Peridynamic Simulation to Fracture Mechanism of CBN Grain in the Honing Wheel Dressing Process

Regularly dressing of CBN honing wheel is an effective way to keep its sharpness and correct geometry during honing process. This study aims to understand the fracture mechanism of single CBN grain in the dressing process of honing wheel. The honing wheel dressing process was simplified into the dressing process of grinding wheel, and the bond-based Peridynamic method considering bond rotation effect was developed to investigate the progressive fracture evolution, stress characteristics, and fracture modes of CBN grains in this process. It was found that fracture evolution of CBN grains mainly underwent four stages: elastic deformation, damage initiation, crack formation, and macro fracture. In addition, the fracture initiation and propagation were mainly determined by the tensile and shear stress, where the former led to mode I fractures and the latter led to mode II fractures. The propagation of mode I fractures was stable while the propagation of mode II fracture was unstable. The results show that the Peridynamic approach has great potential to predict the fracture mechanism of CBN grain in the dressing process of honing and grinding wheels.

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A Dislocation Migration Approach to Mode II Fracture Initiation and Propagation under Cyclic Loading

10.1063/1.3452145 ◽

2010 ◽

Author(s):

A. Karami ◽

J. Szymanski ◽

Jane W. Z. Lu ◽

Andrew Y. T. Leung ◽

Vai Pan Iu ◽

...

Keyword(s):

Cyclic Loading ◽

Fracture Initiation ◽

Mode Ii ◽

Mode Ii Fracture ◽

Initiation And Propagation

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Effect of Prestrain at Elevated Temperature on the Fracture Behavior of High Strength Steels

Journal of Engineering Materials and Technology ◽

10.1115/1.3225612 ◽

1983 ◽

Vol 105 (1) ◽

pp. 16-20 ◽

Cited By ~ 1

Author(s):

K. Satoh ◽

M. Toyoda ◽

Y. Mutoh

Keyword(s):

Elevated Temperature ◽

Cleavage Fracture ◽

Fracture Mechanism ◽

Strain Aging ◽

Fracture Behavior ◽

Present Report ◽

High Strength Steels ◽

High Strength ◽

Fracture Initiation ◽

Initiation And Propagation

It is well known that fracture initiation behavior is influenced by weld thermal straining. In the present report, attention is focused on the influence of weld thermal straining on the fracture mechanism. The influence of prestrain at elevated temperature or strain-aging on the initiation and propagation behaviors of ductile and cleavage fracture in KD32 and HT80 steels is investigated. A relationship between the increase in the lowest temperature at which a tear dimple region can be observed (Ti) or the decrease in stretched zone width and the increase in hardness at the notch tip is found.

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The Effects of In-Service Induced Reduction of Bonding Quality on the Mode I, II, and I-II Fracture Toughness of CNT Nanocomposites

Volume 1: Advances in Aerospace Technology ◽

10.1115/imece2016-66907 ◽

2016 ◽

Cited By ~ 1

Author(s):

Masoud Yekani Fard ◽

Brian Raji ◽

John M. Woodward ◽

Aditi Chattopadhyay

Keyword(s):

Fracture Toughness ◽

Energy Release Rate ◽

Energy Release ◽

Release Rate ◽

Accelerated Aging ◽

Beam Theory ◽

Mode I ◽

Mode Ii ◽

Initiation And Propagation ◽

Calibration Methods

Tests were carried out to determine the interlaminar fracture toughness of stitch-bonded biaxial polymer matrix carbon nanotube nanocomposites for mode I, II, and I-II including durability effects. Analysis of the test specimens in terms of mode I energy release rates showed good agreement among Modified Beam Theory, Compliance Calibration, and Modified Compliance Calibration methods. End-Notched Flexure (ENF) and four point End-Notched Flexure (4ENF) tests gave very consistent crack initiation and propagation results for mode II fracture. The results show that the critical mode I energy release rate for delamination decreases monotonically with increasing mode II loading. The effects of accelerated aging (60°C and 90% Rh) on fracture properties were studied. Early accelerated aging (0–12 months) has the dominant diminishing effect on energy release rate initiation and propagation in composites and nanocomposites.

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Simulation and validation of disbond growth in co-cured composite skin–stringer specimens using cohesive elements

Journal of Composite Materials ◽

10.1177/0021998317715505 ◽

2017 ◽

Vol 52 (6) ◽

pp. 807-822 ◽

Cited By ~ 4

Author(s):

S Nadeem Masood ◽

SR Viswamurthy ◽

Arun Kumar Singh ◽

M Muthukumar ◽

Kotresh M Gaddikeri

Keyword(s):

Numerical Simulations ◽

Numerical Models ◽

Plane Deformation ◽

Computation Time ◽

Interface Fracture ◽

Mode I ◽

Mode Ii ◽

Cohesive Element ◽

Cohesive Elements ◽

Damage Initiation

Separation of skin and stringer is likely to be a failure mode in co-cured composites stiffened panels where there is considerable out-of-plane deformation. Such deformations are possible when a stiffened skin structure is loaded in compression/shear beyond buckling or in structures which contain a disbond/delamination at the skin–stringer interface. Prediction of damage initiation and progressive growth in numerical simulations require parameters such as interface fracture toughness which have to be obtained through specimen tests. Since interface toughness is generally mode dependent, this study deals with the design and testing of three different configuration of blade stiffened co-cured composite skin–stringer specimens under mode-I and mode-II dominated loading. Finite element numerical models are developed using three-dimensional cohesive elements to predict the disbond growth under mode-I and mode-II dominated loading. The work also addresses the complexities in the convergence of numerical simulations that arise due to cohesive elements. A systematic way to obtain the best values for cohesive element parameters while finding a balance between accuracy of the results, computation time and numerical stability is presented. The present cohesive element modelling and analysis methodology successfully predicted the disbond growth in skin–stringer specimen and can be used to predict disbond/delamination onset or growth in composite stiffened structures subjected to high bending.

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Thermal Delamination Modelling and Evaluation of Aluminium–Glass Fibre-Reinforced Polymer Hybrid

Polymers ◽

10.3390/polym13040492 ◽

2021 ◽

Vol 13 (4) ◽

pp. 492

Author(s):

Zhen Pei Chow ◽

Zaini Ahmad ◽

King Jye Wong ◽

Seyed Saeid Rahimian Koloor ◽

Michal Petrů

Keyword(s):

Crack Front ◽

Cohesive Zone ◽

Experimental Tests ◽

Mode I ◽

Mode Ii ◽

Cohesive Model ◽

Reinforced Polymer ◽

Glass Fibre Reinforced Polymer ◽

Fibre Reinforced Polymer ◽

Glass Fibre Reinforced

This paper aims to propose a temperature-dependent cohesive model to predict the delamination of dissimilar metal–composite material hybrid under Mode-I and Mode-II delamination. Commercial nonlinear finite element (FE) code LS-DYNA was used to simulate the material and cohesive model of hybrid aluminium–glass fibre-reinforced polymer (GFRP) laminate. For an accurate representation of the Mode-I and Mode-II delamination between aluminium and GFRP laminates, cohesive zone modelling with bilinear traction separation law was implemented. Cohesive zone properties at different temperatures were obtained by applying trends of experimental results from double cantilever beam and end notched flexural tests. Results from experimental tests were compared with simulation results at 30, 70 and 110 °C to verify the validity of the model. Mode-I and Mode-II FE models compared to experimental tests show a good correlation of 5.73% and 7.26% discrepancy, respectively. Crack front stress distribution at 30 °C is characterised by a smooth gradual decrease in Mode-I stress from the centre to the edge of the specimen. At 70 °C, the entire crack front reaches the maximum Mode-I stress with the exception of much lower stress build-up at the specimen’s edge. On the other hand, the Mode-II stress increases progressively from the centre to the edge at 30 °C. At 70 °C, uniform low stress is built up along the crack front with the exception of significantly higher stress concentrated only at the free edge. At 110 °C, the stress distribution for both modes transforms back to the similar profile, as observed in the 30 °C case.

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