Estimation of FeB layer’s yield strength by comparison of finite element modeling with experimental data

2009 ◽  
Vol 40 (11) ◽  
pp. 1140-1147 ◽  
Author(s):  
O. Culha ◽  
M. Toparli ◽  
T. Aksoy
2004 ◽  
Vol 19 (1) ◽  
pp. 315-324 ◽  
Author(s):  
R. Schwaiger ◽  
O. Kraft

A comprehensive study was undertaken to identify the extent to which the mechanical properties of thin metal films on substrates could be determined quantitatively from instrumented sharp indentation. The mechanical behavior of thin Cu films on substrates was investigated using three different methods: nanoindentation, cantilever microbeam deflection, and microtensile testing. Finite element calculations of the nanoindentation and microbeam deflection experiments were conducted to extract yield strength and hardening modulus. Systematic experiments were performed to investigate the consistency of the different experimental techniques. The mechanical behavior of the Cu films was observed to depend on the film thickness. However, the results from finite element modeling of nanoindentation and microbeam deflection are quite different. In both cases, unique solutions for yield strength and hardening modulus were found. This is particularly noteworthy for the nanoindentation experiments; it is argued that the substrate destroys the self-similarity that is present during indentation of bulk material using a Berkovich tip. Microbeam deflection experiments seem to be more sensitive to the elastic–plastic transition, whereas the nanoindentation results describe the mechanical behavior at larger plastic strains. This is corroborated by microtensile tests.


Author(s):  
Levi J. Suryan ◽  
Atanas A. Atanasov ◽  
Mitchell A. Daniels ◽  
John P. Parmigiani

The ever increasing use of composite materials in today’s society has created a drastic demand for better modeling of their behavior. The difficulty arises in that many modern composite structures are unique in shape and are exposed to a variety of loading situations. More specifically, loading scenarios which cause out-of-plane shear (Mode III) or mixed mode (Mode I + Mode II + Mode III) failure are of greatest challenge to model. This study investigates the capabilities of Simulation Composite Analysis (SCA), a composites software by Autodesk, in modeling failure in notched carbon-fiber composite panels loaded in Mode III. SCA was used with the finite element modeling software Abaqus/Standard (Dassault Systèmes) to model six different laminate stacking sequences. Three of the layups featured 40 plies through the thickness and the other three had 20 plies, with each containing either 10, 30, or 50 percent zero degree plies. The modeled panels were displaced as to create for a Mode III loading condition and the resulting maximum loads, load-displacement plots, and damage propagation outputs were compared to experimental results. It was found that SCA can determine the maximum failure load of the panels with an average of 11.6 percent deviation from experimental values. For one laminate stacking sequence in particular, the software determined maximum loads that deviated less than 1 percent from the experimental data. The load-displacement plots showed good correlations with experimental data in the linear region; however, the load-displacement behavior after damage was well modeled for only certain layups. The damage propagation paths for all the panel models were similar to the experimental panels in general, though self-similar damage propagation was not captured by the FEA models. Overall, Mode III failure in the notched carbon fiber panels was satisfactorily modeled for maximum load, but continued development is needed for predicting damage propagation paths. Modeling Mode III failure in composites is a difficult task; therefore, determining accurate methods in which to model such failure will be a substantial benefit to the composites engineering community. If low cost computer models can be established which accurately capture material damage and failure, the need for expensive and time-intensive experiments may be greatly reduced.


Author(s):  
T. J. Moffat ◽  
W. L. Cleghorn

Finite element modeling of bird impacts has been developed and calibrated using the 3-D impact analysis code MSC/DYTRAN. These modeling efforts have shown that the Arbitrary Lagrange Euler (ALE) formulation within MSC/DYTRAN is capable of capturing the physics of the bird impact problem, producing impact pressures and damage similar to that of a real bird. This work is divided into two areas. First, a review of the literature was carried out to identify the physical processes, pressures and damage associated with real bird impacts. Second, finite element modeling of two simple bird impacts cases were carried out using MSC/DYTRAN. A comparison of the finite element predictions with the experimental data showed excellent agreement, and demonstrated the robustness of the ALE formulation.


1995 ◽  
Vol 117 (3) ◽  
pp. 279-285 ◽  
Author(s):  
K. K. Mendis ◽  
R. L. Stalnaker ◽  
S. H. Advani

Finite element modeling of the finite deformation response of soft tissues presents a formidable challenge. This paper discusses the use of a large strain constitutive relationship suitable for modeling brain tissue as well as other soft biological tissue. Available experimental data on the finite deformation response of brain tissue is used to characterize the constitutive properties. Analytical modeling and finite element simulations of the experiment are performed using the proposed constitutive formulation. The numerical results compare favorably with the experimental data.


1991 ◽  
Vol 3 (1) ◽  
pp. 235-253 ◽  
Author(s):  
L. D. Philipp ◽  
Q. H. Nguyen ◽  
D. D. Derkacht ◽  
D. J. Lynch ◽  
A. Mahmood

Sign in / Sign up

Export Citation Format

Share Document