Mechanical Properties of Stapedial Tendon in Human Middle Ear

2007 ◽  
Vol 129 (6) ◽  
pp. 913-918 ◽  
Author(s):  
Tao Cheng ◽  
Rong Z. Gan
Keyword(s):  
Mechanical Properties ◽  
Stress Relaxation ◽  
Middle Ear ◽  
Boundary Effect ◽  
Correlation Method ◽  
Stretch Ratio ◽  
Image Correlation ◽  
Uniaxial Tensile ◽  
Temporal Bones ◽  
Human Middle Ear

Measurement on mechanical properties of the stapedial tendon in human middle ear has not been reported in the literature. In this paper, we used the material testing system to conduct uniaxial tensile, stress relaxation, and failure tests on stapedial tendon specimens harvested from human temporal bones. The digital image correlation method was employed to assess the boundary effect on experimental data. The stress-strain relationship of the tendon obtained from experiments was analyzed using the hyperelastic Ogden model. The results presented include (1) the constitutive equation of the tendon for stretch ratio of 1–1.4 or stress range of 0–1.45MPa, (2) the mean ultimate stress and stretch ratio of the tendon at 4.04MPa and 1.65, respectively, and (3) the hysteresis and normalized stress relaxation function of the tendon. The data reported in this paper contribute to ear mechanics, especially for theoretical analysis of human ear function.

Use of Micro Tensile Test Samples in Determining the Remnant Life of Pressure Vessel Steels

2007 ◽  
Vol 7-8 ◽  
pp. 187-194 ◽  
Author(s):  
Rafal M. Molak ◽  
M. Kartal ◽  
Zbigniew Pakiela ◽  
W. Manaj ◽  
Mark Turski ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Tensile Test ◽  
Elevated Temperatures ◽  
Collaborative Study ◽  
Correlation Method ◽  
Uniaxial Stress ◽  
Operating Conditions ◽  
Image Correlation ◽  
Uniaxial Tensile ◽  
Uniaxial Tensile Test

The aim of this collaborative study was to measure mechanical properties of 14MoV67-3 steel taken from small sections of material machined in-situ from an operating high pressure collector pipe after different operating lifetimes (from 0h to 186 000h) at elevated temperatures (540°C). Conventional methods of measuring mechanical properties of materials, such as the uniaxial tensile test require relatively large test samples. This can create difficulties when the amount of material available for testing is limited. One way of measuring mechanical properties from small quantities of material is using micro tensile test samples. In this work, micro-samples with a total length of 7.22mm were used. Digital Image Correlation method (DIC) was employed for the strain measurements in a uniaxial tensile test. This paper shows that there is measurable difference in the yield, ultimate tensile strength and elongation to failure as a function of the plant operating conditions. This work demonstrates, therefore, a ‘semi-invasive’ method of determining uniaxial stress-strain behaviour from plant components.

scholarly journals Effect of PWHT on the Microstructure and Mechanical Properties of Friction Stir Welded DP780 Steel

Metals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1097
Author(s):  
Umer Masood Chaudry ◽  
Seung-Chang Han ◽  
Fathia Alkelae ◽  
Tea-Sung Jun
Keyword(s):  
Mechanical Properties ◽  
Annealing Temperature ◽  
Tensile Elongation ◽  
Image Correlation ◽  
Frictional Heat ◽  
Uniaxial Tensile ◽  
Uniaxial Tensile Test ◽  
Friction Stir ◽  
Microstructure And Mechanical Properties ◽  
Dp780 Steel

In the present study, the effect of post-weld heat treatment (PWHT) on the microstructure and mechanical properties of friction stir welded (FSW) DP780 steel sheets was investigated. FSW was carried out at a constant tool rotation speed of 400 rpm and different welding speeds (200 mm/min and 400 min/min). A defect free weld was witnessed for both of the welding conditions. The mutual effect of severe plastic deformation and frictional heat generation by pin rotation during the FSW process resulted in grain refinement due to dynamic recrystallization in the stir zone (SZ) and thermo-mechanically affected zone (TMAZ). Lower tensile elongation and higher yield and ultimate tensile strengths were recorded for welded-samples as compared to the base material (BM) DP780 steel. The joints were subsequently annealed at various temperatures at 450–650 °C for 1 h. At higher annealing temperature, the work hardening rate of joints gradually decreased and subsequently failed in the softened heat-affected zone (HAZ) during the uniaxial tensile test. Reduction in yield strength and tensile strength was found in all PWHT conditions, though improvement in elongation was achieved by annealing at 550 °C. The digital image correlation analysis showed that an inhomogeneous strain distribution occurred in the FSWed samples, and the strain was particularly highly localized in the advancing side of interface zone. The nanoindentation measurements covering the FSWed joint were consistent with an increase of the annealing temperature. The various grains size in the BM, TMAZ, and SZ is the main factor monitoring the hardness distribution in these zones and the observed discrepancies in mechanical properties.

Effect of temperature on the biaxial mechanics of excised lung parenchyma of the dog

1992 ◽  
Vol 73 (3) ◽  
pp. 1171-1180 ◽  
Author(s):  
J. C. Debes ◽  
Y. C. Fung
Keyword(s):  
Mechanical Properties ◽  
Lung Parenchyma ◽  
Tensile Tests ◽  
Stretch Ratio ◽  
Effect Of Temperature ◽  
Uniaxial Tensile ◽  
Slow Cooling ◽  
Influence Of Temperature On ◽  
Creep And Stress Relaxation ◽  
Tissue Material

The influence of temperature on the mechanical properties of excised saline-filled lung parenchyma of the dog was studied at low lung volume. The motivation of this study was to determine whether lung tissue material without the influence of surface tension undergoes a phase transition in the 20–40 degrees C range, as does synthetic elastin studied by Urry in 1984–1986. Dynamic biaxial and uniaxial tensile tests were done, and strain vs. Lagrangian stress curves were recorded during slow cooling and heating between 40 and 10 degrees C. To emphasize the effects of elastin, strains (defined as stretch ratio minus one) were kept below 30%. A slight decrease in compliance occurred with cooling over the entire temperature range. This effect may be attributed to collagen. It was accompanied by a gradual increase in length as the tissue cooled, an effect that may be attributed to elastin. This process was partially reversible with reheating. However, this effect is in contrast with the sudden drastic change in mechanical properties of synthetic elastin described by Urry. Hysteresis, creep, and stress relaxation were small at these low strains. Possible causes of these effects are discussed.

Measurement of the mechanical properties of soccer balls using digital image correlation method

2015 ◽  
Vol 12 (1) ◽  
pp. 69-76 ◽  
Author(s):  
Alireza Karimi ◽  
Reza Razaghi ◽  
Mahdi Navidbakhsh ◽  
Toshihiro Sera ◽  
Susumu Kudo
Keyword(s):  
Mechanical Properties ◽  
Digital Image Correlation ◽  
Digital Image ◽  
Correlation Method ◽  
Image Correlation ◽  
Digital Image Correlation Method

Identification of the Mechanical Properties of High-Strength Steel Using Digital Image Correlation

2014 ◽  
Vol 980 ◽  
pp. 122-126 ◽  
Author(s):  
Michaela Štamborská ◽  
Miroslav Kvíčala ◽  
Monika Losertová
Keyword(s):  
Mechanical Properties ◽  
Digital Image Correlation ◽  
Digital Image ◽  
High Strength Steel ◽  
Strain Field ◽  
High Strength ◽  
Image Correlation ◽  
Uniaxial Tensile ◽  
Large Strains ◽  
Identification Procedure

Identification of the mechanical properties of high-strength steel using digital image correlation. In this paper an experimental procedure to identify the plastic behaviour of sheet metals up to large strains using full field measurement is presented. The tests were conducted on notched specimens. This geometry generates a heterogeneous strain field which was measured during the test using a digital image correlation system. The advantage of using a heterogeneous strain field in the identification procedure is that a complex state of stress-strain can be analyzed at the same time and much more information can be obtained in a single test. On the other hand, the stress field cannot be directly computed from the test and a suitable identification procedure must be developed. Here, the virtual fields method (VFM) adapted for large strains and plasticity was used to identify the hardening behaviour and the anisotropy of the material. The values obtained with the VFM were compared with the results from a standard identification made using uniaxial tensile tests.

scholarly journals Poisson’s ratios of molded pulp materials by digital image correlation method and uniaxial tensile test

2020 ◽  
Vol 15 ◽  
pp. 155892502090827
Author(s):  
Guangjun Hua ◽  
Maoteng Yang ◽  
Weimin Fei ◽  
Fude Lu
Keyword(s):  
Poisson’S Ratio ◽  
Correlation Method ◽  
Image Correlation ◽  
Poisson's Ratio ◽  
Uniaxial Tensile ◽  
Uniaxial Tensile Test ◽  
Corrugated Board ◽  
Bamboo Pulp ◽  
Poisson's Ratios ◽  
Poisson’S Ratios

The mechanical properties of molded pulp materials are the basis of the structural optimum design of molded pulp products. Therefore, the correlations between Poisson’s ratio and fiber structure, molding process, and thickness were found for materials including wood pulp, bamboo pulp, sugarcane pulp, white mixed pulp, black mixed pulp, recycled corrugated board pulp, and recycled newspaper pulp by the uniaxial tensile test and digital image correlation method. The fiber structures of the selected molded pulp materials were investigated by scanning electron microscopy. The results revealed Poisson’s ratios of wood pulp, bamboo pulp, sugarcane pulp, white mixed pulp, black mixed pulp, recycled corrugated board pulp, and recycled newspaper pulp to be 0.169, 0.108, 0.202, 0.120, 0.166, 0.098, and 0.044, respectively. Microstructural investigation further revealed that Poisson’s ratios of molded pulp materials were related to the fiber structure and drying method. The pulp material dried outside mold under lower pressure and temperature had a smaller Poisson’s ratio, while that dried inside mold under higher pressure and temperature had a larger Poisson’s ratio. The layered phenomenon of the molded pulp materials was also found by scanning electron microscopy images: the outer layer was denser than the inner layer. These results can provide guidance for the numerical simulation analysis and optimal design of molded pulp products.

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