Experimental-Numerical Approach for Characterization of Mechanical Properties of Thin Electrochemically Deposited Chromium and Copper Films

2010 ◽  
Vol 159 ◽  
pp. 157-162
Author(s):  
Sabina Cherneva ◽  
Milko Yordanov ◽  
Dimitar Stoychev ◽  
Rumen Iankov

A hybrid experimental-numerical approach, which combines microindentation experiments (where we measure the diagonal of the residual imprint after unloading) and numerical simulations by means of the finite-element method has been developed. The investigated materials in the present work are electrochemically deposited on brass substrates chromium and copper films with known thickness and unknown mechanical properties. Mechanical properties of the brass (CuZn36) substrate are known. Vickers’ microindentation experiments were carried out on the films and as a result the experimental load-displacement curves were obtained. After that the process of microindentation was modelled numerically by means of the finite-element method. Numerically obtained load-displacement curves were compared with the experimental curves. The results show good coincidence between numerical and experimental curves. Additionally it was realized nanoindentation experiment of thin copper film and these two methods (nanoindentation experiment and hybrid experimental-numerical method which combines experiment of microindentation and numerical simulations) for determination of mechanival properties of thin copper films were compared. Results obtained by means of the afore-mentioned two methods almost coincide but the second method is cheaper and gives more information about material properties of the film than the first method. It is shown that the second method is preferable to determine the mechanical properties of thin metal films.

2020 ◽  
Vol 238 ◽  
pp. 06006
Author(s):  
Tim Käseberg ◽  
Jana Grundmann ◽  
Johannes Dickmann ◽  
Stefanie Kroker ◽  
Bernd Bodermann

We designed, realized, and characterised an imaging Mueller matrix ellipsometry setup for the pixelwise measurement of the Mueller matrices in microscope images. Our setup is capable of performing measurements in reflection as well as in transmission in a broad range of angles of incidence for wavelengths between 400 nm and 700 nm. We compared measurements of specially designed nanostructured samples with AFM and SEM measurements as well as with numerical simulations using the finite element method.


Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4842
Author(s):  
Huanping Yang ◽  
Wei Zhuang ◽  
Wenbin Yan ◽  
Yaomian Wang

The nanoindentation loading response of elastoplastic materials was simulated by the finite element method (FEM). The influence of the Young’s modulus E, yield stress σy, strain hardening exponent n and Poisson’s ratio ν on the loading response was investigated. Based on an equivalent model, an equation with physical meaning was proposed to quantitatively describe the influence. The calculations agree well with the FEM simulations and experimental results in literature. Comparisons with the predictions using equations in the literature also show the reliability of the proposed equation. The investigations show that the loading curvature C increases with increasing E, σy, n and ν. The increase rates of C with E, σy, n and ν are different for their different influences on the flow stress after yielding. It is also found that the influence of one of the four mechanical parameters on C can be affected by the other mechanical parameters.


Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4090 ◽  
Author(s):  
Leszek Czechowski ◽  
Zbigniew Kołakowski

A study of the pre- and post-buckling state of square plates built from functionally graded materials (FGMs) and pure ceramics is presented. In contrast to the theoretical approach, the structure under consideration contains a finite number of layers with a step-variable change in mechanical properties across the thickness. An influence of ceramics content on a wall and a number of finite layers of the step-variable FGM on the buckling and post-critical state was scrutinized. The problem was solved using the finite element method and the asymptotic nonlinear Koiter’s theory. The investigations were conducted for several boundary conditions and material distributions to assess the behavior of the plate and to compare critical forces and post-critical equilibrium paths.


Forests ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 525 ◽  
Author(s):  
Nadežda Langová ◽  
Roman Réh ◽  
Rastislav Igaz ◽  
Ľuboš Krišťák ◽  
Miloš Hitka ◽  
...  

The research on population shows that the count of overweight people has been constantly growing. Therefore, designing and modifying utility items, e.g., furniture should be brought into focus. Indeed, furniture function and safety is associated with the weight of a user. Current processes and standards dealing with the design of seating furniture do not meet the requirements of overweight users. The research is aimed at designing flexible chairs consisting of lamellae using the finite element method (FEM). Three types of glued lamellae based on wood with different number of layers and thickness were made and subsequently, their mechanical properties were tested. Values for modulus of elasticity and modulus of rupture were used to determine stress and deformation applying the FEM method for modelling flexible chairs. In this research, the methodology for evaluating the ultimate state of flexible chairs used to analyse deformation and stability was defined. The analysis confirms that several designed constructions meet the requirements of actual standards (valid for the weight of a user up to 110 kg) but fail to meet the requirements for weight gain of a population.


Author(s):  
Belghoul Hakima ◽  
Madani Kouider ◽  
Merdaci Slimane ◽  
Rezgani Laid

This work consists of the study is to analysis by the finite element method the effect of the ageing of the adhesive exposed simultaneously to the temperature and water on the degradation of its mechanical properties and consequently on the transfer of loads from the plate to patch. The stress intensity factor was evaluated according to immersion time and temperature. Several parameters have been taken into consideration, namely the properties of the composite patch, temperature, water absorption, rate and length of crack, the distribution of maximum shear stresses in the adhesive and peel in the patch were also analyzed.


2017 ◽  
Vol 899 ◽  
pp. 272-277
Author(s):  
Hugo Dutra Gomes ◽  
Maria Carolina dos Santos Freitas ◽  
Luciano Pessanha Moreira ◽  
Flavia de Paula Vitoretti ◽  
Jose Adilson de Castro

The present study is primarily engaged in the implementation of the incremental stamping process in a computerized numeric control This paper presents two different approaches to this forming process, an experimental and other numerical. Experimental used by the computer numerical control to perform the printing process and performs numerical simulations of the process using the finite element method. Some parameters are analyzed in both approaches, such as product geometry effects, tool geometry, tool speed, tool path, contact conditions and mechanical properties of the materials.


2019 ◽  
Vol 109 ◽  
pp. 00093 ◽  
Author(s):  
Olena Slashchova ◽  
Ihor Slashchov ◽  
Iryna Sapunova

The article is devoted to development of methods for geofiltration calculations with taking into account peculiarities of changes of the rock physical and mechanical properties at water saturation. Methods: mathematical modeling of geomechanical and filtration processes with the help of finite element method and laboratory and underground studies. A mathematical model was formulated for solving a problem of elasticity theory by the finite element method, which took into account peculiarities of water-saturated rocks. Pattern of stress-strain state changing in the fractured water-saturated rocks under the action of critical loads, which occurred around the preparatory roadways during their operation, were established. In order to solve the filtration problems, a bank of collected initial data on physical and mechanical properties of water-saturated rocks was processed with the help of variation coefficients, which were taken into account by the method, which assumed calculation of the model loading with critical parameters.


Sign in / Sign up

Export Citation Format

Share Document