Twinned-serrated chip formation with minor shear bands in ultra-precision micro-cutting of bulk metallic glass

Previous studies have reported significant differences in the Johnson-Cook (J-C) parameters of Ti6Al4V alloy. Thus, various serrated chip morphologies, cutting forces, and cutting temperatures are obtained when different constitutive parameters are used for numerical and simulation analyses, which decreases the reliability of the simulation model. Therefore, it is necessary to investigate and analyze simulation errors due to differences in the J-C parameters. In this study, the mechanism of the serrated chip formation of Ti6Al4V is thoroughly analyzed using the uniformly proportional J-C parameters. The serrated chip sensitivity, shear band spacing, serrated segmentation frequency, chip serration intensity, temperature field, strain energy, and cutting force is obtained. This study aims to improve the accuracy and reliability of the micro-cutting simulation models, as well as a reference for the selection of J-C constitutive parameters of simulation with Ti6Al4V manufactured with different heat treatments and additive manufacturing.

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Microstructure Evolution of Ti-6Al-4V Alloy during High Speed Cutting: An Investigation Using Finite Element Simulation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.421.193 ◽

2013 ◽

Vol 421 ◽

pp. 193-200 ◽

Cited By ~ 1

Author(s):

Tao Cui ◽

Hong Wei Zhao ◽

Chuang Liu ◽

Ye Tian

Keyword(s):

Grain Size ◽

Dynamic Recrystallization ◽

Microstructure Evolution ◽

Chip Formation ◽

High Speed ◽

Shear Bands ◽

Cutting Temperature ◽

Serrated Chip ◽

High Speed Cutting ◽

Serrated Chip Formation

In this paper, a novel model combining the microstructure prediction model and a modified constitutive model of the Johnson-Cook (JC) model was developed and embedded into FEM software via the user subroutine. The chip formation and microstructure evolution in high speed cutting of Ti-6Al-4V alloy were simulated based on the presented model. The results indicated that dynamic recrystallization mainly happened in ASBs, where the grain size had a big decline. According to the variation of cutting temperature and grain size of microstructure, the mechanism of the adiabatic shear bands (ASBs) formation was investigated deeply and concluded that dynamic recrystallization was the root cause of the serrated chip formation.

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High density of shear bands in the Vitreloy bulk metallic glass subjected to high-pressure torsion

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1008/1/012031 ◽

2021 ◽

Vol 1008 ◽

pp. 012031

Author(s):

Vasily Astanin ◽

Dmitry Gunderov ◽

Zhi Qiang Ren ◽

Ruslan Valiev ◽

Jing Tao Wang

Keyword(s):

High Pressure ◽

Metallic Glass ◽

Bulk Metallic Glass ◽

High Pressure Torsion ◽

Shear Bands ◽

High Density

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Pressure-dependent flow behavior of Zr41.2Ti13.8Cu12.5Ni10Be22.5 bulk metallic glass

Journal of Materials Research ◽

10.1557/jmr.2003.0287 ◽

2003 ◽

Vol 18 (9) ◽

pp. 2039-2049 ◽

Cited By ~ 93

Author(s):

Jun Lu ◽

Guruswami Ravichandran

Keyword(s):

Metallic Glass ◽

Bulk Metallic Glass ◽

Inelastic Deformation ◽

Shear Failure ◽

Flow Behavior ◽

Shear Bands ◽

Ductile Deformation ◽

Multiaxial Compression ◽

Dependent Flow ◽

Tresca Criterion

An experimental study of the inelastic deformation of bulk metallic glass Zr41.2Ti13.8Cu12.5Ni10Be22.5 under multiaxial compression using a confining sleeve technique is presented. In contrast to the catastrophic shear failure (brittle) in uniaxial compression, the metallic glass exhibited large inelastic deformation of more than 10% under confinement, demonstrating the nature of ductile deformation under constrained conditions in spite of the long-range disordered characteristic of the material. It was found that the metallic glass followed a pressure (p) dependent Tresca criterion τ = τ0 + βp, and the coefficient of the pressure dependence β was 0.17. Multiple parallel shear bands oriented at 45° to the loading direction were observed on the surfaces of the deformed specimens and were responsible for the overall inelastic deformation.

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