scholarly journals Claw Characteristics of Culled Sows from Three Farrow-to-Finish Greek Farms. Part 2: Mechanical Indices of Hoof Horn and Their Associations with Length Measurements and Lesion Scores

2021 ◽  
Vol 8 (9) ◽  
pp. 175
Author(s):  
Sofia Chalvatzi ◽  
Georgios A. Papadopoulos ◽  
Fotios Kroustallas ◽  
Mihaela Cernat ◽  
Vassilis Skampardonis ◽  
...  
Keyword(s):  
Yield Stress ◽  
Young’S Modulus ◽  
Maximum Stress ◽  
Young's Modulus ◽  
Mechanical Efficiency ◽  
Bending Test ◽  
Lesion Score ◽  
Three Point Bending ◽  
Length Measurements ◽  
Lesion Severity

The objective of the present study was to investigate the mechanical indices of hoof horn and their association with length measurements and lesion score. The feet of 185 culled sows from three Greek farms (A: 57 sows; B: 64 sows; C: 64 sows) were used. A slice from the dorsal wall of each claw was used to assess by a three-point bending test the Young’s modulus, yield stress and aximum stress values. The available data from a companion study (part 1) on the length measurements and lesion scores of the claws were used to reveal possible relationships. The Young’s modulus values were significantly higher (p < 0.001 or p < 0.01 depending on location of claw) in the sows of farm C compared to those in sows of farms A and B and in sows of farm B compared to those in the sows of farm A. Yield and maximum stress values were significantly higher (p < 0.05 or p < 0.001 depending on the location of the claw) in the sows of farm C compared to those in the sows of farm A and in the sows of farm B compared to those in the sows of farm A. An increase in heel-sole length decreased all mechanical indices. Young’s modulus and yield stress were associated with wall lesion severity while maximum stress with wall and heel lesion severity. Overall, we conclude that mechanical efficiency deteriorates as length and lesion score increases.

Elastic Strain Energy of a Nanowire in Three-Point Bending Test with the Consideration of Surface Effects

2011 ◽  
Vol 268-270 ◽  
pp. 67-71
Author(s):  
Xian Wei Zeng ◽  
Jia Quan Deng
Keyword(s):  
Young’S Modulus ◽  
Elastic Strain ◽  
Strain Energy ◽  
Young's Modulus ◽  
Elastic Strain Energy ◽  
Theoretical Models ◽  
Bending Test ◽  
Three Point Bending ◽  
Force Microscopy ◽  
Atomic Force

Three-point bending tests of nanowires with Contact atomic force microscopy reveal that the Young’s modulus of a nanowire is size-dependent. The modulus changes with the diameter of a nanowire. This size dependency can be explained within the framework of classical continuum mechanics by including the effects of surface stress. In this study, an analytical solution has been derived for the elastic strain energy of a nanowire with both ends clamped and contacted by an AFM tip at its midpoint. Different from previous theoretical models, the present model can handle the case of large deflection, where the displacement of the nanowire is in the same order of the diameter. Based on the equivalence of elastic strain energy, the apparent Young’s modulus of a nanowire is expressed as a function of the elastic modulus of the bulk and that of the surface, and the dimensions of a nanowire.

scholarly journals Estimating Young’s Modulus of Materials by a New Three-Point Bending Method

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Xiaohu Zeng ◽  
Shifeng Wen ◽  
Mingxi Li ◽  
Gongnan Xie
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Test Method ◽  
Bending Test ◽  
Contact Friction ◽  
Specimen Preparation ◽  
Test Accuracy ◽  
Theoretical Derivation ◽  
Three Point Bending ◽  
Aluminum Alloy 2024

A new test method based on the three-point bending test is put forward to measure Young’s modulus of materials. The simplified mechanical model is established to make theoretical derivation. This method has not only the advantages of simple specimen preparation and convenient loading device, but also higher precision than the traditional three-point bending method. The method is adopted to obtain Young’s modulus of the aluminum alloy 2024. The feasibility of the method has been demonstrated by comparisons with the corresponding results obtained from the finite element method and experiment method. And the influence of contact friction on the test accuracy is analyzed.

Dynamic Properties of Wood-Plastic Composites

2011 ◽  
Vol 101-102 ◽  
pp. 1078-1081
Author(s):  
Gui Wen Yu ◽  
Shuang Lan ◽  
Jian Yuan Feng ◽  
Zhuang Liu
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Dynamic Properties ◽  
Bending Test ◽  
Wood Plastic Composites ◽  
Three Point Bending ◽  
Dynamic Young’S Modulus ◽  
Bending Modulus ◽  
Plastic Composites ◽  
Dynamic Young's Modulus

Wood-plastic composites (WPC) , which were made of virgin high-density polyethylene (HDPE) with poplar fibers as filler, were measured by three vibration nondestructive testing (NDT) methods. The values of dynamic Young’s modulus of specimens were measured by different vibration NDT methods, and the values of static bending modulus of elasticity (MOE) were also determined by three point bending test according to ASTM D790-03. The paper analyzed the variability of the dynamic young’s modulus of WPC based on virgin HDPE obtained with different NDT methods, and the correlativity was also estimated between the dynamic Young’s modulus and the static MOE of WPC based on virgin HDPE. These results suggest that WPC can be made of virgin HDPE, and the NDT methods are appropriate to estimate the dynamic Young’s modulus of WPC based on virgin HDPE.

Nondestructive Testing of Wood-Plastics Structural Plates with Stiffener

2011 ◽  
Vol 314-316 ◽  
pp. 2087-2090
Author(s):  
Gui Wen Yu
Keyword(s):  
Nondestructive Testing ◽  
Young’S Modulus ◽  
High Density Polyethylene ◽  
Young's Modulus ◽  
Bending Test ◽  
Three Point Bending ◽  
Dynamic Young’S Modulus ◽  
Bending Modulus ◽  
Dynamic Young's Modulus ◽  
Set Up

In order to set up a new effective method for measuring mechanical properties of the wood-plastics structural plates with stiffener, three different nondestructive testing (NDT) methods were used on the specimens with stiffener, which were made of virgin high-density polyethylene (HDPE) with poplar fibers as filler. The values of dynamic Young’s modulus of the specimens were measured by a FFT system. And the values of static bending modulus of elasticity (MOE) were also determined by three point bending test according to ASTM D790-03. The paper analyzed the variability of the dynamic Young’s modulus of specimens with stiffener obtained with different NDT methods, and the correlativity was also estimated between the dynamic Young’s modulus and the static MOE of all specimens. The results suggested that the intensity of the wood-plastics structural plates could be enhanced by stiffener, and the NDT methods could be appropriate to estimate the dynamic Young’s modulus of the wood-plastics structural plates with stiffener.

Evaluation of Young’s modulus of RE123 bulk superconductors by three point bending tests

2006 ◽  
Vol 445-448 ◽  
pp. 422-426 ◽  
Author(s):  
T. Sato ◽  
K. Katagiri ◽  
T. Hokari ◽  
Y. Hatakeyama ◽  
A. Murakami ◽  
...  
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Bending Tests ◽  
Three Point Bending ◽  
Bulk Superconductors

scholarly journals Evaluating Mechanical Properties of Thin Layers using Nanoindentation and Finite-Element Modeling: Implanted Metals and Deposited Layers

1996 ◽  
Vol 438 ◽  
Author(s):  
J. A. Knapp ◽  
D. M. Follstaedt ◽  
J. C. Barbour ◽  
S. M. Myers ◽  
J. W. Ager ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Finite Element ◽  
Finite Element Modeling ◽  
Yield Stress ◽  
Young’S Modulus ◽  
Layer Thickness ◽  
Young's Modulus ◽  
Thin Layers ◽  
Element Modeling ◽  
Surface Modified

AbstractWe present a methodology based on finite-element modeling of nanoindentation data to extract reliable and accurate mechanical properties from thin, hard films and surface-modified layers on softer substrates. The method deduces the yield stress, Young's modulus, and hardness from indentations as deep as 50% of the layer thickness.

Effects of cross-sessional area and aspect ratio coupled with orientation on mechanical properties and deformation behavior of Cu nanowires

2021 ◽  
Author(s):  
Hui Cao ◽  
Wenke Chen ◽  
Zhiyuan Rui ◽  
Changfeng Yan
Keyword(s):  
Mechanical Properties ◽  
Aspect Ratio ◽  
Yield Stress ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Cu Nanowires ◽  
The Cross

Abstract Metal nanomaterials exhibit excellent mechanical properties compared with corresponding bulk materials and have potential applications in various areas. Despite a number of studies of the size effect on Cu nanowires mechanical properties with square cross-sectional, investigations of them in rectangular cross-sectional with various sizes at constant volume are rare, and lack of multifactor coupling effect on mechanical properties and quantitative investigation. In this work, the dependence of mechanical properties and deformation mechanisms of Cu nanowires/nanoplates under tension on cross-sessional area, aspect ratio of cross-sectional coupled with orientation were investigated using molecular dynamics simulations and the semi-empirical expressions related to mechanical properties were proposed. The simulation results show that the Young’s modulus and the yield stress sharply increase with the aspect ratio except for the <110>{110}{001} Cu nanowires/nanoplates at the same cross-sectional area. And the Young’s modulus increases while the yield stress decreases with the cross-sectional area of Cu nanowires. However, both of them increase with the cross-sectional area of Cu nanoplates. Besides, the Young’s modulus increases with the cross-sectional area at all the orientations. The yield stress shows a mildly downward trend except for the <111> Cu nanowires with increased cross-sectional area. For the Cu nanowires with a small cross-sectional area, the surface force increases with the aspect ratio. In contrast, it decreases with the aspect ratio increase at a large cross-sectional area. At the cross-sectional area of 13.068 nm2, the surface force decreases with the aspect ratio of the <110> Cu nanowires while it increases at other orientations. The surface force is a linearly decreasing function of the cross-sectional area at different orientations. Quantitative studies show that Young’s modulus and yield stress to the aspect ratio of the Cu nanowires satisfy exponent relationship. In addition, the main deformation mechanism of Cu nanowires is the nucleation and propagation of partial dislocations while it is the twinning-dominated reorientation for Cu nanoplates.

Sign in / Sign up

Export Citation Format

Share Document