
Keyword(s):  
Finite Element ◽  
Surface Treatment ◽  
Load Capacity ◽  
Indentation Test ◽  
Element Analysis ◽  
Plastic Properties ◽  
Polynomial Expression ◽  
Indentation Tests ◽  
Graded Material ◽  
Micro Indentation

The aim of this paper is to establish an approach to quantitatively determine the elasto-plastic parameters of the Mo-modified Ti obtained by the plasma surface alloying technique. A micro-indentation test is conducted on the surface under 10[Formula: see text]N. Considering size effects, nanoindentation tests are conducted on the cross-section with two loads of 6 and 8[Formula: see text]mN. Assuming nanoindentation testing sublayers are homogeneous, finite element reverse analysis is adopted to determine their plastic parameters. According to the gradient distributions of the elasto-plastic parameters with depth in the Mo-modified Ti, two types of mathematical expressions are proposed. Compared with the polynomial expression, the linear simplified expression does not need the graded material to be sectioned and has practical utility in the surface treatment industry. The validation of the linear simplified expression is verified by the micro-indentation test and corresponding finite element forward analysis. This approach can assist in improving the surface treatment process of the Mo-modified Ti and further enhancing its load capacity and wear resistance.

S0304-1-3 Evaluation of Crystal Orientation of Ti-Mo Alloys Using Micro Indentation Test

2010 ◽  
Vol 2010.1 (0) ◽  
pp. 265-266
Author(s):  
Noriaki KIMURA ◽  
Ichiro SHIMIZU ◽  
Naoya TADA ◽  
Yoshito TAKEMOTO
Keyword(s):  
Crystal Orientation ◽  
Indentation Test ◽  
Micro Indentation

203 Evaluation of Mechanical Properties of Biomineral by Means of Micro-Indentation Test

2015 ◽  
Vol 2015.51 (0) ◽  
pp. _203-1_-_203-2_
Author(s):  
Junki HOSHINO ◽  
Kyuhei MATSUDA ◽  
Osamu TAKAKUWA ◽  
Hitoshi SOYAMA
Keyword(s):  
Mechanical Properties ◽  
Indentation Test ◽  
Micro Indentation

scholarly journals Size Effect and Geometrical Effect of Polycrystals and Thin Film/Substrate System in Micro-indentation Test

2002 ◽  
Vol 731 ◽  
Author(s):  
Y. Wei ◽  
M. Zhao ◽  
X. Wang ◽  
S. Tang
Keyword(s):  
Thin Film ◽  
Size Effect ◽  
Strain Gradient ◽  
Indentation Test ◽  
Strain Gradient Theory ◽  
Thickness Effect ◽  
Geometrical Effect ◽  
Film Substrate ◽  
Micro Indentation ◽  
Measured Hardness

AbstractMicro-indentation test at scales on the order of sub-micron has shown that the measured hardness increases strongly with decreasing indent depth or indent size, which is frequently referred to as the size effect. Simultaneously, at micron or sub-micron scale, the material microstructure size also has an important influence on the measured hardness. This kind of effect, such as the crystal grain size effect, thin film thickness effect, etc., is called the geometrical effect. In the present research, in order to investigate the size effect and the geometrical effect, the micro-indentation experiments are carried out respectively for single crystal copper and aluminum, for polycrystal aluminum, as well as for a thin film/substrate system, Ti/Si3N4. The size effect and geometrical effect are displayed experimentally. Moreover, using strain gradient plasticity theory, the size effect and the geometrical effect are simulated. Through comparing experimental results with simulation results, the length-scale parameter appearing in the strain gradient theory for different cases is predicted. Furthermore, the size effect and the geometrical effect are interpreted using the geometrically necessary dislocation concept and the discrete dislocation theory.

Surface and Bulk Stiffness of the Mature Porcine Cartilage-Like Tissue Repaired With a Scaffold-Free, Stem Cell-Based Tissue Engineered Construct (TEC)

2009 ◽  
Author(s):  
Ryosuke Nansai ◽  
Mamoru Ogata ◽  
Junichi Takeda ◽  
Wataru Ando ◽  
Norimasa Nakamura ◽  
...  
Keyword(s):  
Indentation Test ◽  
Compressive Properties ◽  
Normal Cartilage ◽  
Atomic Force ◽  
Engineering Technique ◽  
Macro Scale ◽  
Immunological Effects ◽  
Tissue Engineering Technique ◽  
Micro Indentation

Since the healing capacity of articular cartilage is limited, it is important to develop cell-based therapies for the repair of cartilage. Although synthetic or animal-derived scaffolds are frequently used for effective cell delivery long-term safety and efficiency of such scaffolds still remain unclear. We have been developing a new tissue engineering technique for cartilage repair using a scaffold-free tissue engineered construct (TEC) bio-synthesized from synovium-derived mesenchymal stem cells (MSCs) [1]. As the TEC specimen is composed of cells with their native extracellular matrix, we believe that it is free from concern regarding long term immunological effects. Fujie et al. found in a micro indentation test using an atomic force microscope (AFM) that the immature porcine cartilage-like tissue repaired with TEC exhibited lower stiffness as compared with normal cartilage in immature porcine femur [2], although the macro-scale stiffness of the repaired tissue was almost same as that of the normal cartilage [3]. In the present study, we investigated the macro and micro-compressive properties of mature porcine cartilage-like tissue repaired with TEC.

Sign in / Sign up

Export Citation Format

Share Document