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1

Analysis of the effect of projectile impact angle on the puncture of a steel plate using the finite element method in abaqus software

Rosłaniec Kuba

Applied Computer Science

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2022

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Vol. 18, no 1

56--69

EN

This paper deals with the punctureability of a steel plate by a projectile at different angles of attack. The effect of the projectile angle on the force required to penetrate a plate made of A36 steel is presented using Finite Element Method calculation software. Using Abaqus software, a dynamic model of a projectile striking a plate was modelled and the force required to penetrate a 5 mm thick steel plate was presented. The intro-duction gives an overview of the genesis of the topic and a brief historical background. The chapter on numerical analysis presents the numerical model used and how the simulation was modelled. In the conclusions, a summary of the results was formulated and conclusions were drawn regarding the observations and insights of the analysis. The force required to penetrate the plate was observed to increase with increasing projectile angle of attack and it was found that, as the angle of the plate increased, the force required to penetrate increased.

2

Fracture limit analysis of DP590 steel using single point incremental forming: experimental approach, theoretical modeling and microstructural evolution

Pandre Sandeep, Morchhale Ayush, Mahalle Gauri, Kotkunde Nitin, Suresh Kurra, Singh Swadesh Kumar

Archives of Civil and Mechanical Engineering

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2021

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Vol. 21, no. 3

138--157

EN

The single point incremental forming (SPIF) process is gaining special attention in the aerospace, biomedical and manufacturing industries for making intricate asymmetric components. In the present study, SPIF process has been performed for forming varied wall angle conical and pyramidal frustums using DP590 steel. Initially, the conventional stretch forming process has been performed for finding the fracture forming limit diagram (FFLD). Further, it has been validated with the limiting strains found using SPIF process. The conical and pyramidal frustums deformed near to the plane strain and biaxial region, respectively. The theoretical FFLD has been predicted using seven different ductile damage models. The effect of sheet anisotropy while predicting the fracture strains has been included using Hill 1948 and Barlat 1989 yielding functions. Among the used damage models, the Bao-Wierzbicki (BW) model along with Barlat 1989 yield criterion displayed the least error of 2.92% while predicting the fracture locus. The stress triaxiality in the different forming region has been thoroughly investigated and it has been found that the higher triaxiality value reveals high rate of accumulated damage which lead to early failure of the material in the respective region. The stress triaxiality and effective fracture strains have also been found to be significantly affected by the anisotropy. The micro-textural studies have also been performed and it has been found that the increase in local misorientations and shift in the textural components from γ-fiber to ε-fiber in the corner region of the frustums worked towards limiting the formability of material and ultimately leading towards the fracture of frustums.

3

Investigation on the constraint effect on the fracture toughness assessment of stainless steel AISI 304L thin sheets

Bensaada Rachid, Almansba Madjid, Ferhoum Rabah, Sidhoum Zehra, Habak Malek

Journal of Theoretical and Applied Mechanics

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2020

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Vol. 58 nr 1

143--153

EN

The aim of the study is to assess the constraint effect induced by variation of geometric pa- rameters on fracture toughness of stainless steel 304L thin sheets. A combined experimental-computational method is used. Compact Tension (CT) tests are firstly done using a spe- cial device realized to avoid buckling problems. Finite element analysis is used including the GTN (Gurson-Tvergaard-Needleman) model based on micromechanical assumptions of ductile fracture to obtain crack propagation. The fracture toughness is evaluated using an in- cremental formulation of the J-Integral. The results obtained show a quantified dependency of the critical fracture toughness on the constraint effect.

4

Modelowanie sprzężenia pomiędzy rozwojem uszkodzeń i przemianą fazową w stali austenitycznej w warunkach temperatur kriogenicznych

Egner H., Ryś M.

Czasopismo Techniczne. Mechanika

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2012

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R. 109, z. 8-M

27--44

PL

Stale austenityczne w ekstremalnie niskich temperaturach podlegają trzem zjawiskom dyssypatywnym: plastycznemu płynięciu, przemianie fazowej γ→α' oraz rozwojowi uszkodzeń. Przeprowadzone eksperymenty dowodzą, że pojawiające się inkluzje martenzytu powodują spowolnienie rozwoju uszkodzeń plastycznych w matrycy austenitycznej. W pracy przedstawiony został opis konstytutywny zachowania się stali austenitycznej, poddanej obciążeniu w temperaturze bliskiej zeru absolutnemu z uwzględnieniem sprzężenia pomiędzy zjawiskami dyssypatywnymi. Został także przedstawiony algorytm numeryczny, opracowany w celu wykonania symulacji jednoosiowego rozciągania.

EN

FCC metals and alloys undergo at low temperatures three distinct phenomena: dynamic strain ageing, plastic strain induced transformation from the parent phase (γ) to the secondary phase (α') and evolution of micro-damage. Experimental results indicate the correlation between decreasing damage rate and increasing martensite content. In the present paper the constitutive model of the behaviour of stainless steel applied at cryogenic temperature was described, where the three dissipative phenomena coexist. Also the numerical algorithm was worked out, and numerical simulation of uniaxial tension was performed.

5

Elastic, perfectly plastic hollow sphere problem: a finite strain solution and energetic analysis

Zambelli S., Hild F., Trumel H., Roy G., Pellegrini Y. -P.

Foundations of Civil and Environmental Engineering

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2010

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No. 13

117--127

EN

The growth of a void in a sphere of an elastic perfectly plastic material subjected to an external hydrostatic loading is modeled in the framework of irrotational finite strains. It is shown that, for small initial void volume fractions, the infinitesimal plastic strain hypothesis leads to a gross overestimation of the void growth kinetics. This assumption is relaxed in the present work, and the analytical results compare exactly with numerical simulations carried out with the commercial finite element code ABAQUS. A thermodynamic analysis is then performed, and will be considered as a basis for investigating thermal softening and micro-inertia effects on the damage process.

6

On micro-damage in hot metal working. P. 2 Constitutive modelling

Lin J., Foster A. D., Liu Y., Farrugia D. C., Dean T. A.

Engineering Transactions

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2007

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Vol. 55, iss. 1

43-60

EN

Damage constitutive equations are formulated to model the evolution of grain boundary and plasticity-induced damage for free-cutting steels under hot forming conditions. During high temperature, high strain rate deformation, material degradation has characteristics of both creep damage at grain boundaries, and ductile damage surrounding hard inclusions. This has been experimentally observed and is reported in the companion paper. This paper describes the development of unified viscoplastic-damage constitutive equations, in which the nucleation and growth of both damage types are considered independently. The effects of deformation rate, temperature, and material microstructure on damage evolution are modelled. The proposed damage evolution equations are combined with a viscoplastic constitutive equation set, enabling the evolution of dislocation hardening, recovery, recrystallisation, grain size, and damage to be modelled. This set of unified, mechanism-based, viscoplastic damage constitutive equations is determined from experimental data of a freemachining steel for the temperature range 1173- 1373 K. The fitted model is then used to predict damage and failure features of the same material tested using a set of interrupted constant strain rate tests. Close agreement between the predicted and experimental results is obtained for all the cases studied.

7

Survey of modern trends in analysis of continuum damage mechanics

Ambroziak A., Kłosowski P.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2006

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Vol. 10, No 4

437-454

EN

A brief review of the damage mechanics literature is given. As this area of scientific research is very modern, the authors have restricted themselves to about 100 most impor-tant books and papers. Basic equations to introduce the isotropic model in the framework of thermodynamics are given in a form easily applicable in numerical symulations.